基于应变梯度非局部Biot理论的饱和土地基动力特性研究  

Dynamic characteristics of saturated soil foundations based on the strain gradient nonlocal Biot theory

作　　者：黄志刚 徐志华 丁海滨[3,4] 童立红 徐长节[3,4] 雷祖祥 HUANG Zhigang;XU Zhihua;DING Haibin;TONG Lihong;XU Changjie;LEI Zuxiang(Jiangxi Transportation Engineering Group Co.,Ltd.,Nanchang 330028,Jiangxi,China;Jiangxi Intelligent Bridge Maintenance Engineering Technology Research Center,Nanchang 330028,Jiangxi,China;State Key Laboratory of Performance Monitoring and Protecting of Rail Transit Infrastructure,East China Jiaotong University,Nanchang 330013,Jiangxi,China;Jiangxi Key Laboratory of Infrastructure Safety Control in Geotechnical Engineering,East China Jiaotong University,Nanchang 330013,Jiangxi,China)

机构地区：[1]江西交通工程集团有限公司,江西南昌330028 [2]江西省桥梁智能养护工程技术研究中心,江西南昌330028 [3]华东交通大学轨道交通基础设施性能监测与保障国家重点实验室,江西南昌330013 [4]华东交通大学江西省岩土工程基础设施安全与控制重点实验室,江西南昌330013

出　　处：《地震工程学报》2024年第2期325-334,共10页China Earthquake Engineering Journal

基　　金：江西省交通运输厅科技项目(2021H0004);国家自然科学基金(52208344);国家自然科学基金-高铁联合基金(U1934208);江西省自然科学基金(20224BAB214068)。

摘　　要：为探究孔隙尺寸效应(非局部参数表征)和介质局部非均匀效应(尺寸因子表征)对饱和土地基动力响应的影响,基于应变梯度非局部Biot理论,采用无网格法编制循环荷载下饱和土地基动力响应计算程序,验证无网格法程序的正确性。结果表明,尺寸因子为定值时,随着非局部参数的增加,观测点位移及孔压起始响应的时间有所延迟;而非局部参数为定值时,随尺寸因子的增加,观测点位移及孔压起始响应时间有所提前;说明考虑孔隙尺寸效应会减小系统的宏观模量,而考虑土体结构的非均匀效应则会增加系统的宏观模量。研究提出采用无网格法求解饱和土动力问题的方法和思路,可为今后研究饱和土动力学问题的研究提供借鉴。This paper explores the influences of the pore size effect(represented by a nonlocal parameter)and the heterogeneous effect of the medium(represented by a size factor)on the dynamic response of saturated soil foundations.Based on the strain gradient nonlocal Biot theory,the calculation program for the dynamic response of a saturated soil foundation subjected to cyclic load was compiled using the meshless method.Therefore,the accuracy of the meshless method program was verified.Results indicate that the responses of displacement and pore pressure at observation points are delayed with the increase in nonlocal parameters,maintaining the scale factor as constant.By contrast,the responses are advanced with the increase in the scale factor,maintaining the nonlocal parameter as constant.This finding indicates that the macro-modulus of the system will be decreased considering the pore size effect,which will be increased considering the heterogeneous effect of soil structures.Methods and ideas for solving dynamic problems of saturated soil using the proposed meshless method in this paper could provide references for future research on similar problems.

关 键 词：应变梯度 非局部Biot理论 无网格法 饱和土地基 动力特性 

分 类 号：TU435[建筑科学—岩土工程]