A probabilistic model is newly proposed for describing random deterioration of pumping wells, in consideration of application to efficient of pumping wells using a concept of asset management procedure. First,introducing a health index for quantifying specific capacity,we formulate a differential wquation describing mean deterioration of the helth index. Next, it is extended to a random differential equation, in which a Gaussian white noise is introduced for representing intensive fluctuation around the mean deterioration behavior, so that intensively random variation of the health index can be well reproduced. A probability distribution of the health index is then derived in an analytical form. Finally, the obtained probability distribution is comparred with actual data of the health index for active eight pumping wells in Joyo area, Kyoto prefecture, Japan. It is clarified that the scatter of health index of actual pumping well reproduced by the theoretically derived probability distrbution from the nrwly proposed probabilistic model.

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Shotcrete is installed in tunnels to prevent rock fall disasters. It is difficult to determine the thickness of shotcrete for each face according to the geological conditions, and it is recommended to spray 3 to 5 cm depending on the support pattern. In this study, we collected the results of quantitative evaluation of the geology of the tunnel face using image analysis technology and computer jumbo drilling data,as,well as the shotcrete thickness and rock fall information of the tunnel face, and used logistic regrssion to determine the shotcrete thickness according to the geological conditions. As a result, it was found that the shotcrete thickness can be presented with an accuracy of about 75%. We also showed that logistic regression is a machine learning method without hidden layers,so it can clearly show the relationship between geological conditions and shotcrete thickness and rock fall.

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近年 、異常な短時間集中 豪雨 の増加によって斜面災害が多く発生し、 甚大な被害を被っている 。本研究では、斜面安定工法 としてロープネットとロックボルトを併用する工法を提案しており、 この工法は 極力樹木を伐 採せずに斜面の安定化を図る。 ここでは 、ロープネットの材質 を変化させるとともに、 せん断面位置 や砂地盤 の含水比を変化させることにより、 異なった ロープネ ット 材を用いる ことによせん断抑止効果 について、 模型せん断載荷試験 を用いて検討を行った。

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NATM工法では， 岩盤評価項目を点数化して，支保パターンを決定しているが，点数化には，複数の技術者が行っている．昨今，トンネル技術者の不足に伴い ICT技術を活用した客観性の高い岩盤評価の重要性が高まっている．本研究では， NATMトンネルの切羽面の岩盤亀裂評価に深層学習の 導入 を試みた．具体的には，切羽の写真を AIに学習させて，岩盤亀裂の定量的評価について検討した．

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The determination of support patterns by field experts in NATM plays an important role in the construction of mountain tunnels. Discrepancy in judgement based on experience and bias may lead to an inconsistent evaluation method. Therefore, this research aims to realize an unbiased and standardized evaluation method by verifying the applicability of machine learning to rock evaluation. Support vector machine (SVM) is implemented to classify support patterns based on data collected from construction sites. The proposed SVM-based model shows high accuracy. Furthermore, by taking into account the current method of rock evaluation during tunnel construction, the classification accuracy further improved.

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In mountain tunnels for NATM, the rock mass rating with tunnel face is one of the most important tasks to determine the support design pattern and it is currently depended on the visual observation of experienced experts. However, the number of experts is decreasing in recent years and it is feared that it will affect tunnel construction in the future. To solve this problem, we tried to evaluate quantitatively rock fractures on tunnel face using CNN, a deep learning, with the evaluation of the 9 categories and 4 lebels of tunnel face observation style for rock fractures. In addition, we applied Grad-CAM, a visualization technique for CNN, to investigate whether CNN can actually evaluate rock fractures as a basis for decision making.

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本研究の対象地域は京都府八幡市である．八幡市は上水道水源のうち40％を地下水に依存している．今後も上水道揚水源として地下水を利用していくと考えられ，井戸枯れや地盤沈下などの地下水障害の発生が懸念される．そのため，地下水の適正利用と管理が必要となる．本研究では水源揚水井の地下水運転水位（以下運転水位とする）の将来予測手法について機械学習の適用を試みた．本研究に関連する既往の研究は，吉松らがニューラルネットワークとファジィ推論の組み合わせによって地下水位変動の予測を行い，竹本らがニューラルネットワークによる地下水位予測を行っている．これらは降雨量との関係性から浅い層の地下水位の予測を行っている．しかし，陽水量との関係を用いて深い層の地下水位の予測は行われていない．本研究では，機械学習の1種であるサポートベクター回帰（SVR)を用いて，水源揚水井地下水運転水位の将来予測モデルを構築し，その適用性について検討した．構築するにあたり，八幡市より提供された運転水位と揚水量，揚水井の諸元データを用い，3本の揚水井の将来予測モデルの構築を試みた．

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In mountain tunnels for New Austrian Tunneling Method, the rock mass rating is one of the most important factors to determine the tunnel support design pattern, but it is currently dependent on the visual inspection by experts. However, the number of experts is decreasing in recent years and it is feared that it will affect tunnel construction in the future. Therefore, in this research, we use convolutional neural network (CNN), a type of deep learning, to conduct a quantitative assessment of rock fractures in the tunnel face. Specifically, the image data of the tunnel face were divided into two parts, one for training and the other for validation. The CNN model is constructed by using image data of a tunnel face as input data and the evaluation scores for the fracture which is defined by the Ministry of Land, Infrastructure and Transport as output data, and then the model is evaluated with the validation data. The result shows that the agreement between the CNN predicted evaluation scores and the actual evaluation scores judged by experts is high and that CNN is applicable to the evaluation of rock fractures in the tunnel face.

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2018 年7 月5 日～7 日にかけて発生した西日本豪 雨災害は、斜面崩壊が頻発した。特にすべり面が 3 ｍ以内の表層崩壊は、各地で発生した。本研究では、 樹木を伐採しないロックボルト・ロープネット斜面 安定工法の敷設が行われている斜面とされていな い斜面が混在する道路斜面を対象として、土壌雨量 指数の変化とスネーク曲線の変化に基づき、本斜面 安定工法の適用性について検討した。

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道路トンネルの効率的な点検手法を考える中で，本研究では，近接目視によるひび割れ幅の測定に着目した。トンネルの覆工はコンクリートでできており，コンクリート構造物において，ひび割れ幅の現状を把握することは維持管理上極めて重要である。現在，コンクリート構造物表面のひび割れ幅の検査は，近接目視で行っている。そのため，ひび割れの点検は多大な時間と労力を必要とすることに加え，熟練した技術と経験を必要とするため，客観的かつ定量的な評価が出来ていない。そこで本研究では，近年情報分野での研究が進み，実用化例も増加しているディープラーニングを活用し，デジタル画像によるトンネル覆工のひび割れ幅の計測を行った。そしてどのようなカメラ・性能の画像でも一定の客観的かつ定量的評価を行う事ができる手法の開発を目標とした。前段として，撮影条件および撮影対象物条件を整えた場合に，未知のひび割れ覆工画像を入力した際において，正確なひび割れ幅の検出を行えるような手法の確立を試みた。

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近年，豪雨の増加により全国各地で土砂災害が発生しており，このような水に起因する災害の減災対策が研究・開発されている．しかし，流体中の岩石がどのように移動するのかを解明することは非常に困難であり，効率的な手法が未だ開発されていない．そこで，本研究では固体と流体の相互作用問題に着目し，固体部には不連続変形法(DDA)を，流体部にはメッシュフリー解析法の一つである粒子法(MPS)を用いた新たな解析手法を提案した．流体の岩塊への作用については，流体中の岩塊（DDAブロック）に領域を定義し，この領域内を水粒子が通過する際に，DDAブロックに流体力を作用させた．そして，その相互作用理解のため基本問題を解き，実現象と比較することで解析手法の有効性を示した．

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我が国は地形的，気象的条件は厳しい環境にある．さらに，近年では，豪雨の増加により全国各地，また，その他のアジア地域でも土砂災害が発生している． 土砂災害のような固体と流体の運動について従来の研究では，時間過程に依存しない静的な状態の解析や，岩石のような不連続性体だけを考えた解析が主であり，水は無条件に扱われていた．そのため，それらの解析は充分満足できるものではなかった．しかし、水は確実に岩石の安定性に影響している． そこで本研究では，固体と流体，特に，土石流におけるそれらの相互作用問題に着目し，不連続変形法であるDDAと，メッシュフリー解析法の一つである粒子法のMPSを用い，簡単な解析を試みた．土石流における流下水の岩塊への作用を表現するために，斜面を流下する土石流中の岩塊（DDAブロック）について領域を定義した．この領域内を水粒子が通過すると，DDAブロックに流体力を作用させることで，土石流における新たな解析手法の適応の可能性を示した．

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我が国の道路は，高度経済成長期に急ピッチで整備されてきた．建設された膨大な数の法面は，現在，老朽化が進んでおり，これらの法面地盤の安定性，耐久性を，効率よく把握，評価する必要がある．法面の安定性に関わる問題は，背面地山の風化や変動が大きく影響するため，物理探査を用いる方法が取られはじめている．単独の物理探査による解釈には限界があり，複数の物理探査で評価することが望まれる．しかし現在，複数の物理探査によって得られたデータの総合的な評価手法は確立されていない．そこで，本研究では弾性波探査，表面波探査，電磁探査に着目し，原位置で得られた各々のデータに自己組織化マップとk-means法を適用することで，複数の物理探査結果の複合的評価を試みた．

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In this research, we make the three-dimensional geological structure model for groundwater simulation. The model can consider the influence that pumping gives the groundwater flow in groundwater simulation. The model represents the topography of the area exactly. It was proved by comparing the topographical map with the model.

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We suggest the Rope Net and Rock Bolt method having function of slope stabilization and conservation of natural state. The purpose of study is to establish design of ropenet and rockbolt method preserving landscape and natural environment. The mechanical behavior and deformation behavior of the method were partially clarified by past studies. The purpose of this research is to understand the mechanism of reinforcement effect by rock bolt setting of the method and the result of research add in the existent design method.

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本研究は，都市における地下水有効利用の一つとして提案されている帯水層蓄熱システムについて着目した。本システムを導入する際に，地下水利用時の揚水によって起きる圧密の問題や，熱移動に関しての挙動を把握する必要がある。そこで，実際に本システムが大都市沿岸部に導入された場合を想定し，有限要素法による 3 次元浸透・圧密連成解析と，3 次元地盤熱水分移動解析を行った。その結果，本システムは圧密沈下の影響はなく，想定した地上11階，地下4階の建物では，夏季15%，冬季30%の電力消費が削減されることが判明した。

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京都市伏見区は京都市の最南部に位置し，日本酒の有名な産地である．対象地は4K㎡ほどの地域に酒造会社が所有する約50本の井戸が密集し，地下水の利用が盛んな地域である．本研究は，京都市伏見地域における浅井戸観測井の水位を対象として，周辺の揚水を伴った地下水位挙動を明らかにするために，現場計測ならびに数値解析による検討を行ったものである．本研究の成果として，浅井戸観測井の水位変化を求めるための3次元地層モデルを作成し，酒造会社が密集する場においての地下水位を推定し，実測値と比較的に整合していることが認められた．

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研究対象地は4k㎡ほどの地域に約50本の揚水井が密集し、水質が非常に良く地下水の利用が盛んな地域である。本研究は、対象地における周辺の揚水を伴った地下水の水位変動や地下水汚染が発生した場合を想定し、対象地に連続する粘土層の役割を現位置計測と数値解析により検討したものである。広域における観測井の水位を再現するための3次元地質モデルを作成し、浸透流解析を行った結果は実測値と比較的整合した。そこで、広域的なモデルにより得た水頭値を境界条件とした局所的なモデルを作成し再度浸透流解析を行った結果、詳細な地下水流動を推定することができた。それらの結果を基にした移流分散解析を行い、最も汚染が広がりやすい汚染物質の挙動に対する粘土層の役割を定量的な検討結果を基に検証した。

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近年では，老朽化法面の健全度を評価するために，様々な物理探査が着目されている．しかし、単独の物理探査による物理的情報では地山状態を解釈するのに限 界があり，複数の物理探査を用いて評価をすることが望ましい．そこで本研究では，自己組織化マップ（Self-Organizing Maps：SOM）とk-means法を用いることで複数の物理探査データ（P波速度，S波速度，比抵抗）を分類し，地盤内の性状を推定した．また，定期 的に計測されるデータから経時変化のモニタリングを試みた。分類結果は，ボーリング調査による地盤情報と整合性が高いことから，本手法は老朽化法面の岩盤 性状を把握するために有効であることが示された．

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上水道の水源として地下水を利用している割合が高い京都府城陽市及び八幡市の浄水場を対象とし，複数の揚水井が及ぼす地下水性状への影響について検討し た．初めに広域的な範囲における揚水シミュレーション解析を行い，複数の自治体における相互の影響を検討した．さらに，広域モデルでの結果を基に，より詳 細に地形や地質構造を考慮した局所モデルを作成した．そして，解析結果及び経年的な地下水位変動の計測データを基に，揚水が地下水位変動に及ぼす影響につ いて検討を行った．また，井戸の老朽化と考えられる水位変動を数値解析により再現することを試みた．その結果，今回構築した解析モデルを用いて，精度よく 複数の揚水井での水位変動を再現することができた．

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In Japan, many of the slopes covered with shotcrete have aged considerably. Therefore, there is a risk that slope failures may occur due to the effects of factors such as seasonal weather patterns, natural disasters, climate change, heavy rainfall, and earthquakes. Therefore, it is important to develop a method for monitoring the stability and the durability of these slopes. In this paper, we propose a technique (hereafter referred to as “conversion analysis”) that converts seismic velocity and electric resistivity data to porosity and saturation, which is then used to monitor weathering and groundwater fluctuation behind the slope. There have been several studies regarding the empirical relations between geophysical parameters such as seismic velocity and resistivity, and engineering properties such as porosity and saturation. At the investigation sites, seismic tomography and resistivity tomography were carried out between the ground surface and the boreholes. Investigation was conducted a total of 5 times, once in the summer and once in the winter for 3 years. As the results, it was possible to monitor the signs of seasonal variation and weathering in the ground.

