可液化地基群桩基础地震反应总应力与有效应力分析的比较  

Comparison Study of Total Stress and Effective Stress Analyses for Seismic Response of Pile Group Foundation in Liquefiable Soil

作　　者：戴琰 陈国兴[1,2] 王志华 DAI Yan;CHEN Guoxing;WANG Zhihua(Institute of Geotechnical Engineering, Nanjing Tech University, Nanjing 210009,China;Civil Engineering＆ Earthquake Disaster Prevention Center of Jiangsu Province,Nanjing 210009,China)

机构地区：[1]南京工业大学岩土工程研究所,江苏南京210009 [2]江苏省土木工程防震技术研究中心,江苏南京210009

出　　处：《防灾减灾工程学报》2017年第5期795-801,共7页Journal of Disaster Prevention and Mitigation Engineering

基　　金：交通运输部西部交通建设科技项目(2009318225100)资助

摘　　要：可液化土体动力特性的描述方法可能对群桩基础动力反应产生显著的影响。基于Davidenkov本构模型和Byrne改进的增量孔压模型,对比分析了总应力法和有效应力法计算的可液化地基中群桩基础地震反应特性。结果表明,群桩外侧地基最易液化,自由场地基次之,群桩内地基土最不易液化;与总应力法的计算结果相比,有效应力法计算得到的地表加速度反应谱谱值的短周期过滤和长周期放大效应更加显著,卓越周期向长周期方向移动;同时,有效应力法计算得到的桩身弯矩也有所增大。Seismic responses of pile group may be varies significantly when adopting different constitutive models to describe the liquefiable soils.Based on the modified Davidenkov constitutive model and the strain-based Byrne pore pressure increment model,comparison of total stress and effective stress analysis for seismic responses of the pile group foundation in liquefiable soil was performed.The results show that soil outside the pile group is higher liquefaction potential,soil in free field is low liquefaction potential,and soil within the pile group is lowest liquefaction potential.Compared with the results of total stress analyses,the surface acceleration response spectra of effective stress analyses presents the characteristics of low frequency amplification and high frequency wave-filtering,and the predominant periods of spectra move toward long periods;in addition,the bending moments of the piles along the depth are slightly larger.

关 键 词：群桩基础 可液化场地 地震反应 总应力法 有效应力法 

分 类 号：TU435[建筑科学—岩土工程]