基于粒子群优化算法的软土场地Davidenkov模型参数拟合与应用  

Parametric fitting of soft soil sites’ Davidenkov model based on PSO algorithm and its application

作　　者：王沿朝 陈清军[1] WANG Yanchao;CHEN Qingjun(State Key Lab of Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学土木工程防灾国家重点实验室

出　　处：《振动与冲击》2019年第17期8-16,共9页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(51778489);国家科技支撑计划课题(2015BAK17B04)

摘　　要：为探究Davidenkov模型在软土场地地震反应分析中的应用,推导了Davidenkov模型的非线性动力本构模型在初始加载、卸载和再加载阶段的增量剪切模量表达式,并将土体动应力-应变关系推广到三维。基于粒子群优化算法对Davidenkov模型的参数进行拟合,利用MATLAB编制了拟合程序,通过对典型砂土和黏土试验数据进行拟合并验证了方法的适用性,同时对某典型上海软土场地的参数进行了拟合。在此基础上,利用ABAQUS软件提供的二次开发平台UMAT,编制了基于Davidenkov模型的土体非线性动力本构模型计算子程序,利用复杂加载路径验证了该子程序的正确性,实现了在ABAQUS软件中软土非线性动力本构模型的二次开发。最后,以某典型上海软土场地为例,对比分析了上海软土场地基于非线性动力本构模型的计算结果和等效线性化的结果。结果表明:粒子群优化算法能很好地对Davidenkov模型的参数进行拟合;该非线性动力本构模型计算子程序能够较好地描述软土场地的动力非线性行为;在该算例中,上海软土场地基于非线性动力本构模型的加速度响应值和相对位移响应值要小于等效线性化的计算结果。Here,to explore applications of Davidenkov model in seismic response analysis of soft soil sites,the incremental shear modulus expressions for Davidenkov model’s nonlinear dynamic constitutive model in initial loading,unloading and reloading stages were derived,and the soil body’s dynamic stress-strain relationship was extended to 3-D.Then,parameters of Davidenkov model were fitted using the particle swarm optimization(PSO)algorithm and the fitting program was compiled with MATLAB.The applicability of the method was verified through fitting test data of typical sand and clay.Parameters of a certain typical Shanghai soft soil site were fitted.Afterward,using the secondary development platform UMAT provided with ABAQUS,the subroutine for the nonlinear dynamic constitutive model of soft soil body based on Davidenkov model was compiled,and the correctness of the subroutine was verified through a complex loading path.Finally,taking a certain typical Shanghai soft soil site as an example,the calculation results based on the nonlinear dynamic constitutive model and those using the equivalent linearization method were contrastively analyzed.The results showed that parameters of Davidenkov model can be well fitted with the PSO algorithm;the subroutine of the nonlinear dynamic constitutive model proposed here can better describe nonlinear behaviors of soft soil sites;acceleration response values and relative displacement response ones of the typical Shanghai soft soil site based on the nonlinear dynamic constitutive model are smaller than those using the equivalent linearization method.

关 键 词：软土场地 非线性动力本构模型 粒子群优化算法 ABAQUS软件 二次开发 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3