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近年では，老朽化法面の健全度を評価するために，様々な物理探査が着目されている．単独の物理探査による物理的情報では地山状態を解釈するのに限界があり，複数の物理探査を用いて評価をすることが望ましい．そこで本研究では，自己組織化マップ（Self-Organizing Maps：SOM）とk-means法を用いることで複数の物理探査データ（P波速度，S波速度，比抵抗）を分類し，地盤内の性状を推定した．また，定期的に計測されるデータから経時変化のモニタリングを試みた．分類結果は，ボーリング調査による地盤情報と整合性が高いことから，本手法は老朽化法面の岩盤性状を把握するための複合的な評価が可能であることが示された

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トンネルは様々な地質条件の中に掘削されることから，設計に関する明確な基準の設定が困難である．そのため，地山の力学挙動を適切に再現し得る解析手法の構築が求められている．そこで本研究では，個別要素法を用いて多層地盤中における浅層トンネルの掘削シミュレーション解析を実施し，その妥当性を評価する．その際，実際のトンネル崩落事故を対象とし，対象地域の多層地盤をモデル化し，一軸圧縮試験シミュレーション解析，二軸圧縮試験シミュレーション解析によって，支保工及び地山の物性を再現し得るパラメータを決定した．掘削シミュレーション解析では，地下水やインバート支保工等の条件を設定することにより，崩落の有無について検討した．

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eople in Kyoto basin. In this research, we chiefly proceed on-site measurement and analysis to predict how the 1 p.p.m source of the contamination spreads in the shallow layer. We stress that there are no pollutants actually being produces in these areas. In order to ensure the long term usability of the regions groundwater, long-term observation and analysis will be necessary. Firstly, we measured the groundwater level and came to understand the groundwater properties in this area. Next, we analyzed the 3D simulation of groundwater while using those data. Having arranged the bore data, we then constructed an accurate stratum model necessary for analyzing. We then analyzed the seepage flow in order to reproduce the groundwater flow. Finally, we assumed how contamination occurred in groundwater by using the result of the seepage flow analysis with maximum accuracy, and subsequently carried out the advection and diffusion analysis. And, we are able to predict how the 1 p.p.m source of the contamination spreads in 5 yeas in the shallow layer. For the purpose of groundwater conservation, we would like to use this simulation model as a general assessment to protect the resource and the environment of groundwater.

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老朽化法面の健全度の調査において，複数の物理探査法を用いて総合的に評価する方法が注目されている．しかしながら，現在のところ複数の物理探査を総合的に解釈する手法は確立されておらず，技術者の専門的な知識や経験に基づく高度な判断が要求され，物理探査の解釈にばらつきが生じる可能性があるのが現状である．そこで本研究では，情報処理工学の分野で幅広く使われている自己組織化マップ(Self-Organizing Maps : SOM)1)～3)を用いて，原位置において実施された複数の物理探査の結果をクラスタリングし，総合的に解釈する手法の提案を試みた．SOMによる地盤評価事例は，岩盤斜面の危険度評価4)や，南海トラフ沈み込み帯における断層面の物性評価5)や，堤防内土質性状の分類6)の幾つかあるのみで，昨年著者らは老朽化法面の地盤性状評価への適用を試みた7)．本報告では客観的なクラスター分類行うために，k-means法8)の適用を行った．分類結果は，ボーリング調査で明らかとなった岩盤の割れ目による品質評価(Rock Quality Designation : RQD)，岩種および岩級区分と関連付けられることから，本手法は，岩盤性状を把握するための物理探査の複合評価が有効であることが示せた．

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In recent years, geophysical exploration is the remarkable method to evaluate the soundness of the aging slope. However, there is a limit of the interpretation by a geophysical exploration, so two or more geophysical explorations are used to make up for the limit of the interpretation. In this paper, we tried to evaluate the cluster classification of the ground state by two or more geophysical explorations with self-organizing maps (SOM), and compared the cluster classification with the results of the analysis to convert the combination of the seismic velocity and the resistivity into the porosity and the saturation. It was possible to evaluate the ground state of each cluster by SOM.

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In our country, it is reported that there are a lot of cases which the slope failure is caused by the rainfall. Then, the purpose of our study is to analyze slope failure simulation caused by rainfall on fill slopes by DEM. Especially we focus on the real field. And, we regarded a decrease of clod strength as a decrease of frictional coefficient on this analysis. As a result, we have been able to calculate the decreasing rates of frictional coefficient and the start speeds of three cases that had different ways of groundwater's rising. From this result, it is recognized that the decreasing rate of the Case3 was the largest, and the start speed and move distance were also large. So, when it is heavy rain, we should take note it in Case3, and we can say that the possibility of influencing the inhabited area under the slope is high at collapse.

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Kyoto city has various traditional cultures and industries. One of them is the production of Japanese sake, for which Fushimi Ward in Kyoto is famous. The purpose of our study is to maintain the groundwater resource that supports the life and culture of people in Fushimi ward. Firstly, we measured the groundwater level and came to understand the groundwater properties in this area. Next, we analyzed the 3D simulation of groundwater while using those data. Having arranged the bore data, we then constructed an accurate stratum model necessary for analyzing. We then analyzed the seepage flow in order to reproduce the groundwater flow. Finally, we assumed how contamination occurred in groundwater by using the result of the seepage flow analysis with maximum accuracy, and subsequently carried out the advection and diffusion analysis. For the purpose of groundwater conservation, we would like to use this simulation model as a general assessment to protect the resource and the environment of groundwater.

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This study concerns the protection method and the natural maintenance of aging shotcrete. In Japan, in the high economic growth period in 1960’s, a great number of slopes were formed to construct many roads and most slope protection methods were to cover shotcrete on the slope. In recent years, with concerns about the environmental and landscape, the construction of shotcrete is decreasing. However, even now about 7,000,000㎡of shotcrete is laid every year, and it is predicted that the total amount of shotcrete is enormous. Now, about 60 years passes after a great number of shotcrete was laid, and shotcrete have been aging. Therefore, we suggested the method which construct for directly aging shotcrete in the protection method and the greening protection method is considering cost and risk with new construction. We adopt the protection method by rock bolt and rope net. In this study, at first, we establish the vegetation base suitable for growth of plants which can be use together with the protection method. And then, we install many kind of the vegetation base that gave the vegetation on a model shotcrete. Finally, we compared the rates of water retention and vegetation growth.

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In Japan, in the high economic growth period in 1960’s, a great number of slopes were formed to construct many roads. Now, the slopes have been aging, it is important to estimate the health of the aging slopes and maintain slopes effectually. So we usually carry out seismic wave method, surface wave method, electric method and so on. However, there is not the technique to compound and interpret the result of each geophysical exploration. Therefore, we notice to self-organizing maps (SOM) used widely in a field of the information processing engineering, and tried to interpret multidimensional data by integrating. In this paper, we classified the ground property by self-organizing maps. The classification result is relatively conformal with boring data. Therefore, it is recognized that it can be used to improve the interpretative accuracy of compound geophysical explorations. And, it can be shown that this technique is effective to estimate of the ground property of the aging slope.

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In this research, we chiefly proceed on-site measurement and analysis to examine how the pumping wells influence groundwater properties. The examined region is surrounded by mountains formed by a bowl shaped depression in the Paleozoic strata and granite. The paleozoic strata basin rock is an impermeable bed upon which there is a permeable diluvium and then alluvium. It is estimated a lot of groundwater is saved. However, if an excessive pumping is continued, it can cause the exhaustions of the groundwater and the subsidence, and especially multiple wells which take a large amount of water in a small area are considered to have a great impact. We established a 3D model for groundwater and make suggestions for the adequate management of the groundwater by a pumping simulation analysis. This simulation was the subject of which was a pumping well for water service - water levels for one pump were large. As a result, it can be seen from our research that the fluctuation of water level caused by group wells has been reproduced accurately by using our model.

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We usually carry out geophysical explorations for slope conditions. However, there is no technique to compound and interpret the result of each geophysical exploration now. Therefore, we classified the ground property by self-organizing maps (SOM). The classification result by SOM is relatively conformal with boring data. Therefore, it is recognized that it can be used to improve the interpretative accuracy of compound geophysical explorations.

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At first, we regarded a decrease of clod strength as decrease of frictional coefficient on this analysis. As a result, we have been able to calculate the decreasing rates of frictional coefficient, and the start speeds. Moreover, we could recognize that collapse soil’s distance depends on frictional coefficient, and we could estimate the most dangerous slope among all cases.

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The purpose of our study is to maintain the groundwater resource that supports the life and culture of people in Fushimi ward. So, we need to make a 3D model for groundwater from the viewpoint of groundwater conservation as a general assessment method. For the purpose of groundwater conservation, we would like to use this simulation model as a general assessment to protect the resource and the environment of groundwater.

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In our study, we chose the vegetation base which was suitable for greening of shotcrete slope considering landscape and environment from the test results. We confirmed the water retention rate and the cover degrees in a test.

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In this study, we tried excavation simulation of shallow tunnel by using distinct element method with high utility for a discontinuous ground. The focus of our research is actual collapse accident of tunnel, and we examined the presence of the collapse by setting conditions of underground water and the invert support, etc. As a result of the simulation, an analysis model collapsed when underground water exists and invert is not closed as the actual phenomenon.

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In this research, we chiefly proceed on-site measurement and analysisto examine how the pumping wells influence groundwater properties. Thearea of the analytical model is located in the southern part of Kyotoprefecture. The examined region is surrounded by mountains formed by abowl shaped depression in the basin rock, which forms an impermeable bedupon which there is permeable sand and gravel. It is estimated a lot ofgroundwater is saved. However, if excessive pumping is continued, it mayexhaust the groundwater and result in subsidence. This is especiallytrue when multiple wells take a large amount of water in a small areacausing considerable impact. We established a 3D model for groundwaterand made suggestions for the adequate management of the groundwaterbased on pumping simulation analysis. The subject of this simulation wasa pumping well for water service - water levels for one pump were aparticularly large pump pumped a large amount of water compared to theother pumps. As a result, by using our model for this present study itcan be seen from this simulation that the fluctuation of water levelgroup wells affect accuracy.

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It is difficult that to set a clear standard concerning the design, because tunnels are excavated in various geotechnical conditions. So it is required that analytical method that can appropriately reproduce the mechanics behavior on the natural ground. In this study, the purpose of our research is established the analytical simulator in multilayered ground by using DEM. Then, the focus of our research is actual collapse accident of tunnel, and we examined the presence of the collapse by setting conditions of underground water and the invert support, etc. As a result of the simulation, an analysis model has collapsed when underground water exists and non-closing invert as the actual phenomenon.

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近年、老朽化した法面の健全性評価において、種々の物理探査手法が注目されている。しかしながら、単独の物理探査手法によって得られる物理量では地山状態を解釈するには限界があり、複数の物理探査手法を用いて総合的に解釈することが望まれる。そこで本研究では、同一斜面において複数の物理探査を用いて連続的に計測し、計測された個々の物理量もしくはこれらを組合せた複合評価手法を用いて、それらの時系列解析による健全性評価手法を構築することを目的とする。

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老朽化法面の健全度の調査において，複数の物理探査法を用いて総合的に評価する方法が注目されている．しかしながら，現在のところ複数の物理探査を総合的に解釈する手法は確立されておらず，技術者の専門的な知識や経験に基づく高度な判断が要求され，物理探査の解釈にばらつきが生じる可能性があるのが現状である．そこで本研究では，情報処理工学の分野で幅広く使われている自己組織化マップ(Self-Organizing Maps : SOM)を用いて，原位置において実施された複数の物理探査の結果をクラスタリングし，総合的に解釈する手法の提案を試みた．SOMによる地盤評価事例は，岩盤斜面の危険度評価や，南海トラフ沈み込み帯における断層面の物性評価や，堤防内土質性状の分類の幾つかあるのみで，ここでは老朽化法面の地盤性状評価の適応性について検討した．SOMを用いて分類した結果は，ボーリング調査で明らかとなった岩盤の割れ目による品質評価(Rock Quality Designation : RQD)，岩種および岩級区分と関連付けられることから，本手法は，老朽化法面の岩盤性状を把握するための複合物理探査の評価解釈精度の向上に有効であることが示せた．

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多くの酒造会社が立ち並ぶ伏見地域は，水質的にも優れた伏流水が酒造りの伝統を支えている．しかし，平成19年度から酒造会社が密集する伏見地域で，合流式下水道管の改善を目的とした下水管の敷設工事が施工された．本研究は，その地下構造物が周辺の井戸の地下水位に及ぼす影響を検討したものである．最初に，伏見地域においての解析地層モデルを作成し，浸透流解析を行い，伏見地域における地下水流動挙動を推定した．解析の精度を検討するために，実際の地下水頭と解析結果より得た地下水頭を比較することにより，モデルの妥当性の検証を行った．そして，当該地域に新たに施工された地下構造物が及ぼす周辺の井戸に対しての，地下水位への影響が少ないことを解析結果より確認した．

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In Japan, in the high economic growth period in 1960’s, a great number of slopes were formed to construct many roads. Now, the slopes have been aging, it is important to estimate the health of the aging slope and maintain slopes effectually. So, in situs, we usually carry out seismic wave method, surface wave method, electric method, electromagnetic wave method, frequency domain electromagnetic method and so on. However, there is not the technique to compound and interpret the result of each geophysical exploration in a numerical formula of the engineering now. Therefore, we notice to self-organizing maps (SOM) used widely in a field of the information processing engineering, and tried to interpret multidimensional data by integrating. In this paper, we classified the ground property by self-organizing maps. The classification result is relatively conformal with boring data. Therefore, it is recognized that it can be used to improve the interpretative accuracy of compound geophysical explorations. And, it can be shown that this technique is effective to estimate of the ground property of the aging slope.

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It is difficult that to set a clear standard concerning the design, because tunnels are excavated in various geotechnical conditions. Therefore, in general, the design is carried out still experientially, so it is required that analytical method that can appropriately reproduce the mechanics behavior on the natural ground. In this study, we tried excavation simulation analysis of shallow tunnel in multilayered ground using DEM, and the purpose of our research is established the analytical simulator in multilayered ground. Then, the focus of our research is actual collapse accident of tunnel, and we examined the presence of the collapse by setting conditions of underground water and the invert support, etc. We decided the analytical parameters by trying the simulation analysis of biaxial compression test using DEM, before we start the excavation simulation. As a result of the simulation, an analysis model has collapsed when underground water exists and non-closing invert as the actual phenomenon.

