研究者詳細 - 柴田　俊文

Numerical simulation of embankment failure due to overflow by Moving Particle Semi-implicit method 査読

その他リンク： https://jlc.jst.go.jp/DN/JLC/20020753571?from=CiNii

T. Shuku, K. Fujisawa, S. Nishimura, T. Shibata

IDRE Journal 84 ( 1 ) I_31 - -I_38 2016年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：公益社団法人農業農村工学会

Recently, the evaluation of the failure potential of earth-filled dams has become important because of the increasing occurrence of storm rainfall. Although most instances of earth-filled dam failure are caused by overflow, in-depth knowledge of the mechanism of the erosion and failure process of embankments due to overflow is still lacking. This paper presents a numerical method for simulating an embankment erosion and failure process by the moving particle semi-implicit (MPS) method. To reasonably simulate the erosion and failure process of an embankment due to overflow, a simple erosion model whose parameters can be determined through erosion tests on embankment materials was newly incorporated into the original MPS method. An embankment erosion and failure process observed in a model test was simulated by the proposed MPS method to confirm its practicability. Although the simulation accuracy for the erosion rate is slightly low at the beginning of the erosion, the average simulated values of the erosion rate are almost the same as the experimental values. The proposed MPS method can be a useful tool in embankment design practices to simulate embankment erosion due to overflow and to discuss remedial measures against overflow.

DOI： 10.11408/jsidre.84.I_31

その他リンク： https://jlc.jst.go.jp/DN/JLC/20020753557?from=CiNii

Sensitivity analysis of earth-filled dams based on experimental design 査読

T. Shuku, S. Nishimura, T. Shibata

IDRE Journal 83 ( 4 ) II_77 - II_82 2015年

Risk Evaluation of Earth-fills Due to Severe Earthquakes and Heavy Rains 査読

S. Nishimura, T. Shibata, T. Shuku, K. Mizuma

Proceedings of Symposium on Reliability of Engineering Systems 115 - 124 2015年

Diagnosis of Earth-Fill Dams by Several Sounding Tests 査読

Shin-ichi Nishimura, Toshifumi Shibata, Takayuki Shuku

GEOTECHNICAL SAFETY AND RISK V 334 - 339 2015年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：IOS PRESS

The spatial distribution of the strength inside an earth-fill dam is identified by sounding tests. In this research, the Swedish Weight Sounding (SWS) test is employed, and the spatially high-density test is possible to identify the spatial correlation structure by the SWS. The correlation structure of an earth-fill could be identified accurately based on the sounding results, and the high resolution of the spatial distribution could be visualized by using the indicator simulation. Consequently, it has been verified the practical use of the spatial distribution of the probability that the N-value is lower than the threshold value, may be used for the maintenance of an earth-fill dam.

DOI： 10.3233/978-1-61499-580-7-334

Web of Science

Reliability-based design for earth-fill dams against heavy rains 査読

Shin-Ichi Nishimura, Takayuki Shuku, Toshifumi Shibata, Kazunori Fujisawa

15th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering, ARC 2015: New Innovations and Sustainability 2 ( 71 ) 2440 - 2444 2015年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：Asian Regional Conference on Soil Mechanics and Geotechnical Engineering

To mitigate the disasters of decrepit earth-fill dams, improvement work is conducted. Since there is a recent demand for low-cost improvements, the development of a design method for optimum improvement work at a low cost is the final objective of this research. The reliability-based design approach is discussed as such a design method. Heavy rains are the most serious events for aged fill-dams, and sometimes overflows leading to breaching occur. From the estimated probability of overflow, the probability of submergence in the downstream is estimated for the reliability-based design. The remarkable point in this paper is that the probability of occurrences of heavy rains and the uncertainty of the soil properties are simultaneously considered for the design. Considering the disaster loss, the risk of submergence could be assessed.

DOI： 10.3208/jgssp.JPN-044

Scopus

An eco-friendly design method for geotechnical structures based on LCC 査読

T. Shuku, S. Nishimura, Y. Shimokado, T. Shibata

LIFE-CYCLE OF STRUCTURAL SYSTEMS: DESIGN, ASSESSMENT, MAINTENANCE AND MANAGEMENT 1398 - 1404 2015年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：CRC PRESS-TAYLOR & FRANCIS GROUP

This study presents an eco-friendly design method for infrastructures based on contingent valuation method (CVM). First, a questionnaire survey based on the CVM was conducted to estimate monetary values of stream habitat which can be damaged by river improvement works such as flood prevention works. Second, a design method which can quantitatively evaluate impacts on stream habitat due to flood prevention works was proposed by combining computation of non-uniform flow with a method of stream habitat estimation called physical habitat simulation model (PHABSIM). Finally, monetary value of environmental loss due to flood prevention works was estimated by using results of CVM, and the effectiveness of the eco-friendly design method was discussed through a numerical example.

