基于Pushover分析的群桩基础抗震性能分析方法.pdfVIP

43 2 Vol. 43 No. 2 2 0 1 0 2 CH INA CIV IL ENGINEER ING JOURNAL Feb. 2010 Pushover 1 2 叶爱君 鲁传安 ( 1. , 200092; 2. , 200070) : , Pushover, , ( ), (), ,, : ,;, : ; ; Pushover; ; ; + : U442. 5 5 : A : 1000131 (2010) A seism ic performance analysis approach base on Pushover analysis for group pile foun ations 1 2 Ye A ij un Lu Chuan an ( 1. State Key Laboratory forDisasterReduction of C ivilEngineering, TongjiUniversity, Shanghai200092, China; 2. ShanghaiTunnelEngineering RailTransit Design and Research Institute, Shanghai200070, China) Abstract: Treating a group pile foundation as one entity component, an approach of seism ic performance analysis for group pile foundations was developed, based on Pushover analysis. A load model and a nonlinear structure model ( inelastic pilemodel and nonlinear boundary condition) for group pile foundationswere established, and two specific seism ic performance indices, displacement ductility factor and resistance amplification factor, were proposed. The seism ic performance analysis of a realgroup pile foundation was conducted. Based on the nonlinear structuralmodel of the group pile foundation, a series of load caseswere developed, the corresponding Pushover curves, the displacement ductility factors, and the resistance amplification factorswere calculated. The results indicated that, the axial force and bending moment at thebottom of the pile cap slightly influenced the seism icperform ance index, while their effects on the lateral force and displacement in yield and ultmi ate lmi it statewer