報告書番号

381020

タイトル（和文）

フィルダムの動的解析に基づくすべり安定評価手法の－考察

タイトル（英文）

A CONSIDERATION ON THE METHOD OF EVALUATION FOR SLIDING STABILITY OF FILL DAMS DURING STRONG MOTION EARTHQUAKES BASED UPON DYNAMIC ANALYSIS

概要 （図表や脚注は「報告書全文」に掲載しております）

フィルダムの動的安定解析は入力地震動，物性，解析手法，すべり安定評価手法の４項目から成り立つと考えられるが，このうち第４の項目については，他の項目と比べた場合末解明な事項が多い。本報告ではフィルダムの地震時安定評価の手順を示し，すべり安定評価手法に関してすべり土塊の“等価瞬間震度”の概念を導入し，等価瞬間震度とすべり安全率との対応関係を見出した。また，円弧すべり線上土塊の等価瞬間震度に対応する慣性力，重力，すべり線上の応力の釣り合い式から，土塊がすべり出するのに必要な“降状震度”を誘導し，安全率が１を下回るすべり円弧に対し，すべり線上土塊の残留変形量を計算し安定評価を行う動的解析に基づく新しい耐震設計手法を提示した。

概要 （英文）

THE DYNAMIC ANALYSIS IS A COMPOSITE SYSTEM CONSISTING OF DESIGN EARTHQUAKE MOTION, DYNAMIC MATERIAL PROPERTIES, ANALYTICAL METHOD AND THE METHOD OF EVALUATION FOR SLIDING STABILITY, AND THE DETAIL OF EACH ITEM MUST BE ESTABLISHED,THE FOURTH ITEM, HOWEVER ISNOT ESTABLISHED SUFFICIENTLY, SO THAT THE FACT MAKES A NARROW PATH FORTHE SMOOTHING IMPROVEMENT IN SEISMIC DESIGN METHOD OF THE FILL DAMS.THIS PAPER IS WRITTEN, IN ORDER TO BREAK ABOVE MENTIONED DEAD ROCK, INTENDING TO PROPOSE A METHOD OF EVALUATION FOR THE SLIDING STABILITY OF FILL DAMS DURING STRONG MOTION EARTHQUAKES BASED ON THE DYNAMIC ANALYSIS, DEVELOPING THE METHOD CONSTRUCTED SO FAR THROUGHOUT MANY CASE STUDIES AND MODEL TESTS.IN THIS ANALYSIS RESIDUAL DEFORMATION OF SIDING MASS WHICH OCCURS AS A RESULT OF EXCESS OF AVERAGE ACCELERATION OVER YIELD ACCELERATION IS CALCULATED VIA DOUBLE INTEGRAL OF DIFFERENCE OF BOTH ACCELERATIONS.WITH SOME EXAMPLES CALCULATED BASED ON ABOVE PROCEDURES, IT MAYBE SAID THAT THE SURFACE SLIDING OF ROCK FILL DAM IS SIMULATED AS A SORT OF PROGRESSIVE FAILURE.SYNTHESIZING ABOVE ALL RESULTS, THE PROCEDUREFOR EVALUATION OF THE SLIDING STABILITY OF ROCK FILL DAMS DURING STRONG MOTION EARTHQUAKES IS PRESENTED, SO THAT IT MAY BE CONSIDERED THAT A NEW METHOD FOR SEISMIC DESIGN OF FILL DAMS BASED UPON DYNAMIC ANALYSIS IS PRESENTED.

報告者

キーワード