地层结构对砂土液化影响的有效应力动力分析
|
摘要
根据上海市区典型土层的力学参数,构造不同地层组合的计算剖面,利用Biot固结理论和亚塑性边界面模型的排水有效应力动力分析法,研究地层结构对砂土液化的影响。分析发现:上履土层厚度增加时,砂土峰值孔压比随之减小;上履土层较软时,砂土峰值剪应力先增加、后减小;较硬时,峰值剪应力单调增加。下卧土层越厚,砂土层的峰值孔压比越小,峰值剪应力愈大,总体变化都不大,但下卧土层较软时,砂土层的峰值孔压比变化相对明显。
Based on the meachnical behaviors of representative soil layer in Shanghai,several computation profiles with different soil layer constructions are built.An effective-stress procedure,in which the bounding surface hypoplasticity model and Biot consolidation formulation are coupled,is used to analyze the effect of soil layer constructions on liquefaction of sandy soil.The results show: the thickness of covering soil layer increases,peak pore pressure ratio of sandy soil decreases;when it is softer,shear stress of sandy soil increases firstly,then decreases;but harder,it increases continuously.The deeper underlying soil layer is,the smaller peak pore pressure ratio and the more shear stress of sandy soil is;both are not obvious.But,if softer,the peak pore pressure ratio of sandy soil changes more sharply.
Based on the meachnical behaviors of representative soil layer in Shanghai,several computation profiles with different soil layer constructions are built.An effective-stress procedure,in which the bounding surface hypoplasticity model and Biot consolidation formulation are coupled,is used to analyze the effect of soil layer constructions on liquefaction of sandy soil.The results show: the thickness of covering soil layer increases,peak pore pressure ratio of sandy soil decreases;when it is softer,shear stress of sandy soil increases firstly,then decreases;but harder,it increases continuously.The deeper underlying soil layer is,the smaller peak pore pressure ratio and the more shear stress of sandy soil is;both are not obvious.But,if softer,the peak pore pressure ratio of sandy soil changes more sharply.
引文
[1]陈国兴,胡庆兴.关于砂土液化判别的若干意见[J].地震工程与工程振动,2002,22(1):141-151.CHEN Guo-xing,HU Qing-xing.Some comments onmethodologies for estimating liquefaction of sandy soil[J].Earthauke Engineering and Engineering Vibration,2002,22(1):141-151.
[2]刘金稻,金晓媚.饱和砂土液化判别方法中问题浅[J].工程地质学报,1992,8(3):379-384.LIU Jin-tao,JIN Xiao-mei.Preliminary analysis of themethod of discrimination of sandy soil liquefaction[J].Journal of Engineering Geology,1992,8(3):379-384.
[3]薄景山,李秀领,刘红帅.土层结构对地表加速度峰值的影响[J].地震工程与工程振动,2003,23(3):35-40.BAO Jin-shan,LI Xiu-ling,LIU Hong-shuai.Effects ofsoil construction on peak acceralations of ground motion[J].Earthauke Engineering and Engineering Vibration,2003,23(3):35-40.
[4]庄迎春,谢康和,朱益军,等.地层组合对砂土液化的影响分析[J].岩土力学,2003,24(6):991-996.ZHUANG Ying-chun,XIE Kang-he,ZHU Yi-jun,et al.Analysis for influence of multi-layered soil stratum onsand liquefaction[J].Rock and Soil Mechanics,2003,24(6):991-996.
[5]Li X S.Reduced-order sand model for ground responseanalysis[J].Journal of Engineering Mechanics,1996,122(9):872-881.
[6]蔡宏英,周健.深厚覆盖软土地层多向地震动力反应分析[J].同济大学学报,2000,28(2):177-182.CAI Hong-ying,ZHOU Jian.Elasto-plastic dynamicresponse of horizontally layered sites under multidire-ctional earthquake shaking[J].Journal of Tongji University,2000,28(2):177-182.
[7]王天龙,胡文尧.上海覆盖土层的地震反应分析[A].高大钊主编.软土地基理论与实践[C].北京:中国建筑工业出版社,1992,55-61.
[8]黄雨,叶为民,唐益群,等.上海深厚饱和覆盖土层的动力耦合地震反应分析[J].岩土力学,2002,23(4):411-416.HUANG Yu,YE Wei-min,TANG Yi-qun,et al.Coupledseismic response analysis of deep saturated soil coveringlayers in Shanghai[J].Rock and Soil Mechanics,2002,23(4):411-416.
[9]周健,屠洪权,缪俊发.地下水位与环境岩土工程[M].上海:同济大学出版社,1994.
[2]刘金稻,金晓媚.饱和砂土液化判别方法中问题浅[J].工程地质学报,1992,8(3):379-384.LIU Jin-tao,JIN Xiao-mei.Preliminary analysis of themethod of discrimination of sandy soil liquefaction[J].Journal of Engineering Geology,1992,8(3):379-384.
[3]薄景山,李秀领,刘红帅.土层结构对地表加速度峰值的影响[J].地震工程与工程振动,2003,23(3):35-40.BAO Jin-shan,LI Xiu-ling,LIU Hong-shuai.Effects ofsoil construction on peak acceralations of ground motion[J].Earthauke Engineering and Engineering Vibration,2003,23(3):35-40.
[4]庄迎春,谢康和,朱益军,等.地层组合对砂土液化的影响分析[J].岩土力学,2003,24(6):991-996.ZHUANG Ying-chun,XIE Kang-he,ZHU Yi-jun,et al.Analysis for influence of multi-layered soil stratum onsand liquefaction[J].Rock and Soil Mechanics,2003,24(6):991-996.
[5]Li X S.Reduced-order sand model for ground responseanalysis[J].Journal of Engineering Mechanics,1996,122(9):872-881.
[6]蔡宏英,周健.深厚覆盖软土地层多向地震动力反应分析[J].同济大学学报,2000,28(2):177-182.CAI Hong-ying,ZHOU Jian.Elasto-plastic dynamicresponse of horizontally layered sites under multidire-ctional earthquake shaking[J].Journal of Tongji University,2000,28(2):177-182.
[7]王天龙,胡文尧.上海覆盖土层的地震反应分析[A].高大钊主编.软土地基理论与实践[C].北京:中国建筑工业出版社,1992,55-61.
[8]黄雨,叶为民,唐益群,等.上海深厚饱和覆盖土层的动力耦合地震反应分析[J].岩土力学,2002,23(4):411-416.HUANG Yu,YE Wei-min,TANG Yi-qun,et al.Coupledseismic response analysis of deep saturated soil coveringlayers in Shanghai[J].Rock and Soil Mechanics,2002,23(4):411-416.
[9]周健,屠洪权,缪俊发.地下水位与环境岩土工程[M].上海:同济大学出版社,1994.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心