含弱渗透夹层饱和砂土液化后水膜形成的数值模拟  

Numerical simulation of water film formation in saturated sand soils with weak permeability interlayers after liquefaction

作　　者：王炳辉[1] 魏文豪 金丹丹[2] 许帅 张雷 WANG Binghui;WEI Wenhao;JIN Dandan;XU Shuai;ZHANG Lei(School of Civil Engineering and Architecture,Jiangsu University of Science and Technology,Zhenjiang,Jiangsu 212100,China;Faculty of Civil Engineering and Mechanics,Jiangsu University,Zhenjiang,Jiangsu 212013,China)

机构地区：[1]江苏科技大学土木工程与建筑学院,江苏镇江212100 [2]江苏大学土木工程与力学学院,江苏镇江212013

出　　处：《江苏大学学报（自然科学版）》2024年第6期725-731,共7页Journal of Jiangsu University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51978317);江苏省自然科学基金青年基金资助项目(BK20200996)。

摘　　要：针对含弱渗透夹层饱和砂土液化产生水膜对砂土强度和变形指标分布产生的影响,建立了一维饱和砂土液化水膜的有限差分模型,对含弱渗透细砂夹层的饱和砂土液化过程中水膜形成的机制及其发展、消散过程进行模拟,分析土层尤其是夹层的特性参数与水膜变化之间的关系.结果表明:超孔隙水压力消散过程中会出现明显的平台阶段,其起、止点时刻正好与水膜最大厚度形成和水膜消失时刻具有较好的对应关系;水膜的形成和发展与高孔压的持续时间密切相关,含弱渗透夹层中,其下方会产生水膜,且饱和砂土中高孔压作用的时长较无夹层明显延长,从而对土体变形产生不利影响;通过与已有试验结果的对比分析,验证了该模型的合理性.To investigate the influence of water film produced by the liquefaction of saturated sand with weak permeability on the distribution of sand strength and deformation index,the one-dimensional finite difference model of liquefied water film in saturated sand was established to simulate the formation mechanism,development and dissipation process of water film in the liquefaction process of saturated sand with weak permeability fine sand,and the relationship between the water film and the characteristic parameters of soil layer for especially the interlayer.The results show that there is obvious plateau stage in the process of excess pore water pressure dissipation,and the starting and ending points have good relationship with the formation of the maximum thickness and disappearance of the water film.The formation and development of water film is closely related to the duration of high pore pressure.In the case of weak permeability interlayer,the water film is produced under the interlayer,and the duration of high pore pressure application in saturated sand is significantly longer than that without interlayer,which has adverse effect on soil deformation.The rationality of the model is verified by comparing with the experimental results.

关 键 词：水膜 饱和砂土 孔压消散 弱渗透夹层 土体应变 数值模拟 

分 类 号：TU411[建筑科学—岩土工程]