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In Japan, in the high economic growth period in 1960’s, a great number of slopes were formed to construct many roads. Now, the slopes have been aging, it is important to estimate the health of the aging slope and maintain slopes effectually. So, in situs, we usually carry out seismic wave method, surface wave method, electric method, electromagnetic wave method, frequency domain electromagnetic method and so on. However, there is not the technique to compound and interpret the result of each geophysical exploration in a numerical formula of the engineering now. Therefore, we notice to self-organizing maps (SOM) used widely in a field of the information processing engineering, and tried to interpret multidimensional data by integrating. In this paper, we classified the ground property by self-organizing maps. The classification result is relatively conformal with boring data. Therefore, it is recognized that it can be used to improve the interpretative accuracy of compound geophysical explorations. And, it can be shown that this technique is effective to estimate of the ground property of the aging slope.

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This study concerns the protection method and the natural maintenance of aging shotcrete. In Japan, in the high economic growth period in 1960’s, a great number of slopes were formed to construct many roads and most slope protection methods were to cover shotcrete on the slope. In recent years, with concerns about the environmental and landscape, the construction of shotcrete is decreasing. However, even now about 7,000,000㎡of shotcrete is laid every year, and it is predicted that the total amount of shotcrete is enormous. Now, about 60 years passes after a great number of shotcrete was laid, and shotcrete have been aging. Therefore, we suggested the method which construct for directly aging shotcrete in the protection method and the greening protection method is considering cost and risk with new construction. We adopt the protection method by rock bolt and rope net. In this study, at first, we establish the vegetation base suitable for growth of plants which can be use together with the protection method. And then, we install many kind of the vegetation base that gave the vegetation on a model shotcrete. Finally, we compared the rates of water retention and vegetation growth.

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In recent years, about 1000 slope failures occur every year in Japan, and about 90% of them are superficial slope failures that occur within 3 meters from the surface. Therefore this research suggests a new natural method for the slope stability. It takes environment and landscape into consideration, and can prevent superficial slope failures from occurring. Reinforcement members used in this method are rock-bolts, unit-nets, and pressure-plates. And we tried to preserve existing trees as much as possible. The purpose of this research is to establish more accurately designed method, and so the shearing test by the model of 1/10 scale was conducted. We made a model ground with reinforcement materials in shearing box and made it sheared by automatic load machine. Then we measured shear load with loadcells measures shear load and strain gauges attached to rock-bolt and unit-net. In the past research, we made it clear how the change of the effect of diameter of pressure plates gave to reinforcement mechanism in this method on sandy soil ground. The result was that enlarging diameters of pressure plates increases reinforcement effect comprehensively in this method. Shearing test was carried out on cohesive soil ground in addition to sandy soil ground in this research, and we examined how the difference of the grain size made the effect to the reinforcement mechanisms. As a result, it was clarified that the depression effect of transformation became bigger as the diameters ofpressure plates was longer also in the mixed soil ground.

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A large number of shotcrete slopes that were constructed in Japan during the 1970’s are now more than 30 years old, and there has been a significant degree of deterioration. Therefore, it is important to develop a method for monitoring the stability and the durability of these slopes. In this paper, we propose a technique that converts seismic velocity and electric resistivity data to porosity and saturation, which is then used to monitor weathering and groundwater fluctuation behind the slope. The evaluation results of this methodology confirm that the distribution of porosity and saturation of rock mass around the evaluated slope arrived at by this conversion system agree with those of the actual rock mass conditions evaluated using boring samples. In addition, it was possible to monitor the signs of seasonal variation and weathering in the ground by performing monitoring using this methodology over a period of multiple years.

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Kyoto city has various traditional cultures and industries. One of these is the production of Japanese sake, for which Fushimi-Ward is famous. This area has a lot of underground water of good water quality suited to making Japanese sake, and consequently. However, the new construction of a combined sewer system was started 3 years ago in Fushimi-Ward. The purpose of our study is to establish a 3D management model for underground water and examining the influence of the subterranean construction on the surrounding underground water level. The underground water of the Fushimi area has been protected by the Fushimi sake brewing union. They protect underground water from various potentially harmful construction projects. We believe that this management model will be useful in predicting the effects of the underground water levels. And, it is recognized that in the context of this model the new sewer does not cause adverse effects on underground water levels. We have to protect the underground water in the Fushimi area and in order to protect traditional Japanese sake.

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It is difficult that to set a clear standard concerning the design, because tunnels are excavated in various geotechnical conditions. Therefore, in general, the design is carried out still experientially, so it is required that analytical method that can appropriately reproduce the mechanics behavior on the natural ground. In this study, we tried excavation simulation of shallow tunnel by using distinct element method with high utility for a discontinuous ground. Using an analytical model of over burden 1D and 2D, we reproduced excavation of the invert by removing the particles in the invert part in the arbitrary time step, and examined the influence the time change of excavation gave to the natural ground in the surrounding.

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Kyoto city has various traditional cultures and industries. One of these is the production of Japanese sake, for which Fushimi-Ward is famous. This area has a lot of underground water of good water quality suited to making Japanese sake, and consequently. However, the new construction of a combined sewer system was started 3 years ago in Fushimi-Ward. The purpose of our study is to establish a 3D management model for underground water and examining the influence of the subterranean construction on the surrounding underground water levels. And, it is recognized that in the context of this model the new sewer system does not cause adverse effects on underground water levels. We have to protect the underground water in the Fushimi area and in order to protect traditional Japanese sake.

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In this study, we tried to clarify the reinforcement mechanism of a natural stability method by shearing test. The result that enlarging diameters of pressure plates increases reinforcement effect of this method comprehensively was obtained.

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A large number of the shotcrete slopes constructed during Japan’s post-war economic boom are now more than 30 years old, and their structural deterioration is an ongoing problem. Therefore, it is necessary to accurately assess the stability and durability of these existing slopes. In this paper, we propose a technique to evaluate rock weathering and groundwater fluctuation behind the slope using a conversion analysis of seismic velocity and resistivity to porosity and water saturation of rocks. In the conversion analysis, porosity and water saturation of rocks are estimated with a non-linear optimization method based on the empirical relations of seismic velocity and resistivity to porosity and water saturation. This proposed technique was applied to a shotcrete slope along a road and verified with boring data. The porosity and water saturation estimated with the conversion analysis of seismic P-wave velocity and resistivity measured at the slope were interpreted to evaluate the rock grade and groundwater distribution of the rock behind the shotcrete slope. The interpretation was verified with the boring data to clarify the applicability of the proposed technique.

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Language：Japanese  

In this paper, we try the simulation analysis of excavation of shallow tunnel in multilayered ground using DEM. A simulation model is composed of 5 layers that values of physical properties are different, and different analytical parameters are gave to each layer. These values are decided by doing the simulation analysis of biaxial compression test by DEM in advance of excavationg simulation. Using the ground model and these analytical conditions, we tried to simulate a tunnel excavation, and it is recognized that the deformation of surrounding ground of tunnel and the effect of ground surface are inhibited by improving the layers of low-stiffness.

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河川堤防の安全性を検討する場合、対象区間においてボーリング調査をポイント的に行いボーリング間の地層については補完的に設定していることが一般的と思われる。しかし、ボーリング地点の間隔が長い場合、その区間内がボーリング結果から補完した地層区分どおりの状態であるとは限らず、脆弱層の見落とし等が懸念される。本研究において周波数領域電磁探査法（Frequency Domain Electromagnetic Method：以下、略してFDEM探査法と呼ぶ）は、従来のFDEM探査機を改良開発したもので、探査機を地表面に置くだけで非破壊的に直下の比抵抗分布を迅速に探査することが可能である。したがって、河川堤防のような長い区間の地層状態を比抵抗分布から推定する手法に適していると思われ、比抵抗は含水比や粘土や礫の含有量等に相関があることからボーリング結果とキャリブレーションしながら解析すれば精度の高い地層区分や脆弱層の位置を推定できるものと考えられる。本研究においては、新しく開発されたFDEM探査機と推定原理に関する理論的な考察を述べるとともに数ヶ所の河川堤防で行った現位置における探査結果から、本手法の適用性について検討した。

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本研究では、京都府南山城地方でも地下水への依存度が高い城陽市に着目した。城陽市では現在上水道用水のうち地下水の占める割合は約80%にのぼっている。したがって、地下水汚染に対しては、十分な対策が必要となる。ここでは、城陽市域における3次元地質モデルを作成するとともに、3次元地下水浸透流解析を行い、更には汚染を想定した移流・拡散挙動についても検討した。

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A large number of the shotcrete slopes constructed during Japan’s post-war economic boom are now more than 30 years old, and their structural deterioration is an ongoing problem. Therefore, it is necessary to accurately assess the stability and durability of these existing slopes. In this paper, we propose a technique that converts data from seismic velocity and electric resistivity to porosity and saturation, and we used the proposed technique to evaluate weathering and groundwater fluctuation behind the slope. Evaluation data from boring samples indicates that the distribution of porosity and saturation of rock mass around the slope as calculated using the proposed conversion system are highly similar to those of the real rock mass conditions.

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In this paper the study is slope stability. 70% of national land of Japan is mountain district, but countermeasures of slopes with the potentiality of collapse have not been progressed yet. Therefore, many slope failures occur caused by heavy reins or earthquakes in these years. Most slope protection methods were to cover shotcrete on the slope in 1960’s. However, the slope covered shotcrete have been deteriorating. Therefore, it is important to develop an effective slope stability method. Furthermore, it is necessary to consider environmental problems such as global warming. A new slope stability method to maintain natural environment on slopes is suggested in this paper. In the method, existing timber is hardly cut down. The method has advantage of cost and construction. Reinforcement materials of the method are rock-bolt, pressure-board and unit-net. The direct shear test was conducted. To get higher slope stability efficacy, the test was conducted with 2 types of the diameter of pressure-board. The objective of this study is to evaluate quantitatively the influence of pressure-board on the reinforcement mechanism.

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The collapse accident of shallow tunnel occurred under construction in Japan, and landslides of the volume of about 6,700 m3 flowed into the tunnel. Geology of the collapse location is composed of 5 layers, and the upper side of the tunnel is used as field of rice. It is supposed that factors of this collapse accident were low earth covering, distribution of sandy soil layer and cohesive soil layer that are low-stiffness, and so on. However, its details are not clarified. In this paper, we try to clarify the mechanism of this collapse in modeling of ground composed of 5 layers using two dimensional DEM. In this analysis method, value of physical properties of simulation object is controlled by interparticle parameters. Then, in advance of simulation of excavation, we tried the simulation analysis of biaxial compression test by DEM, and examined the parameters that are expressible of the simulation object. Using this analytical condition, we tried to simulate excavation of the shallow tunnel, and to examine the differences of ground behavior by geological structures. As the result of this analysis, it is recognized that subsidence of ground surface is inhibited by improving the layers of low-stiffness.

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This research is monitoring the ground condition inside the aging slope. The purpose of this research is to consider the value of the monitoring method with the ground evaluating system to estimate the aging slope health. In Japan, years of high economic growth in 1960’s, a great number of slopes were formed to construct many roads and most slope protection methods were to cover shotcrete on the slope. Now, slopes covered shotcrete have been aging. Therefore, there is a possibility that the slope failures occur due to the action of the weather and natural disaster such as climate variations, heavy rainfall and earthquake. It is important to establish the method monitoring the ground condition inside the slope to estimate the aging slope health and to effectually maintain slopes. In this research, first, we examined the ground condition in situs using seismic method and electric prospecting. Second, we changed each measured results of geophysical explorations into the porosity and saturation distribution with the ground evaluating system. This system uses the seismic velocity and the porosity - saturation relational expression (Wyllie 1956) and the resistivity and the porosity - saturation relational expression (Archie 1941).

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The Kyoto city has various traditional cultures and industries. One of these is the production of Japanese sake, for which Fushimi-Ward is famous. The purpose of my study is to establish a 3D management model for underground water. This area has a lot of ground water of good water quality suited to making Japanese sake, and consequently. The underground water of the Fushimi area has been protected by the Fushimi sake brewing union. They are famous for preventing the construction of the Nara subway suggested in the 3rd year of Showa. They protect underground water from various potentially harmful construction projects. However the construction of a sewer was started last year in Fushimi Ward. They worry about the effects of the construction. I believe that this management model will be useful in predicting the effects of the underground construction. This 3D model will be needed to save the underground water in the Fushimi area. We have to protect the underground water in the Fushimi area and in order to protect traditional Japanese sake.

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This research is monitoring the ground condition inside the aging slope. The purpose of this research is to consider the value of the monitoring method with the ground evaluating system to estimate the aging slope health. In Japan, years of high economic growth in 1960’s, a great number of slopes were formed to construct many roads and most slope protection methods were to cover shotcrete on the slope. Now, slopes covered shotcrete have been aging. Therefore, there is a possibility that the slope failures occur due to the action of the weather and natural disaster such as climate variations, heavy rainfall and earthquake. It is important to establish the method monitoring the ground condition inside the slope to estimate the aging slope health and to effectually maintain slopes. In this research, first, we examined the ground condition in situs using seismic method and electric prospecting. Second, we changed each measured results of geophysical explorations into the porosity and saturation distribution with the ground evaluating system. This system uses the seismic velocity and the porosity - saturation relational expression (Wyllie 1956) and the resistivity and the porosity - saturation relational expression (Archie 1941).

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The research of my paper on the Ground Water is to predict the extent of the pollutant source. This research paper purposes, by making semi 3D model, to analyze semi 3D seepage flow, to predict ground water flow and to analyze the advection and diffusion of pollutant. The area of the simulation model is located in the southern part of Kyoto- prefecture, it has a typical ground water basin shape. We made the analysis of the each seepage flow by using semi 3D model we have made. The next, we made the simulation analysis of advection and diffusion of pollutant source to predict the extent of pollutant source. This pollutant source for this research is VOC and arsenic.

