非等温条件下土体固结变形及溶质运移规律分析  

Analysis on soil consolidation deformation and solute transport under non-isothermal conditions

作　　者：田改垒 张志红[1] Tian Gailei;Zhang Zhihong(Beijing Key Laboratory of Earthquake Engineering and Structural Retrofit, Beijing University of Technology, Beijing 100124, China)

机构地区：[1]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124

出　　处：《东南大学学报（自然科学版）》2021年第5期819-825,共7页Journal of Southeast University：Natural Science Edition

基　　金：科技部“第二次青藏高原综合科学考察研究”专项资助项目(2019QZKK0905-04).

摘　　要：为探究非等温条件下黏土垫层固结变形及溶质运移规律,将综合考虑力学固结、化学渗透固结及热固结影响的热水力化(THMC)全耦合模型与水力化(HMC)耦合模型进行对比分析,研究了温度差对孔隙水压力、土体变形及溶质运移进程的影响.结果表明,垫层上下边界温度差可加快负孔隙水压力消散,增大土体沉降峰值及回弹量,提高溶质运移速率.随着黏土垫层上下边界温度差的增加,温度差对孔隙水压力、土体变形及溶质运移进程的影响程度进一步加大.当模拟时间为50 a,温度差为40℃时,与HMC模型相比,THMC模型所对应的负孔隙水压力峰值减小42%,土体沉降回弹量扩大5.4倍,溶质击穿时间缩短11.4 a.该研究可为填埋场防渗垫层设计及服役性能评估提供参考.To investigate the consolidation deformation and the solute transport of clay cushion under non-isothermal conditions,a thermos-hydro-mechanical-chemical(THMC)coupled model comprehensively considering the effects of mechanical consolidation chemical-osmotic consolidation and thermal consolidation was compared with the hydro-mechanical-chemical(HMC)coupled model,and the influences of the temperature difference on pore water pressure,soil deformation and solute migration were studied.The results show that the temperature difference between the upper and lower boundaries of the clay liner can accelerate the dissipation of the negative pore water pressure,increase the peak value of the soil settlement and the subsequent rebound and accelerate the solute migration rate.With the increase of the temperature difference between the upper and lower boundaries of the clay liner,the influences of temperatures on the pore water pressure,the soil deformation and the solute transport are further increased.When the simulation time is 50 a and the temperature difference of the clay liner is 40℃,compared with the HMC coupled model,the maximum negative pore water pressure corresponding to the THMC model decreases by 42%,the rebound amount of the settlement increases by 5.4 times and the breakthrough time of contaminants decreases by 11.4 a on THMC coupled model.The research can provide a reference for the design and the evaluation of the anti-seepage clay liner of landfill.

关 键 词：温度差 黏土垫层 热水力化 水力化 溶质运移 

分 类 号：TU443[建筑科学—岩土工程]