考虑土骨架非线性的饱和土-结构相互作用分析  

Analysis of saturated soil-structure interaction considering soil skeleton nonlinearity

作　　者：陈少林[1] 朱学江 赵宇昕[1] 陈国兴[2] CHEN Shaolin;ZHU Xuejiang;ZHAO Yuxin;CHEN Guoxing(Department of Civil Engineerng,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China;Institute of Geotechnical Engineering,Nanjing Tech University,Nanjing 210009,China)

机构地区：[1]南京航空航天大学土木工程系,江苏南京210016 [2]南京工业大学岩土工程研究所,江苏南京210009

出　　处：《地震工程与工程振动》2019年第1期114-127,共14页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金项目(51178222;51378260)~~

摘　　要：强地震作用下,饱和土体将进入非线性,有必要考虑非线性饱和土的地震响应以及非线性饱和土-结构相互作用问题。本文采用Biot饱和多孔介质模型,基于不规则加卸载准则的修正Davidenkov模型来描述近场区域内饱和土骨架的非线性特性,并采用集中质量显式有限元方法进行分析;远场区介质假定为线弹性饱和多孔介质,通过多次透射人工边界进行模拟;结构采用Newmark隐式时步积分方法进行分析。通过自编程序实现了非线性饱和土体的地震反应分析以及非线性饱和土-基础-结构相互作用分析。通过算例,对比分析了土体非线性对饱和土体、基础和结构反应的影响。Under strong earthquakes,soil nonlinearity and pore water pressure have a great influence on the seismic response of soils.It is necessary to consider the seismic response of nonlinear saturated soils and the nonlinear saturated soil-structure interaction problem.In this paper,the soil is modeled by the Biot porous medium model.The Davidenkov model and the modified Masing rule is used to describe the nonlinear characteristics of the saturated soil skeleton in the near-field region which is analyzed by the lumped-mass explicit finite element method.Far-field region is assumed to be saturated poroelastic media,which is simulated by transmitting artificial boundaries.The structure is analyzed by Newmark implicit time integral method.The foundation is assumed to be rigid and the explicit time integral scheme is used to solve it.The corresponding code is programmed.Numerical examples for three-dimensional analysis of saturated half space and saturated soil-foudation-frame structure system under earthquake are presented.The linear elastic and nonlinear saturated soils are considered respectively and the influence of nonlinearity on the response of saturated soil,foundation and structure is analyzed through comparison between the results of linear elastic case and nonlinear case.

关 键 词：土-结构动力相互作用 饱和多孔介质 非线性动力反应 Davidenkov模型 透射边界 

分 类 号：TU435[建筑科学—岩土工程]