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In this paper the study is slope stability. 70% of national land of Japan is mountain district, but countermeasures of slopes with the potentiality of collapse have not been progressed yet. Therefore, many slope failures occur caused by heavy reins or earthquakes in these years. Most slope protection methods were to cover shotcrete on the slope in 1960’s. However, the slope covered shotcrete have been deteriorating. Therefore, it is important to develop an effective slope stability method. Furthermore, it is necessary to consider environmental problems such as global warming. A new slope stability method to maintain natural environment on slopes is suggested in this paper. In the method, existing timber is hardly cut down. The method has advantage of cost and construction. Reinforcement materials of the method are rock-bolt, pressure-board and unit-net. The direct shear test was conducted. To get higher slope stability efficacy, the test was conducted with 2 types of the diameter of pressure-board. The objective of this study is to evaluate quantitatively the influence of pressure-board on the reinforcement mechanism.

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Geophysical exploration for such as tunnel construction is usually used on seismic method and electric method. However, seismic velocity and electric resistivity directly are not connected with a design for tunnel construction. Grasping the nature of rock masses, for example effective porosity and saturation, is very important for the design of tunnel. In this paper, new estimation method of tunnel construction by joint inversion using seismic velocity and electric resistivityare proposed. As the result, it is recognized that the distributions of porosity and saturation of rock mass around tunnel by this inversion system correspond with that of the real rock mass conditions.

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As is known, there are many fractures and discontinuities in rock slope, and these are often the cause of failure. In this paper, we attempt simulation analysis and visualization of discontinuity by DEM. However, it is difficult for DEM to express both of the continuum and discontinuities. So, we introduce the concept of bonding force, and it is made to be an applicable analysis method for the continuum. Using this analysis method, we try to simulate a failure rock slope, and to visible progress of discontinuities. As the results of this analysis, it is recognized that the discontinuities are formed surface and internally the rock slope. Moreover, the factors of failure can be visualized.

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Language：Japanese  

A lot of shotcrete slopes mainly constructed in Japan by 1970's pass through over 30 years, and their deterioration processes continued. So, it is required to grasp efficiently the stability and the durability of these slopes. In this paper, using our proposed technique that converted from seismic velocity and electric resistivity to porosity and saturation, we tried to evaluate weathering and groundwater fluctuation behind the slope. As the result, it is recognized that the distribution of porosity and saturation of rock mass around slope evaluated by this conversion system agree with those of the real rock mass conditions by boring results.

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国道42号の同一法面を対象に各種の物理探査手法を使用した実証実験の中から、弾性波探査を用いた法面調査結果を報告し、弾性波探査手法の法面健全性評価への適用性について検討したものである。

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京都府南山城地域では、昔から豊富な地下水資源に恵まれ、農業用や工業用、生活用水に地下水を使用してきた。今日では、上水道水源の約8割を地下水に依存しており、また、田畑が広がる区域ではいたるところに井戸が確認される状況となっている。南山城地域で地下水汚染が発生することは重要な問題であるといえる。京都盆地は基盤岩にお椀状に囲まれており、その上に良質な帯水層を含む大阪層群や沖積砂礫層が載っている。また蓄積された地下水は、木津川、桂川、宇治川の3河川合流地点である天王山と男山の間からしか流出するところがなく、このことから京都盆地が豊富な地下水を有していることが推測される。本研究では、多くの地下水利用がなされている京都府南山城地域の特に城陽市に着目し、その地域においてシミュレーションモデルを構築し、浸透流解析、移流拡散解析を行い、汚染源の移動について検討する。

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The study in this paper is the slope stability. Although many slopes are prone to collapse, countermeasures against slope failures have not been progressed yet in Japan. Most slope protection methods were to cover shotcrete on the slope in 1960's. However, the slope covered shotcrete have been deteriorating. Therefore, the slope failures frequently occur due to the natural disaster such as heavy rainfall and earthquake. It is important to develop an effective slope stability method. Moreover, it is necessary to consider environmental problems such as global warming. A new slope stability method to maintain natural environment on slopes is suggested in this paper. The method has advantage of the cost and construction. The rock-bolt, the pressure-bored and the unit-net as reinforcement are used in the method. The model shear test was conducted. The test sample is one collected from a slope. The experimental conditions on water content and the content for clay fraction were changed for each case. The objective of this study is to evaluate quantitatively the influence of ground physical properties on the reinforcement mechanism.

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The research of my paper on the Ground Water is to predict the extent of the pollutant source. These research paper purposes, by making 2D model, to analyze two dimensional seepage flow, to predict ground water flow and to analyze the advection diffusion of pollutant. The area of the simulation model is located in the southern part of Kyoto prefecture, it has a typical ground water basin shape. First, I made the 2D model with examining the material of the stratum, and divided 3 kinds of layers. That is divided into alluvial formations, clay formations, and, diluvial formations from the ground level. It is because that the most important purpose of this study is to the extension of the pollution in multiple layers. I made the analysis of the each seepage flow to get the speed of a moving fluid by using 2D model I have made. The next, I made the simulation analysis of advection Diffusion of pollutant source to predict the expansion of pollutant source. This pollutant source for this research is mercury.

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As is khnouwn, there aer many fractures in rock slope, and there fractures are often the cause of failure. Especially, the mechanism of sliding failure depends on fractures in rock slope. In thispaper, Three-dimensional numerical simulation for sliding failure by distinct element method are carried out. In relation to this simulation, the interparticle bonding force can tried to be expressed by bonding theory. It is tried to be simulated an actual sliding failure of rock slope. As the results of this simulation, it is recognized that this simulation can be expressed on this sliding failure phenomena. Moreover, the process of sliding failure can be visualied.

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Language：Japanese  

In case of urban NATM method for sandy soil ground of the urban areas in Japan, the behaviors of ground are complicated and uncertain during an excavation. The purpose of this research is a simulation of deformational behavior for a shallow tunnel using distinct element method, which is clearly beneficial in a behavior of large deformation and shearing in excavation of sandy soil ground. The, deformation and stress distribution of behavior of ground are considered by the difference between thicknesses of earth covering in an excavation of a tunnel, snd then an influence in a behavior of ground soil about a distance between tunnels during an excavation is considered.

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Language：Japanese  

Landslide areas were evaluated using qualification theory 2 and geometric mean. To evaluate the areas, inclination, NDVI, geological features, and azimuth, which are considered closely related to the landslide, were used as explanatory variables. Comparing with these results, two indices were calculated, one is the overlooking ration, which is estimated as non-landslide areas for actual landslide-occurred areas, the other is overextraction ratio, which is estimated as landslide ares for actual non-landslide areas, As a result, at the overlooking ration, the geometric mean and the qualification theory 2 provide almost equal result, But the overextraction ratio, the former provides better results than the latter.

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地下水資源が人類の発展に果たしてきた役割は計り知れない。地下水が古くから利用されてきたのは、水資源として極めて魅力的な性質を備えているからである。その特徴を示すと、安定性、恒温性、経済性などが挙げられる。 地下水を利用してきた人類も数千年の間、何のトラブルも起こさなかったが、最近の問題として地下水汚染が挙げられる。地下水汚染とは、地下水中に重金属、有機溶剤、農薬、油などの各種の物質が自然環境や人の健康、生活へ影響を与える程度に含まれれている状態をいう。汚染の原因は人為的または自然由来であるが、原因が不明とされている事例も多い。 本研究は、多くの地下水利用がなされている地域に着目し、その地域においてシミュレーションモデルを構築し、地下水汚染が発生した場合の汚染源の動きについて把握し、地下水汚染対策に役立てることを目的とし、そのシミュレーションモデルの構築を目指した。

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The area of the analytical model is located in the southern part of Kyoto prefecture, it has a typical ground water basin shape and three rivers flow through it. The rivers flow into the area between two mountains, then flow out to Osaka. Due to the fact that the underground water in the basin flows out from this point only, it is estimated that abundant underground water is saved in the Kyoto basin. This research is focused on Joyo city which has long used plenty of underground water for the public, agricultural and industrial water supplies. In recent years, excessive pumping has caused subsidence and the depletion of water resources. This research purposes to establish a three dimensional groundwater flow model and make suggestions for the adequate management of the underground water by a pumping simulation analysis.

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As is known, there are many fractures in rock slope, and these fractures are often the cause of failure. Especially, the mechanism of sliding failure depends on fractures in rock slope. In this paper, we attempt to clarify the mechanism of slope failure in modeling of rock slope with discontinuities using three-dimensional distinct element method. However, it is difficult for distinct element method to express both of the continuum and the discontinuities. So, we introduce the concept of bonding force between particles into distinct element method, and it is made to be an applicable analysis method for the continuum. In the rock slope model in this analysis, the slope and the location of fractures can be arbitrarily set. The position of the fractures in the model is based on the result of the field investigation. And, the fractures were expressed by removing the bonding force. Using this analytical model, it is tried to simulate an actual sliding failure of rock slope. As the results of this analysis, it is recognized that this simulation can recreate this sliding failure phenomena. Moreover, the process of sliding failure can be visualized.

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Geophysical exploration for such as tunnel construction is usually used on seismic method and electric method. However, seismic velocity and electric resistivity directly are not connected with a design for tunnel construction. Grasping the nature of rock masses, for example effective porosity and saturation, is very important for the design of tunnel. In this paper, new estimation method of tunnel construction by joint inversion using seismic velocity and electric resistivity are proposed. As the result, it is recognized that the distributions of porosity and saturation of rock mass around tunnel by this inversion system correspond with that of the real rock mass conditions.

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As is known, there are many fractures in rock slope, and these fractures are often the cause of failure. Especially, the mechanism of sliding failure depends on fractures in rock slope. In this paper, we attempt to clarify the mechanism of slope failure in modeling of rock slope with discontinuities using three-dimensional distinct element method. However, it is difficult for distinct element method to express both of the continuum and the discontinuities. So, we introduce the concept of bonding force between particles into distinct element method, and it is made to be an applicable analysis method for the continuum. In the rock slope model in this analysis, the slope shape and the location of fractures can be arbitrarily set. The position of the fractures in the model is based on the result of the field investigation. And, the fractures were expressed by removing the bonding force. Using this analytical model, it is tried to simulate an actual sliding failure of rock slope. As the results of this analysis, it is recognized that this simulation can recreate this sliding failure phenomena. Moreover, the process of sliding failure can be visualized.

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Language：Japanese  

As is known, it is important to clarify the shear behavior of rock joint for the safty construction of rock structures. In this paper, the three dimentional simulation analysis of direct shear using distinct element method have been done. Especially, to reprent the tensile stress in rock mass, we tried to be applied on the bonding theory. As the results of this study, it is recognized that the results of this simulation with that of experiment.

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Language：Japanese  

As is known, there are many fractures in rock slope, and these fractures are often the cause of failure. Especially, the mechanism of sliding failure depends on fractures in rock slope. In this paper, Three-dimensional simulation analysis and visualization for sliding failure by distinct element method are carried out. In relation to this simulation analysis, the tensile force rock mass can be tried to be expressed by bonding theory. It is tried to be simulated an actual sliding failure of rock slope. As the results of this analysis, it is recognized that this simulation can be expressed on this sliding failure phenomena. Moreover, the process of sliding failure can be visualized.

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Language：Japanese  

In resently , the construction of shallow tunnels in big urban areas are increasing from the point view to be useful development in the urban space. However, it can not be clearfied that the mechanical behavior of the excavating shallow tunnels are much complicated. In this paper, it is tried to estimate the mechanical behavior of shallow tunnel into sand during excavation by Distinct Element Method. Especially, the simulation of surface settlement each depth are done.

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広域性・同時性・周期性といった特徴を有する衛星マルチスペクトルデータを利用し、斜面崩壊に関わると考えられているさまざまな要因の因果関係を数量化理論Ⅱ類により解析し、斜面崩壊予測への衛星マルチスペクトルデータの適用性について検討を試みている。そして、その結果を基に斜面崩壊危険性評価図を作成し、斜面崩壊危険性評価システムを構築することにより、未然に危険斜面を特定することを目的としている。

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As is known, there are many fractures in rock slope, and these fractures are often the cause of failure. Especially, the mechanism of toppling failure depends on fractures in rock slope. In this paper, Two-dimensional simulation analysis and visualization for toppling failure by distinct element method are carried out. In relation to this simulation analysis, the tensile force of rock mass can be tried to be expressed by bonding theory. The rock slope model with this analysis can be arbitrarily setting the slope shape and the location of fractures. The position of the fractures in the model is based on the result of the field investigation. And, the fractures are expressed by removing the bonding force. Using this analytical model, it is tried to be simulated an actual toppling failure of rock slope. As the results of this analysis, it is recognized that this simulation can be expressed on this toppling failure phenomena. Moreover, the proceternass of toppling failure can be visualized.

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The characteristic of the groundwater flow in a rock slope primarily depends on rock joint sets. In particular, the groundwater flow in a rock slope which has random joint sets is very complicated, and the specific methods which to monitor this flow have not been developed. In our past research, the systematization of geological evaluation technique that converted from seismic velocity and electric resistivity to porosity and saturation was proposed. In this paper, using this proposed technique, we tried to monitor the groundwater flow behavior during rainfall in rock slope site by changing of saturation in a rock slope.

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城陽市の位置する京都府南山城地方は、京都盆地の南部に位置し、桂川、木津川、そして琵琶湖を水源とする宇治川の３河川が京都～大阪府境である男山と天王山の間で合流している。この地方は、周囲を基盤岩類の山地で囲まれ、その基盤岩類の上に沖積層や洪積層が厚く堆積しており、典型的な地下水盆構造を呈している。よって、古くから上水道用だけでなく、農業用、産業用にも利用されてきた。本研究では、地下水への依存度が高い城陽市に着目し、当地域における地下水揚水シミュレーションモデルの作成を行い、本モデルの有効性に関して検討したものである。

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The characteristic of the groundwater flow in a rock slope primarily depends on rock joint sets. In particular, the groundwater flow in a rock slope which has random joint sets is very complicated, and the specific methods which to monitor this flow have not been developed. In our past research, the systematization of geological evaluation technique that converted from seismic velocity and electric resistivity to porosity and saturation was proposed. In this paper, using this proposed technique, we tried to monitor the groundwater flow behavior during rainfall in rock slope site by changing of saturation in a rock slope.

