Numerical Analysis of Interaction between Soils and Pile Group Based on the Full-scale Statnamic Test

Abstract

本研究では，ソルトレーク国際空港で実施された実大群杭の静･動的載荷試験(Rollins et al. 1998, 2005)を対象として，地盤と群杭の相互作用を明らかにするため，2次元有限要素法を用い数値解析を行った。数値解析では動的な荷重だけを考慮した場合と動的載荷前の静的な荷重も考慮した場合の2種類の解析を行なった。数値解析より得られた荷重-変位関係と曲げモーメント曲線は実験結果と概ね一致した。また，準静的載荷が地盤の応力状態に及ぼす影響を明らかにするため，地盤のせん断応力-ひずみ関係を調べた。その結果，準静的な載荷過程を考慮することで解析の精度が向上することが確認された。

Numerical analysis for interaction between soil and pile group is performed using finite element method with 2D modeling. Results of numerical analysis are compared with the full-scale statnamic test of a 3 x 5 pile group conducted in the Salt Lake City International Airport site. In the numerical analysis of the pile group, there are two cases. The first case is that dynamic loads without cycle static loads. The other is that static loads prior to dynamic loads were applied at the group pile. In results, load versus deflection curves and bending moment versus depth are compared with the measured ones. Also, when numerical analysis includes the static loading before the dynamic loading (Case 2), the load-deflection curves were larger than measured ones but agree better than that of Case 1.