Web of Science

応答曲面法によるため池破堤時の被害額の簡易推定査読

Diagnosis of earth-fill dams by synthesized approach of sounding and surface wave method 査読

S. Nishimura, T. Shibata, T. Shuku

Proceedings of the 12th International Conference on Applications of Statistics and Probability in Civil Engineering 64 - 70 2015年

豪雨時の越流破堤に対するため池堤体の信頼性設計

西村伸一, 珠玖隆行, 柴田俊文, 藤澤和謙

地盤工学会誌 63 ( 5 ) 30 - 31 2015年

ため池破堤による想定リスクの簡易評価手法査読

水間啓慈, 西村伸一, 柴田俊文, 珠玖隆行

構造物の安全性および信頼性Vol.8（JCOSSAR2015）論文集 475 - 481 2015年

水間啓慈, 西村伸一, 柴田俊文, 珠玖隆行

農業農村工学会論文集 299 ( 5 ) I_147 - I_153 2015年

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：The Japanese Society of Irrigation, Drainage and Rural Engineering

我が国には江戸期以前に築造されたものも含め農業用ため池が数多く存在し, 地震や豪雨のリスクに常に直面している．このため, 遅滞なく効率的に改修等のハード対策や管理体制の強化等のソフト対策を講ずる必要があり, 破堤時の想定被害額を考慮しながら優先順位を決定し計画的に対応を図ることが求められている．しかしながら, 既定の氾濫解析に基づく被害額算定手法は複雑であり, 優先度を検討する数多くのため池の被害額を一度に算定することは難しいことから, 容易に被害額を推定できる簡略化された手法が必要となる．本研究では, このような課題に対応するため, 応答曲面法を用いて被害額を簡易に推定する手法を提案する．応答曲面法とは, 実験計画法に基づく回帰分析により, 因子と応答との定量的な関係を表現する回帰式を作成する手法であり, 得られた回帰式は応答曲面と呼ばれる．被害額算定に考慮すべき多くの因子について感度解析を行い, 被害額の値に大きく寄与する4つの因子を抽出した．これらの因子を用いて作成した応答曲面の決定係数R²は0.84と高く, 行政機関等が行う被害額の簡易推定への実用の可能性が示唆される結果が得られた．

DOI： 10.11408/jsidre.83.I_147

その他リンク： https://jlc.jst.go.jp/DN/JLC/20015919326?from=CiNii

ため池破堤による想定被害額の簡易な比較手法査読

水間啓慈, 西村伸一, 柴田俊文, 珠玖隆行

農業農村工学会論文集 295 ( 1 ) 39 - 46 2015年

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：公益社団法人農業農村工学会

地震や集中豪雨による農業用ため池の決壊は，下流域に大きな洪水を発生させ，農業水利施設の中で最も甚大な被害を生じさせる事象の一つである．このため，土地改良施設のリスクを評価しその機能を保全しようとする際に，ため池が決壊した場合の被害額を事前に想定することは非常に重要となる．一方，国が定める被害額算定手法は複雑であり，様々な資産データの収集・整理に多大な労力や時間を必要とする．そこで本研究では，ため池が決壊した場合の氾濫域における被害額を算定する簡易な手法を提案する．提案する手法は，対策を講ずる地区の選定時等に実際に適用できるよう容易に入手可能な資産データのみを用いることとした．3池の氾濫解析結果に提案する手法を適用し被害額を算定した．その結果，規定の方法と大差無く被害額を算定できたことから，提案する手法は有用との結論が得られた．

DOI： 10.11408/jsidre.83.39

その他リンク： https://jlc.jst.go.jp/DN/JLC/20021009394?from=CiNii

Evaluation of Strength of Soft Ground Improved by Vacuum Consolidation 査読

T. Shibata, S. Nishimura, M. Fujii, A. Murakami

Geotechnical Engineering Journal of the SEAGS & AGSSEA 46 ( 1 ) 95 - 102 2015年

Prediction of the ground and dyke behavior with vacuum consolidation 査読

T. Shibata, A. Murakami, M. Fujii

Computer Methods and Recent Advances in Geomechanics 1223 - 1228 2015年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：CRC PRESS-TAYLOR & FRANCIS GROUP

The present paper addresses the prediction of the behavior of a ground and a reservoir dyke with a retaining wall at the site of a regulating reservoir whose soft soil foundation is improved by using both the usual em-bankment preloading and vacuum consolidation. To evaluate the settlement, a numerical analysis using an elasto-plastic FEM for soil-water coupled problems, incorporating the SYS Cam-clay model, is carried out, and an inverse analysis approach is adopted. The particle filter is used to identify the geomechanical parame-ters based on the measured settlement. A prediction of the surface deformation and the displacements at the crown of the precast retaining wall is performed using the identified parameters.

Web of Science