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Language：Japanese  

Geophysical exploration for tunnel construction is usually used on seismic method and electric method. However, seismic velocity and electric resistivity directly are not connected with a design for tunnel construction. Grasping the nature of rock masses, for example effective porosity and saturation, is very important for the design of tunnel. In this paper, new estimation method of tunnel construction by conversion analysis seismic velocity and electric resistivity are proposed. As the result, it is recognized that the distributions of porosity and saturation of rock mass around tunnel by this analysis system correspond with that of the real rock mass conditions.

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In this paper, the establishment of the underground Thermal Energy Storage system with the effective utilization of the underground water is studied as one of the solution for these problems. The system effectively utilizes the cut-off walls installed at the time of the construction of underground building frames of high-rise buildings, saving the exhaust heat from the air conditioning in the underground aquifer in the building frames rather than releasing it into the air during summertime to utilize the exhaust heat in the wintertime, which can possibly lead to the establishment of the effective underground water utilization that contributes to both the energy saving measures and the countermeasure against heat-island phenomenon.

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Geophysical exploration for tunnel construction is usually used on seismic method and electric method.However,seismic velocity and electric resistivity directly are not connected with a design for tunnel construction.Grasping the nature of rock masses,for example effective porosity and saturation, is very important for the desingn of tunnel. In this paper,new estimation method of tunnel construction by joint inversion using seismic velocity and electric resistivity are proposed. As the result, it is recognized that the distributions of porosity and saturation of rock mass around tunnel by this inversion system correspond with that of the real rock mass conditions.

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Shield construction works are the most popular method employed at the Taiwan Mass Rapid Transit project and underground sewage projects. Joining of the shaft and the tunnel is generally high-risk work because of potential dangers, such as ground collapse and tunnel breaks. Accordingly, we measured the strength of geological improvement at the shield shaft and its P-wave velocities using a boring core and test piece. The test results show that the relationship between the unconfined compressive strength and P-wave velocities is very close. P-wave velocities can be used to estimate density. P-wave velocities will probably become a quality control test yardstick in future.

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Geophysical exploration for tunnel construction is usually used on seismic method and electric method.However,seismic velocity and electric resistivity directly are not connected with a design for tunnel construction.Graping the nature of rock masses,for example effective porosity and saturation,is very important for the design of tunnel. In this paper,new estimation method of tunnel construction by joint inversion using seismic velocity and electric resistivityare proposed.As the result,it is recognized that the distributions of porosity and saturation of rock mass around tunnel by this inversion system correspond with that of the real rock mass conditions.

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For the purpose of the effective urban development,construction opportunities of the city tunnel are increasing.But,the design techniques for the shallow and large section tunnel are unsettled.Generally,Finite Element Method is used for analysis of tunnel excavation.But,FEM is the analysis for continuity,so it is impossible to analyze discontinuities. Then,we tried to analyze the tunnel excavated actions by Distinct Element Method,the analysis for a discontinuity.Using this method,it enables to visualize ground action excavated,Distribution of displacement,compressive stress,and Subsidence of ground surface.This research simulates behaviors of the ground excavated by DEM,and considers the rational design of city tunnel.

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Geophysical exploration for tunnel construction is usually used on seismic method and electric method.However,seismic velocity and electric resistivity directly are not connected with a design for tunnel construction.Graping the nature of rock masses,for example effective porosity and saturation,is very important for the design of tunnel. In this paper,new estimation method of tunnel construction by joint inversion using seismic velocity and electric resistivityare proposed.As the result,it is recognized that the distributions of porosity and saturation of rock mass around tunnel by this inversion system correspond with that of the real rock mass conditions.

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本研究では、鉄筋類挿入補強土工法と落石防止ネットを応用し、樹木を極力伐採せずに自然斜面の安定化を図る新しい斜面安定工法を提案している。しかし、その効果や補強メカニズムの詳細については未解明の部分が残されている。ここでは、各種実験を実施することで本工法の効果および補強メカニズムを解明し、より制度の高い設計手法の確立を試みている。

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都市圏の住宅用地として開発された谷埋め盛土に代表される宅地造成盛土地盤は、強震時に大きく変動する。事実、過去の震災においてその被害が多数報告されている。1995年の兵庫県南部地震や新潟県中越地震では、都市域において多数の宅地谷埋め盛土が変形した。地震時谷埋め盛土斜面の崩壊は、谷底の横断面形状が大きな不安定化要因であることが確認されているが、崩壊発生機構は未だ明確にされていない。本研究では、詳細な現地調査に基づいた谷埋め盛土地盤の模型地盤を作成し、大型振動台実験を行った。

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Many kinds of rock test for engineering properties have been carried out to obtain rock kinetic properties. However it is difficult to visualize inside rock specimen during laboratory tests. This study's objective is to reconstruct true tri-axial tests using Distinct Element Method (DEM). At first, tri-axial compression test is carried out to know correlations between analytical properties and rock properties obtained through compression test like cohesion and internal friction angle. Next, true tri-axial test is simulated using properties above.The result of the simulation, it was clarified that the simulation result can reconstruct a laboratory test qualitatively.

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Geophysical exploration for tunnel construction is usually seismic method and electric method.BUt seismic velocity and resistivity directly do not be connected with a design for tunnel construction.Grasping the nature of rock masses,for example effecive porosity and saturation,is very important for the design of tunnelling.In this paper,new estimation method of tunnel construction by joint inversion using seismic velocity and resistivity is proposed.This inversion system are making clear effective porosity and saturation of rock masses.

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The technology which survey the geological condition of ahead for tunnel face in the mountain tunnel are well known for the seismic imaging ahead of tunnel face.However it is not classified this method can be applied to all rock mass conditions,it is important to research the degree of application of this technique because rock mass that including many fracture zones are existing many location in japan.In this paper ,the full wave inversion method is applied to the simulation date.This recognized that the seisemic imaging ahead of tunnel face using this method is very useful for the investigation of geological condition.

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Geophysical exploration for tunnel construction is usually seismic method and electric method. But seismic velocity and resistivity directly don’t be connected with a design for tunnel construction. Grasping the nature of rock masses, for example effective porosity and saturation, is very important for the design of tunneling. In this paper, new estimation method of tunnel construction by joint inversion using seismic velocity and resistivity is proposed. This inversion system are making clear effective porosity and of rock masses.

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本研究は、南山城地方の中でも上水道での地下水への依存度が高い八幡市に着目し、当地域における地下水シミュレーションモデルの作成を行い、揚水シミュレーションを行うことにより上水道用揚水井の維持管理を行っていくことを目的としている。

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In case of the excavation working of tunnel, the initial stress is opened wide, and local subsidence occurs all over the foundation and it becomes the cause by which this gives destruction and modification in a surrounding natural ground. And in order to grasp the mechanical behavior of shallow tunnel excavation in the intersection, two dimensional trap door tests have been developed and performed. With changing overburden pressures, the variation of vertical earth pressure acting on trap doors, the distribution of earth pressure and the settlement of ground surface have been measured. Then, it tried to perform the simulation of trap door test by Distinct Element Method, and from a viewpoint of the modification action of trap door or the model foundation, this research compared with the experiment result and the analysis result, and the validity was examined by it.

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反射法弾性波探査は、主に資源開発の分野において発展してきた技術であり、現在にいたるまで石油・天然ガスなどの資源探査において大きな成果を上げている技術である。しかし、近年の地盤防災・地下空間利用などの分野における物理探査の需要の高まりにより、これら土木の分野、おもに地盤工学の分野においても多く適用されるようになってきている。以下に、反射法弾性波探査のトンネル切羽前方探査における適用例と、地盤改良部の強度判定適用例を示す。

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In case of excavation working of underground, initial stress is opened wide, and local subsidence occurs all over the foundation and it becomes the cause by which this gives destruction and modification in a surrounding natural ground. And in order to grasp the mechanical behavior of shallow tunnel excavation in the intersection, two dimensional trap door tests have been developed and performed. With changing overburden pressures, the variation of vertical earth pressure acting on trap doors, the distribution of earth pressure and settlement of ground surface have been measured. Then, it tried to perform the simulation of a trap door test by Distinct Element Method, and from a viewpoint of the modification action of trap door or the model foundation, this research compared the experiment result and the analysis result, and the validity was examined by it.

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In this paper, simulation analysis for shearing behavior of rock discontinuity by distinct element method is proposed. The purpose is behavior of surface of scontinuity in the shear process and destruction situation of the roughness are clarified by numerical ulation. By using this analysis method, it became possible that the behavior of the test-piece model, the shear strength and the die ration behavior are analyzed. And, distribution situation of the internal stress in the shear process was clarified by visualizing the stress which affects each particle.

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This paper proposes an accurate imaging technique for looking ahead of tunnel face using three-component geophones with tunnel blasting as seismic sources. The procedure is as follow ; 1)Using three-component receivers installed on the tunnel walls, record the seismic signal reflected from the reflectors ahead of tunnel face; 2)Determine the direction of incidence of the reflected wave; and 3)Image the reflector using equi-travel time ellipsoid weighted by the incident direction of the reflected wave. The proposed technique is applied to datas otained at actual construction sites. The excavation of the tunnels proved that the results were consistent with the geological observation of the walls.

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The technique of various kinds of numerical analysis offered remarkable results tp explication of many rock mechanical phenomena. These techniques regarded a rock stratum as a continuum body and solved the governing equation of continuum mechanics by using finite difference method,finite element method and/or others. Using numerical analysis based on continuum mechanics, however,the simulations of destruction phenomena caused by elastic waves and on the other hand,the elastic wave propagation which generated by fracturing events are quite difficult. In this paper, we express a rock stratum by a granular body model and develop a simulation technique can simulate both wave phenomena and destruction phenomena at once. The DEM(discrete element method) simulation results are compared with finite difference solutions of elastic wave equation. Furthermore,we simulate Hopkinson effect by this proposed method.Hopkinson effect is famous as a destruction phenomenon caused by elastic wave propagation.

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The optical fiber is used on the main parts of optical communication technique. However in recently, it is recognized that the optical fiber is having the characterizations for strain sensor. In this paper, the fundamental tests in related with the output prosperties fir compression and tension of optical fiber were carried out and it is clarified that the relations between this output and strain of fiber is linear. Furthermore, the optical fiber is applied on the joint displacement measurment in rock mass slope. As the results, it is recognized that the displacement of joints can be measured high accuracy.

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

The seismic imaging method which surveys geological condition of ahead for tunnel face in the mountain tunnel are well known. However, it is not classified that this method can be applied to all of rock mass conditions,especially,in case of the rock masses including many fracture zones,it is important to research the degree of application of this technique because these rock masses are exciting many locations in Japan. In this paper, this technique was applied on Hida tunnel construction site. As the results,it is clean that the geological conditions can be obtained by this method.

DOI： 10.2208/jscej.2003.743_229

CiNii Books

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Other Link： http://hdl.handle.net/10112/2154

In case of constructing the mountain tunnel,geological survey such as seismic prospecting and electrical prospecting is often carried out. However, the support design based on these prospecting results is not quantitative,so it is often differ from actual geological condition. The other side,it is important from safety and economical efficiency to grasp accurately the geological condition beforehand in design and construction. In this paper,the systematization of geological evaluation technique that converted from seismic velocity and electric resistivity to porosity and saturation was discussed. As the results, the evaluation system of rock mass using the both of seismic velocity and electric resistivity are proposed, and it is recognized that this system can be applied on the in-site rock mass site.

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It is an important laboratory test the elastic waves of rock specimens are measured, and in general the velocities of two types elastic waves are used. In this paper, it is tried to develop the simultaneously measured system for P, S wave velocities and electric resistivity of a rock sample and its laboratory equipment. P and S wave are analytically found out from the recorded waves. And on the same time, the electric resistivity of this rock specimen is measured by geo science (GS) method. In the development of this system, the examination of sensor position was carried out. Furthermore, P, S wave velocities and electric resistivity obtained from this system are compared with these quantities given by the usual measurement methods. As the results, it is confirmed that this measurement system is useful for the various rock specimens.

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The measurement of elastic wave velocity is effective as the technique which grasps elastic characteristics of rock, and recently the evaluation by S wave is mainly carried out. In this paper, it is tried to develop the simultaneously measured system for P,S wave velocities and electric resistivity of a rock sample and to manufacture the laboratory equipment. In this system, P and S wave are analytically found out from the recorded waves. And on the same time, the electric resistivity of this rock specimen is measured by geo science method. Furthermore, P,S wave velocities and electric resistivity obtained from this system are compared with these quantities given by the usual measurement methods.As the results, it is confirmed that this measurement system is useful for the various rock specimens.

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On basis of the result, actual fracture rock slope optical fiber sensor V-shaped and injecting static crush agent in the rock slope, the rock mass was artificially displaced, and output chracteristics of that time optical fiber sensor were examined.

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In this paper,the effects of which the shear behavior of rock joint is depended on the magnitude of aperture condition are discussed.

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樹木を伐採せずに、かつ景観に配慮したロックボルト、ユニットネット併用による自然斜面の安定工法に関する基礎的な研究を行なった。

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In this paper, the relations among electric resistivity, seismic velocity, porosity and saturation of various rock specimens investigated by laboratory tests are clarified. In addition, it was attempted to combine the seismic velocity and the electric resistivity and to evaluate the porosity and saturation. As the results, it is recognized that this assessment method can be useful for geological survey.

