一维饱和冻土融化固结分析  

One dimensional thaw settlement of saturated frozen soil

作　　者：明锋[1] 李东庆[1] 张宇[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,甘肃兰州730000

出　　处：《冰川冻土》2016年第4期1067-1073,共7页Journal of Glaciology and Geocryology

基　　金：国家科技支撑计划项目(2014BAG05B03);国家自然科学基金项目(41271080);冻土工程国家重点实验室自主课题(SKLFSE-ZQ-35)资助

摘　　要：冻土的融化固结是在融化的基础上进行的,是温度与变形耦合作用的结果.根据考虑冰水相变的热传导方程和水分迁移方程,建立以孔隙比为变量的融化变形固结理论.利用有限元软件对冻土一维融化固结进行数值模拟,分析了融化过程中孔隙比、孔隙水压力、变形等随时间的变化规律,并与实验结果进行对比.研究表明:含水率的增大会阻碍融化锋面的推进速率,进而降低土体固结速率,而且冻土的固结过程滞后于冻土的融化过程.随着融化锋面的移动,固结区域不断增大.冻土的融化固结过程也是孔隙水的消散过程,随着孔压的不断消散,变形量逐渐增加.最大位移出现在土体表面,最大沉降量随时间增长而增大,最后趋于一个稳定值.For the frozen soil,the consolidation process is on the basis of the soil melting. Based on the heat conduction equation,which considering water phase change and the moisture migration equation,a thaw-consolidation theory was presented,which take the void ratio as the variable. The effectiveness of this algorithm is verified by the sample application. The void ratio and pore water pressure and deformation with time change lawwere analyzed,and compared with the experimental results. It was proved that the simulated data have a good agreement with tested results. The results showthat the increasing of water content decreased the movement speed of the thawing front. As a result,the rate of consolidation is decreased. The consolidation process lags behind the thawing process. With the thawing front downstairs,the consolidate happens in a larger area. The thawconsolidation process is a process of dissipation of pore water pressure. the deformation is increased with the dissipation of pore water pressure. The deformation increased with the increasing of consolidation degree,and then tend to a stable value,furthermore,the largest displacement appeared at the top end of the soil column.

关 键 词：冻土 水分迁移 融沉变形 数值模拟 

分 类 号：P642.14[天文地球—工程地质学]