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本研究では、17種類の硬岩の部類に属する岩石供試体（インタクト供試体）と、単一の不連続面を有する3種類の岩石供試体を用いて、室内において比抵抗値を測定して、比抵抗値と飽和度、間隙率の関係について検討した。また、単一不連続面を有する供試体では、不連続面間に湿潤させた濾紙を挟み、インタクト供試体と同様な実験を行った。このとき、不連続面に挟んだ濾紙の枚数を変化させて比抵抗値の測定を行った。これらのことから、岩石の比抵抗値に及ぼす飽和度、間隙率、不連続面の開口幅、不連続面の傾斜の影響について考察を行うとともに、岩石の地質学的分類と比抵抗値変化特性との関連性について検討した。また、岩石の飽和度、間隙率を含んだ岩石の比抵抗値を与える実験式を提案し、あるトンネル坑内の岩盤壁面で簡易比抵抗法によって計測された比抵抗値を提案した実験式に適用し、本実験式から実岩盤の物性値を評価できる可能性について検討した。

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斜面崩壊の原因として降雨等による地下水の変動があることは良く知られている。岩盤内の地下水の浸透あるいは流動挙動は、岩盤内に存在する亀裂や破砕帯を主な水みちとしていることから、これら不連続面部の性状に支配される。しかし、その挙動を精度よくモニタリングできる手法は、現時点において確立されておらず、崩壊危険箇所の推定のためにはこの分野の研究が必要とされている。電気探査比抵抗法による地下水計測として、これまでにも地中の水の流動による比抵抗変化をモニタリングしている研究1)～3)はいくつかみられるが、直接降雨の浸透状況を連続的に測定し、降雨の量と比抵抗の変化との関係について言及した論文は見受けられない。そこで本論文では、岩盤斜面内の破砕帯や地層境界部を対象として、斜面上に95mの計測線を設けてダイポール・ダイポール電気探査法によって降雨前後で連続的に見掛け比抵抗を計測し、各測点の見掛け比抵抗変化と降雨との関係について検討を行い、とくに破砕帯部におけるこれらの関係について考察した。

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

In the present paper, an accurate imaging technique for looking ahead of tunnel face by use of 3 components receivers is proposed.1)To receive the reflected waves from the geological boundaries by use of 3 components receivers.2)To detect the incident direction of reflected waves.3)To perform imaging by use of equi-travel time planes using the weight according to incident direction in order to decrease the generation of false image.The propesed technique was applied to the actual field data. Consequently, the imaging results showed a good agreement with the observation report after completion of tunnel.

DOI： 10.2208/jscej.2001.680_123

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Other Link： http://hdl.handle.net/10112/2121

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Before construction of any structures on surface or substance of alluvial clay layer, the cement mixing methods have been used frequently to construct an improved layer at certain depth of ground. However, the confirmation of improved layer is performed by only boring and laboratory testing. The present paper are discussed about the confirmation method using s-wave reflection method, and it is tried that the S-wave distribution of improved layera is obtained by velocity analysis. Furthermore, the relation between the uniaxial compression strength of improved layer specimens by boring and S-wave velocity of improved layer by the velocity analysis are discussed, and the continuous distribution of uniaxial compression strength on improved layer can be accurately obtained.

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The electrical resistivity prospecting is becoming very useful for ground investigation, because new computer methods have been developed and detailed electric resistivity distribution in ground can be indicated. However, characterizations of resistivity for rock mass are not clarified, and it is not sufficiently understood that the measured resistivity values can indicate conditions of rock mass. In this paper, using 17 types of intact rock specimens and 2 types of rock specimens with single joint, the resistivity of these specimens are measured in the laboratory. From these measured data, the relation between resistivity of the rock specimens, saturation, porosity and aperture of discontinuity are discussed. Furthermore, these results obtained by between tests are applied to rock mass assessment in a tunnel.

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When constructing tunnels, it is important to predict forward geological condition. But these detailed and quantitative informations cannot always be obtained from surface investigations. Because of this, the development of geological survey system ahead of face has been advanced. In the present paper, an analysis of the exploration ahead of tunnel face by using various artificial sources is proposed. This study was applied to the actual field data. The results of analysis by the seismic sources using hammer, iron ball and giant breaker show a good agreement with wall observation report after completion of tunnel.

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ABSTRACT: The factors of discontinuity plane which affect the shear behavior of rock joint are the strength of intact rock, roughness, aperture etc. In these factors, there is many researches in related with the roughness. However, although the aperture condition of rock joint is important factor, the many researches with this factor have not been performed. In this paper, the effects of which the shear behavior of rock joint is depended on the magnitude of aperture condition are discussed Especially, the numerical index representing the degree of the aperture condition with rock joints is opposed, and furthermore, we applied this index on the shear strength equation proposed by authors.

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The surface of cutting rock slope has exposed to alternate dry and wet conditions for a long time, and they are weathered. We developed direct shear testing apparatus that can expose soft rock specimen to alternate dry and wet conditions under constant under constant shear and normal stress, and are investigated about relationship between deformation properties and the shear behavior of soft rock under dry and wet conditions.

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Language：Japanese   Publisher：Kansai University  

The factors of discontinuity plane which affect the shear behavior of rock joint are the strength of intact rock, roughness, aperture etc. In these factors, there is many researches in related with the roughness. However, although the aperture condition of rock joint is important factor, the many researches with this factor have not been performed. In this paper, the effects of which the shear behavior of rock joint is depended on the magnitude of aperture condition are discussed. Especially, the numerical index representing the degree of aperture condition with rock joints is proposed, and furthermore, we applied this index on the shear strength equation proposed by authors.

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Language：Japanese   Publisher：Kansai University  

Before construction of any structures on surface or subsurface of alluvial clay layer, the cement mixing method is used frequently to construct a thin improved layer at certain depth of ground. However, the confirmation of improved layer is performed by only boring and laboratory testing. In the present paper, the confirmation method using s-wave reflection method, and the simulation analysis which as certain continuity of an improved thin layer is proposed. Especially in this analysis, the proposed method for the model at a thin layer of high velocity which lies between two layers of low velocity is examined, and the results of this simulation analysis are found to be applicable construction site.

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Hydromechaniacal behavior of rock masses is influenced in a decisive way by the presence of joints. It is largely responsible for seepage occurring through the rock mass and is the most sensitive elements with respect to deformation under stress changes. Hydromechanical studies of fractured rock masses must therefore pay special attention to the role of joints and to correct assessment of their properties. In this paper, an experimental study was carried out in granite specimens included a single joint with the purpose of obtaining the hydromechanical properties under hydrostatic stress conditions. The test results are then presented and analyzed, and the relation ship between the roughness of joint surface and hydromechanical properties are discussed.Key words: Single joint, Permeability, Discontinuity plane, Fractured rock

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Language：Japanese   Publisher：Kansai University  

Hydromechanical behavior of rock masses is influenced in a decisive way by the presence of joints. It is largely responsible for the seepage occurring through the rock mass and is the most sensitive elements with respect to deformation under stress changes. Hydromechanical studies of fractured rock masses must therefore pay special attention to the role of joints and to corrct assessment of their properties.In this paper, an experimental study was carried out in granite specimens included a single joint with the purpose of obtaining the hydromechanical properties under hydrostatic stress conditions. The test results are then presented and analyzed, and the relationship between the roughness of joint surface and hydromechanical properties are discussed.

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Before the underground structures such as tunnels and large caverns will be constructed, seismic prospecting and electrical prospecting for geological surveys are often executed. However, it is few that the velocity of elastic wave and the electric resistively obtained from these prospecting methods are directlyused to the design.In this paper, the relations among electric resistively, porosity and degree of saturation of various rock specimens were investigated by laboratory tests were compared with the field measurement data obtained by electric prospecting. As a result, it is clarified that the characterization of electric resistively of some rock cores can be applied on the estimation of in-situ rock mass.

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The optics fiber is usually used to the basic main lines of informatics transmission. In recently, it has been attracted special interest that the optics fiber can be used to the strain sensor lines applicable on the some characterizations of this fiber. In this paper, the observation methods of the displacement on rock slope by the fiber optics strain sensor are discussed. Especially, the some fundamental studies in related with the output characterizations of rock slope and the field measurements applied on the natural rock slope by the fiber optics strain sensor are done.

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Language：Japanese   Publisher：Kansai University  

Before construction of any structures on surface or subsurface of alluvial clay layer, the cement mixing method is used frequently to construct a thin improved layer at certain depth of ground. However, the effective confirmation of improved thin layer is performed by only boring and laboratory testing. In the present paper, the confirmation method of an improved thin layer by using S-wave reflection method are discussed. Especially, prospecting before and after ground improvement by S-wave reflection method, it is tried to develop the monitoring system of improved thin layer. This monitoring system is found to be applicable to construction sites.Key words: reflection method, monitoring, S wave improvement, thin improved layer

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ABSTRACT: We carried out the experimental study in order to investigate the influence of the surface roughness of rock joints on the shear strength of those. We made some artificial plaster specimens which have three different types of surface profiles, I.e. regular triangular profiles, irregular triangular profile and JRC profiles. All of these specimens are applied on the direct shear test. On the other hand, before direct shear test, in order to investigate the method of quantitative estimation of quantitative estimation of irregular joint profile, the measurement and the analysis of joint profile for each specimen using laser profilometer have conducted. As the results, we proposed the shear strength criteria which expressed by the power function, and it is recognized that this criteria is applied to various rock joints.

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ABSTRACT: The effects of the structural anisotropy on the deformation properties of granite under cyclic loading have not been clarified. In this paper, four types of granite specimens are prepared with an angle θ of the structural anisotropic plane to the loading axis of 0., 30., 60. and 90.respectively and cyclic loading tests are performed under uniaxial compression. The stress amplitude levels used in this experiment are 0-30%, 20-50% and 40-70% of the uniaxial compression. The uniaxial compressive strength for this granite. As the results, for the stress amplitude level of 0-30%: the elastic modulus under the cyclic loading is approximately constant. However it is recognized that the increase of axial strain during the cyclic loading is loading is largest for the specimen with θ of 30., and it's value under ten thousands cyclic numbers corresponds to 1.27tunes as much as the axial strain given by 20% stress for the uniaxial compressive strength, and that it's uniaxial compressive strength after cyclic loading is lowest for the all stress amplitude conditions. Further, It is clarified that it's volumetric strain only indicates the negative value under 50% and 70% stress levels under cyclic loading.

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Language：Japanese   Publisher：Japan Society of Engineering Geology  

It is well known that the groundwater in rock slope mainly flow joint, fracture zone, fault and sidcontinuty plane. In this paper, using Dipole-Dipole electric method, the electric resistivities are continuously measured in a rock slope during five rain fall patterns with the measuring line crissubg a fracture zone, and the relationship between the change of apparent electric resistively and the rain fall are discussed. As the results, making a comparison between fracture cones and the other rock mass, the characteristics of the change of apparent electric resistivity is quite different, and the other rock ass, the relationship between the change of apparent electric resistibility and rain fall can be approximated with an exponential function.Key words : rock slope, fracture zone, apparent electric resistively, continuos measurement

DOI： 10.5110/jjseg.38.74

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Other Link： http://hdl.handle.net/10112/2193

As is known, Ladanyi's shear strength criterion is only applied to the regular triangular joints. The purpose of this study is the proposal of a new shear strength criterion which is applied to irregular joints. First of all, the appropriate estimation method of irregular joint profiles must be quantitatively estimated. The artificial plaster specimens which have four different JRC profiles, and the sandstone specimens including the irregular joint are applied on the direct shear test. The other hand, before direct shear test, in order to estimate the irregular joint surface profile of those specimens, the measurement and analysis of joint surface profile for each specimen using laser profilometer have conducted. As the results, the new experimental equations which exactly represent the shear strength parameters included in Ladanyi's shear strength criterion was proposed, and it is recognized that this new experimental equations can be applied for the rock specimens having the irregular joint.KEYWORDSDiscontinuities, Failure, Joints, Laboratory Tests, Shear Strength, Statistical Analysis

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Language：Japanese  

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Other Link： http://dl.ndl.go.jp/info:ndljp/pid/10439610

We carried out the experimental study in order to investigate the influence of the surface roughness of rock joints on the shear strength of those. We made some artificial plaster specimens which have three different types of surface profiles, I.e.regular triangular profile, irregular triangular profile and JRC profiles. Al of those specimens are applied on the direct shear test. On the other hand, before directshear test, in order to investigate the method of quantitative estimation of irregular joint profile, the measurement and the analysis of joint profile for each specimen using laser profilometer have conducted. As the results, we proposed the shear strength criteria which is expressed by the power function, and it is recognized that this criteria is applied to various rock joints..Key Words : rock joint , shear strength, JRC, surface roughness, failure criteria, direct shear test.

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The electromagnetic system has been applied to search for small jacking pipe. This system consists of an oscillation coil set up on the top of a jacking pipe anda detection coil on the ground surface. The authors have already shown the following: in the case of a horizontal jacking pipe, it is possible to locate the top of the jacking pipe and determine it's depth.When the jacking pipe is inclined, it is very important that the inclination of the jacking pipe can be accurately measured during construction work. In this paper, the analytical solutions of the magnetic field produced by an inclined circular oscillation coil are presented, and basic experiments related to prospecting for inclined jacking pipe by the electromagnetic method are carried out. As a result of these experiments, it is clear that the inclination of jacking pipe can be measured by this prospecting method included the proposed corrective method of measuring value.Key words: electromagnetic method, small jacking pipe, inclination.

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Minamiyamasiro district at Kyoto prefecture is located in the southern part of Kyoto basin. The groundwater in this basin has been used water service, agriculture and industry. We have study about the groundwater resources in Minamiyamashiro district, especially, we investigated agriculture, industry and water service wells respectively in 1983 and 1993 using the hearing inquiry method, and tried to grasp the pumping and the use conditions of groundwater in this area. In this paper, as compared with these data getting by the hearing inquiry in 1983 and 1993, the changing on the actual using conditions of groundwater and on the quantity of the pumping groundwater for ten years in this area are discussed. As the results, it is recognized that the total pumping quantity of the groundwater increase about 10,000,000 ton for ten years, and that the increase of pumping for water services are marked.Key words: Minamiyamashiro district, hearing inquiry method, pumping quantity

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The shear behaviour of rock mass depends on the mechanical properties of discontinuity, and these are listed on aperture, strength, weathering, roughness, etc. Especially, it is known that the roughness of discontinuity surface directly affects shear strength of rock mass, however, the relationship between shear behaviour and roughness of discontinuity surface is not completely clear. In this paper, the roughness of discontinuity surface is measured by the laser displacement meter. Using these date, the roughness of discontinuity surface are statistically analyzed, and we are done the direct shear test. As the result, it is recognized that the analytical initial dilation angle obtained by the statistical method are corresponded with the dilation angle obtained by direct shear test under lower normal stress condition.

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ON this paper, we have tried to apply Ladanyi's shear strength criteria to irregular joints, which is only applicable for regular joints. The measurement and analysis of joint profiles have conducted to estimate quantitative processing of irregular joint roughness, and direct shear tests on plaster-sand specimens which have JRC profiles given by Barton, and coerce grain sandstone have been done. As the results, we proposed experimental equations which exactly represent the shear strength parameters included in Ladanyi's shear strength criteria, and it becomes also applicable for irregular joints rearranging the shear strength parameters by substituting the experimental equations proposed by authors.

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Language：Japanese  

It becomes very freqent to employ the jacking method for construction of lifeline. Especially, in the case of small diameterpipe, it is very important problem to locate the top of Jacking pipe under operation. The erectromagnetic method deems to be the most suitable method for such purpose. To improve the ability of prospecting, it is desirable to use the primary magnetic field basically than the secondary field. In the present paper, we introduce the acalytical solutions of the magnetic field induced by the circular oscillationcoil and describe theoretical and ezperimental results regarding the ability of an electromagnetic method to loate the top jacking pipe with the results of calculation.Key words: electromagnetic method, magnetic field, small jacking pipe

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Other Link： http://hdl.handle.net/10112/2157

J-GLOBAL

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In the determination of the shear strength of rocks, a lot of similar specimens are needed to obtain satisfactory results, but the preparation of the specimens of same characters invoices great difficulties, especially in the case of discontinuous rocks, It is desirable if the strength envelopes could be obtained from only one specimen. In this study, we carried out two types of CFS tests, and a series of constant stress shear tests for plaster specimens with regular triangular joint. In addition to these tests, we carried out multi-stage shear tests for rock specimens with artificially generated irregular joint. We made comparison of the results obtained by these tests, and examined the applicability of CFS tests.KEYWORDS: Continuous Failure State Test, Discontinuous Rock, Failure Line, Shear Strength

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This paper deals with the influence of joint roughness on the dilation behavior and the shear strength properties. Direct shear tests on seven types of plaster-sand specimens which have the rough discontinuities of regular triangle shapes have been conducted, and the comparison those results with Ladanyi and Archambault's criteria and Patton's criteria was carried out.The results obtained are summarized as follows :(1) The dilation behavior is remarkably affected by the angle of the teeth.(2) The shear strength of regular triangular joints gradually approaches the shear strength of flat joints rather than intact specimens.

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Language：Japanese  

Before the underground structures such as tunnels and large caverns will be constructed, seismic prospecting and electrical prospecting for geological surveys are often executed. However, it is few that the velocity of elastic wave and the electric resistivity obtained from these prospecting methods are directly used to the design. In this paper, the relations among electric resistivity, porosity and degree of saturation of various rock specimens were investigated by laboratory tests were compared with the field measurement data obtained by electric prospecting. As a result, it is clarified that the characterization of electric resistivity of some rock cores can be applied on the estimation of in-situ rock mass.

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Language：Japanese  

P-wave velocity of anisotropic rock specimens in the axial direction was measured under biaxial stress loading. The rock specimens are cut out from the block of Yoshino chlorite schist into the column with the angle between the plane of schistosity and the horizontal plane perpendicular to the axis of the core about 0(S0), 20(S20), 45(S45), 70(S70) and 90(S90). The relationship between P-wave velocity and directions of schistosity has been investigated under various confining pressure. The results obtained are as follows.1) It is recognized that P-wave velocity of rock specimen in the direction parallel to the axis of maximum principal stress is affected by the angle between the plane of schistosity and the horizontal plane.2) The relation between P-wave velocity and the deviator stress is expressed in terms of a hyperbolic function.3) Two constant values defined in a hyperbolic function relate with the initial elastic modulus, confining pressure and P-wave velocity of the rock specimens under the atmospheric pressure.

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Other Link： http://hdl.handle.net/10112/2158

Language：Japanese   Publisher：Japan Society of Civil Engineers  

The new method of measuring settlement using one bore hole which has enable the increase of measuring points during observation were developed. The principle of this method is based on two unique points, one of which is application of a permanent magnet as an indicator of settlement, and the other is the explotation of semi-conductor magnero resistance elements for detecting the magnetic fields. In advance of the observation, the magnets are forced into the earth penetrating the VINYL CHLORIDE casing of bore hole by the oil jack at suitable depths and intervals, and the small sized magneto-resistanve element is much use of realization of this idea. In this paper, the principles of this method, measuring procedure, the special characteristics and potential of this system and the results of field trials are desctibed.Keywords: measuring settlement system, magneto-resistance elements, permanent magnet

DOI： 10.2208/jscej.1989.409_57

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It is known that the propagation velocities of elastic waves through rocks under compressive stress conditions increase as compared with stress free conditions. Some papers has been reported on the characteristics of velocity variation under axial-stress conditions or under static-water pressure. It seems that some essential different tendencies of P-wave variations between the above stress conditions and the biaxial-stress conditions. We remodeled the pressure cell of triaxial-compression testing machine capable of measuring characters of velocity by means of super-sonic wave, and carried out a series of experiments to examine the characters of velocity change under biaxial-stress conditions. The rock specimens tested are of sandstone, granite, graphite-schist and marble as are typical ones of structures and origins of rocks.The mode of velocity change under the biaxial stresses coincides with that of strain, therefore the relation between velocity and dilation shows the linearer figure than the curve of velocity vs. stress. The increase of velocities ranges from a few percent to 50 percent. The initial velocity under free stress and the gradient of increasing velocity are considered to be related with the rock structure and the composition.

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Language：Japanese  

CiNii Books

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Other Link： http://dl.ndl.go.jp/info:ndljp/pid/10448690

When the artificial vibration is added to the soil layer, the skeleton of the soil structure is destroyed and rearranged for the state of higher density. This is the principle of the dynamic compaction methods which have been used for the improvement of foundation. The authors propose that the blasting in the soil layer as the source of energy may be more effective than the mechanical vibration from the surface. In this paper, the mechanism of soil blasting and the strength of soil are described and the results of two field experiments are discussed comparing with the theoretical considerations.As the results, it is recognized that the instant subsidence caused by the soil blasting corresponds to the several years amount of the natural subsidence.

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Language：Japanese  

CiNii Books

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Publisher：日本放送出版協会（NHK出版）  

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Publisher：日本放送出版協会（NHK出版）  

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Language：Japanese   Publisher：関西大学  

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Language：Japanese   Publisher：関西大学工業技術研究所  

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Language：Japanese   Publisher：関西大学工業技術研究所  

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Language：Japanese  

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J-GLOBAL

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Language：Japanese  

CiNii Books

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Other Link： http://dl.ndl.go.jp/info:ndljp/pid/10431784

Language：Japanese   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Country：Japan  

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Language：Japanese   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

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Language：Japanese  

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Language：Japanese  

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Venue：web  

京都盆地は地下水が豊富で 古来より地下水利用が盛んな地域である 本研究は 酒造 に地下水を利用している 酒蔵会社が密集 している京都市伏見区を対象として 地下水利 用に伴う深井戸・浅井戸観測井水位の将来予測手法として機械学習の適用を試み 予測値と実測値との 比較検討を行った.

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Venue：web  

New Austrian Tunneling Method NATM工法 で建設された 山岳トンネル において，地山の工学的な性質によって分類され，その 判定に応じて地山 を安定化させるための 支保パターンを設定している． 現在の技術では，トンネル地山等級判定は熟練した技術者によってトンネル切羽面 の岩盤強度や不連続を 観察し，9項目を 4段階で点数付けを行われている．しかし， 技術者の経験に基づく岩盤判定に対する基準の個人差が生じ ，統一的かつ標準的法とはいえない．また，少子高齢化による人手不足や 建設現場における安全向上のため，近年，さまざまな社会インフラの各段階で人工知 能が導入されている． そこで，本研究では，機械学習（サポートベクターマシン）を導入することにより， 切羽面の岩盤を評価する手法について検討を行った。

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Venue：web  

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Venue：大阪府吹田市  

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Venue：web  

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Venue：京都市  

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Venue：Osaka, Japan  

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Venue：Osaka, Japan  

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Venue：オンライン  

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Venue：大阪府吹田市  

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Venue：山口大学  

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Venue：Centro Cultural Vila FlorAvenida D. Afonso Henriques, 7014810-431 Guimarães  

NATM(New Austrian Tunnelig Method) known as sequential excavation method, is a construction method of mountain tunnels. Support patterns by NATM in Japan are designed by experienced experts regarding an overall evaluation based on the condition of a cutting face, the condition of an underground surface, compressive strength, weathering, condition joints, joins set, joint spacing, orientation of joint spring water and deterioration due to water. however, current decision methods on support patterns require expertise, and moreover, there often exists discrepancy in judements. Therefore, in this research, we try to build expert systems on design of support patterns in tunnel construction using support vector machines (SVM) which is a kind of statistical machine learning. SVM has been widely applied to various pattern classification and regression problems and recognized to be powerful learning methhod. We will also show through some real data that the proposed expert systems using SVM can suggest reasonable and objective design of tunnel support patterns.

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Venue：香川県香川大学幸町キャンパス  

水源揚水井の取水能力を数値化した健全度の不規則な時間劣化を記述する確率モデルを構築し，点検・洗浄に要するコストと取水能力の喪失に伴う損失コストの総和の期待値を最小化するという指針の下，最適な洗浄保守計画を定式化する．次に確率制御理論を適用して最適な保守計画を与える方程式を導き，数値解析を通じて最適洗浄保守計画の解析を行う．

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Venue：香川県香川大学幸町キャンパス  

平成30年7月5日～7日にかけて発生した平成30年7月豪雨により、日本各地で斜面崩壊が頻発した。本研究では、樹木を伐採せず施工可能なロックボルト・ロープネット斜面安定工法の敷設が行われている斜面とされていない斜面が混在する道路斜面を対象として、土壌雨量指数の変化とスネーク曲線の変化に基づき、本工法の表層崩壊への適用性について検討した。 対象地域において、平成30年7月5日～7日にかけての土壌雨量指数とスネーク曲線から、対象地域は、斜面崩壊の危険性があり、実際に斜面崩壊が発生した。しかし、本工法を施工している斜面は崩壊しなかったことから本工法は、大きな豪雨においても十分機能することが認められた。

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Venue：香川県香川大学幸町キャンパス  

福井県大野市（大野盆地）が本研究の対象地域である。大野盆地は地下水に恵まれており、この地下水は、大野市民が生活を送る上で欠かすことのできないものである。しかし、未だにこの地下水賦存量は把握されておらず、この先数十、数百年と利用し続けていくためには、地下水賦存量を推定する必要がある。本研究では、重力探査による解析結果を用いて、帯水層の構造を3次元でモデル化し、地下水賦存量の推定を行う。その結果、大野盆地の地下水賦存量は36.57億m³と推定され、琵琶湖の水量に対し、概ね13.3％の値であることが判明した。

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Venue：香川県香川大学幸町キャンパス  

NATM工法によるトンネル建設現場では，切羽面の岩盤評価による適切な支保パターンの決定が重要になる．現在において，岩盤評価は熟練した技術者により行われている．そこで本研究は，岩盤評価のデータを基にサポートベクターマシンという機械学習を適用し，サポートベクターマシンによる支保パターン決定の有用性を検証する．本研究は機械学習による学習の精度を検証した結果であるが，現時点で80％以上の正判別率を得ることができた．これは，目視など点検者の技術や経験によって結果にばらつきが生じる評価点データに対して高い精度であると言える．したがって，岩盤評価において，機械学習を適用することに有用性はあると結論付ける．

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Venue：大阪大学吹田キャンパス  

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Venue：大阪府吹田市  

平成29年7月の九州北部豪雨では，記録的な集中豪雨により多くの斜面が崩壊し，甚大な土砂災害ならびに流木被害が発生した。その被災地域である福岡県朝倉市松末小学校の隣接斜面においてロープネットとロックボルトを用いたユニットネット斜面安定工法（以下，「本工法」）が施工されていた（写真-1）。本報告では，主として本工法が施工された斜面周辺の調査を実施し，ゲリラ豪雨に対する本工法の抑止効果，及び有効性について検討した．

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Venue：東京都  

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Venue：大阪府吹田市  

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Venue：大阪府吹田市  

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Venue：Bangkok ,Thailand  

Kyoto basin abounds good quality groundwater whose quantity is estimated 21.1 billion tons. At Minami-yamashiro region, this good quality groundwater is pumped up as a head of a waterworks. In order to pump groundwater, it is necessary to use the well. When we use it for many years, the pumping capacity of the well is reduced, eventually it falls into malfuction. Current state of maintenance is washing of well and interval of the maintenance is determined based on an exper's empirical rules. Therefore, a management system for quantitative maintenance is not established yet. In particular, it is a problem that the performance assessment method for a well is not established. Accordingly, based on the past pumping date, we examine the performance assessment for wells in the region and then we propose prediction models for a well performance assessment for wells in the region and then we propose prediction models for a well performance with time. Moreover, in order to build the strategic and rational maintenance plan of the well, we apply the economic analysis method.

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Venue：Bangkok ,Thailand  

Heavy rain and intimidating typhoon often cause slope failure and debris flow in Japan and other Asian areas. Numerical solutions have been reported by using FEM in coupling behavior of solid and water. Typical example is a consolidation problem in which water is squeezed from soil skeleton by external load. However, these processes could not be solved by conventional FEM. This paper deals with coupling between solid and fluid in discontinuous rock and soil mass, especially rock and water mixed debris flow. This study presents a new approach in which rock block movement is solved by DDA (Discontinuous Deformation Analysis) and water movement inside the rock mass is solved by MPS (Moving Particle Simulation) method separately. Then they are coupled in the calculation to account for the mutual interaction. To analyze the coupling between the water flow and the falling blocks of rock, this study introduces the equivalent external forces for the falling blocks of rock caused by the water flow. The velocities are calculated for the fluid flow based on MPS. MPS analyzes the part of fluid alone and DDA analyzes the part of solid alone to set the initial state of the analysis. After the results is superimposed, the coupling analysis is carried out.

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Venue：兵庫県 神戸市  

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Venue：Bangkok ,Thailand  

Kyoto basin abounds good quality groundwater whose quantity is estimated 21.1 billion tons. The amount of groundwater is comparable to the Lake Biwa. At Joyo City and Yawata City that belong to Minami-yamashiro region, this good quality groundwater is pumped up as a head of a waterworks. Usually, when a well is used for many years, a clog will occur on a strainer in an aquifer and the performance of a well degrades. However, to bore a new well requires huge cost.Therefore, current state of the countermeasures for performance degradation is washing of a well. Interval of this maintenance of washing is determined based on an expert’s empirical rules. Unfortunately, a management system for quantitative maintenance is not established yet. In particular, it is a problem that the performance assessment method for a well is not established. Accordingly, based on the past pumping data of the target region, we examine the performance assessment for wells in the region and then we propose prediction models for well performance with time. Moreover, in order to build the strategic and rational maintenance plan of the wells, we apply the economic analysis method.

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Venue：Bangkok ,Thailand  

Climate change may cause natural hazards of heavy rain and typhoon, then they trigger slope failure and debris flow at many slopes in Japan and other Asian areas.In the form of limit analysis with c and , water pressures are often imposed in the equation. Stability of slope is evaluated by a factor of safety for a slope with this method. However, the limit analysis cannot analyze the time-dependent process of slope failure.Usual slope stability analysis for discontinuous media such as DEM or DDA (Discontinuous Deformation analysis) only considers movement of soils and rocks and in these cases water is taken into account implicitly. However, it is known that water explicitly affect stability of rock mass. This study presents a new approach in which rock block movement is solved by DDA and water movement is solved by MPS (Moving Particle Simulation) separately. To analyze the coupling between the water flow and the falling blocks of rock, this study introduces the equivalent external forces for the blocks of rock caused by the water flow.

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In the management and usage of groundwater resource, we need to work on an accurate grasp of the current situation and to make a future vision in the region where groundwater exploitation is active. The examined region is surrounded by mountains formed by a bowl shaped depression in the Paleozoic strata and granite. The paleozoic strata basin rock is an impermeable bed upon which there is a permeable diluvium and then alluvium. It is estimated a lot of groundwater is saved. In the past research, we performed pumping simulation analysis for the pumping well of waterworks in order to consider the influence on the groundwater level by pumping quantitatively. As a result, the fluctuation of water level by many pumping wells was able to be reproduced. However, in some wells, the tendency for a groundwater level decreasing was not reproduced, despite of having fixed or stopped the pump discharge. If a pumping well continues to pump groundwater for a long time, various groundwater ! obstacles like the fall of the groundwater level or required amount of water can not be acquired and others will surface. One of the possible reasons for this is the weakening of temporal well capability which originates from a clog in a screen in many cases. In this research, we examined quantitatively the characteristics of water-decline-level of an aging well by improving a past model and performing pumping simulation analysis.

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我が国の道路は、高度経済成長期に急ピッチで整備されてきた。建設された膨大な数の法面は、現在劣化が進んでおり、これらの法面の安定性、耐久性を、効率良く把握、評価する必要がある。法面の安定性に関わる問題は、背面地山の風化や変動が大きく影響するため、物理探査を用いる方法がとられている。しかし、単独の探査では解釈に限界があり、複数の探査で評価することが望まれる。そこで、本研究では弾性波探査、表面波探査、電気探査に着目し、原位置で得られた各々のデータに自己組織化マップを適用することで、複数の探査結果の複合的評価を試みた。

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本研究の対象地域である京都府南山城地方は、良質な地下水が豊富にありその貯水量は211 億t とされ、琵琶湖の水量275 億t に匹敵する。京都府南山城地方に属する城陽市と八幡市は、上水道水源を地下水にそれぞれ約80%、約50%依存しており、地下水利用が盛んな地域である。揚水井は長期間にわたり使用し続けていると、揚水能力が低下し、最終的には機能不全状態に至る。揚水井の掘り替えには膨大なコストがかかるため、経験則に基づいて洗浄工事を行い井戸の長寿命化を図っているが、維持管理に関する定量的な検討は十分に行われていない。そこで、研究対象地域の揚水井15 本の井戸について、約30 年にわたる地下水位と揚水データや洗浄工事の記録を分析することで、揚水井の維持管理計画に関する検討を行った。

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Venue：Bangkok ,Thailand  

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Venue：Bangkok ,Thailand  

In Japan, in the high economic growth period in 1960’s, a great number of slopes were formed to construct many roads. Now, the slopes have been aging, therefore it is important to estimate the soundness of the aging slopes and maintain slopes effectually. So, in situs, we usually carry out seismic wave method, surface wave method, and electromagnetic method as geophysical prospecting method. However, we cannot comprehensively interpret the result of each geophysical prospecting in a numerical formula of the engineering now. Therefore, we take notice of self-organizing maps used widely in a field of the information processing engineering, and tried to interpret multidimensional data by integrating. In this paper, we classified the ground property by self-organizing maps. The classification result is relatively conformal with boring data. Therefore, it is recognized that it can be used to improve the interpretive accuracy of multiple geophysical prospecting. And, it can be shown that this technique is effective to estimate of the ground property of the aging slopes.

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Venue：Taiwan, Kaohsiung  

It is important to develop a method for understanding the stability and the durability of these slopes by using “geophysical prospecting method”. However, we have a limitation to interpret the data from one geophysical prospecting method. In this paper, we focus on using multiple geophysical prospecting methods. Then, we tried to evaluate the data from multiple geophysical prospecting methods by applying Self-organizing maps (SOM).

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Venue：Taiwan, Kaohsiung  

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京都市伏見地域には良質な地下水が豊富にあり，多くの酒造会社が立ち並ぶ．この地域では，酒造りに年間およそ150 万トンの地下水を揚水する程，地下水を多く利用している．しかし，無計画な地下水利用は，地盤沈下や局地的な地下水の枯渇を引き起こす恐れがある．そこで，京都市伏見地区を対象とした地下水シミュレーションモデルを構築し，このモデルを用いた地下水利用に関する検討を行った．

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我国の道路は、高度経済成長期に急ピッチで整備されてきた。建設された膨大な数の法面は、現在劣化が進んでおり、これらの法面の安定性、耐久性を、効率良く把握、評価する必要がある。法面の安定性に関わる問題は、背面地山の風化や変動が大きく影響するため、物理探査を用いる方法がとられている。しかし、単独の探査では解釈に限界があり、複数の探査で評価することが望まれる。そこで、本研究では弾性波探査、表面波探査、電磁探査に着目し、原位置で得られた各々のデータに自己組織化マップを適用することで、複数の探査結果の複合的評価を試みた。

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Venue：Bangkok, Thailand  

In the management and a usage of a groundwater resource, we need to work on an accurate grasp of the current situation and to make a future vision in the region where the groundwater exploitation is active. In this research, we aim at the creation of the three-dimensional geological structure model in multilayered ground and the three-dimensional seepage flow analysis of groundwater by using the model. The area in this research exist many multi-layers which are alternately stratified gravel layers and clay layers. Firstly, based on bowling log and an altitude distribution map, we grasped the topography and the geological structure of a target area. Secondly, based on boring log, we interpolated the layer thickness of every layer in a model by using the Kriging method. The outline of the three-dimensional geological structure is completed by piling them up. Thirdly, considering of the position of pumping wells and the layer thickness distribution, we divided mesh. Finally, we reproduced groundwater flow by conducting groundwater analysis, and created the figure which visualized the groundwater flow.

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Venue：Bangkok, Thailand  

Many unstable slopes exist about 1000 slope failures each year have occurred in Japan. An about 90% of the failed slope is natural slope having the tree vegetation and the failure occurred in the surface ground within 3 meters in depth. The slope failure is mainly caused from the heavy rain and small earthquake. While the failures have to be prevented, the natural environment such as trees and vegetations on the slope has to be also maintained. Therefore, the retaining structure and the shotcrete, which have to cut the trees on the slope, are not suitable from the point of view of the conservation of natural state. From this point, the rock bolt and rope net method is developed to protect the slope failure with the nature conservation. The purpose of this research is to understand the mechanism of the reinforcement effect of rock bolt setting of the method. The shear test by the model 1/10 scale is conducted. As a result, it is clarified that the rock bolt setting has a large effect on the slope behavior.

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Venue：Bangkok, Thailand  

There are many unstable slopes in mountainous and valley areas in Japan. Approximately 1000 slope failures have occurred. Approximately 90% of these were surface failures, occurring at a depth of less than 3m. In Japan, as in addition to earthquakes, extreme weather conditions such as typhoons, heavy rain and heavy snow often occur, landslides present a serious danger. Moreover, environmental problems such as global warming need to also be considered. One effective counter-measure is the preservation and growth of CO2 absorbing forests. In response to these needs, this research, presents a new method of slope stabilization which can prevent slope collapses, while also considering the environment and scenery. This method utilizes rock-bolts, rope-nets, and pressure plates as reinforcing materials, while also minimizing the need to remove trees, in order to preserve forests. This research utilizes shearing tests at a 1/10 scale, in order to clarify the effectiveness of reinforcements utilizing this method in decomposed granite soil with a modified water content. As a result, it was found that the effect of the reinforcement method contributed significantly to the behavior of each material.

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Venue：Bangkok, Thailand  

In this research, we chiefly conducted on-site measurement and analysis to examine how the pumping wells influence groundwater behavior. And, we tried to reproduce the water level decreases of the pumping well caused by well aging. First of all, we understood the influence on the fluctuation of water level by a difference in geographical feature or geology conditions, based on long-term data concerning pumping discharge and groundwater level at each pumping well in the waterworks. Next, we created the wide-ranged analytical model including all the wells for analysis. And, we created models which use the water head value acquired by the wide-ranged model as a boundary condition, and performed a simulation. Finally, we tried to reproduce the water level decreases of the pumping wells caused by well aging by using the made models. As a result, it can be seen from our research that the fluctuation of water evel caused by group wells has been reproduced accurately by using our model for this present study. And, the analysis considering the well aging was reproduced the water level decreases caused by strainer clogging.

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Venue：Bangkok, Thailand  

In Japan, in the high economic growth period in 1960’s, a great number of slopes were formed to construct many roads. Now, the slopes have been aging, it is important to estimate the health of the aging slope and maintain slopes effectually. So, in situs, we usually carry out seismic wave method, surface wave method, and electric method. However, there is not the technique to compound and interpret the result of each geophysical prospectings in a numerical formula of the engineering now. Therefore, we notice to self-organizing maps used widely in a field of the information processing engineering, and tried to interpret multidimensional data by integrating.In this paper, we classified the ground property by self-organizing maps. The classification result is relatively conformal with boring data. Therefore, it is recognized that it can be used to improve the interpretative accuracy of compound geophysical prospectings. And, it can be shown that this technique is effective to estimate of the ground property of the aging slope.

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Venue：Bangkok, Thailand  

Kyoto city has various traditional cultures and industries. One of these is the production of Japanese sake, for which Fushimi-region in Kyoto is famous. The object area, which is 4 km2 and overcrowded with 50 wells, uses groundwater. However, new sewage pipe construction was done to the area that the brewing company concentrated on last year. As purpose of this study, the influence that those underground structures exerted on the groundwater level and the influence on the groundwater pollution were examined by the numerical analysis that reflected the observational data. We had set the pump volume and selected the contaminant material that would extend most under analysis. In this, we predicted the extent of the pollution, which is being blocked by the clay layer. As a result, we concluded that continuous clay layer at this region eases the influence of pumping volume from deep layer to water's fluctuation level in the shallow layer, and prevents the invasion of contaminants.

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Venue：Penang Island  

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Venue：Penang Island  

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Venue：Penang Island  

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Venue：Penang Island  

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Venue：Penang Island  

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Venue：八戸  

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Venue：八戸  

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Venue：関西大学100周年記念会館  

京都盆地は種々な目的によって、地下水の利用が盛んな地域です。過去の研究により京都盆地の地下水賦存量を計算した結果、約211億トンとなりました。琵琶湖の貯水量が約270億トンであるので、京都盆地の地下には琵琶湖に匹敵する水量の地下水が存在していることになります。京都は平安京の時代より、地下水と深く関わってきました。今日では、日本庭園、茶道、酒造り、京友禅等、京都の伝統文化につながっていますが、ここでは京都の地下水と文化、そして水と生命について種々な面から検討を行いました。

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Recently, a lot of difficult localized torrential rains to forecast of calling a guerrilla downpour has been generated by the influence of global warming. Sediment disasters such as the mud flow, landslides have been generated by the guerrilla downpour in various places of Japan. In these natural damages, they are not only the transportation such as roads and railways but also it is current states to have done the house and the life damage. The establishment of the technique that can do the accuracy evaluation of shape and hydraulic characteristics of the discontinuity in the bedrock with the causal relation with the slope failure is hoped for. In this report, 3-D electric survey was executed before and after pouring water in the water level observation hole in the slope. The change rate of the resistivity was calculated by repeated survey. Position and strike and dip of weak parts were presumed from the change rate. Next, the saturation was presumed by applying the expression of Archie to the change rate of the electric resistivity. In addition, conversion from the electric resistivity that had been obtained because of 3-D electric survey to RQD was tried from the correlation of the resistivity and RQD. For the reasons stated above, 3-D electric survey is very useful for detail investigation for a slope.

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Shotcrete has been used to rainforce the road slopes, especially for cut slopes until 1970's in Japan. The slopes were decrepit since shotcrete slopes were constructed more than 30 years ago. Recently, the slope collapse caused by cavities existing behind the shotcrete and/or ground weathering was reported. Geophysical explorations have not been used practically to detect the cavities behind the shotcrete of the slopes so far. However, these geophysical exploration methods such as infrared thermal imaging, GPR, seismic exploration, electric and electromagnetic explorations have great potential to detect the cavities behind the shotcrete with non-destructive manners. In this paper, we applied different geophysical exploration methods to actual road slopes and observation/measuring results were compared. Obtained results from this study show that the geophysical exploration methods are effective methods to detect the cavities in the decrepit slopes. We also discussed the merit and demerit of each geophysical exploration method as well as their applicability for the decrepit slopes exploration.

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Venue：正修科技大学，台湾  

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Invited 20050330-20050401

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Venue：ソウル国立大学  

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