真空预压下软土渗透系数对固结的影响

Effects of permeability coefficients on consolidation of soft clay under by vacuum preloading

考虑正常固结状态下前期固结压力对渗透系数的影响,利用ABAQUS软件,将渗透系数随固结应力的变化关系应用于真空预压下单井的三维有限元计算。计算结果表明,考虑渗透系数随固结应力的变化,其表面沉降要比渗透系数保持不变的沉降量小,固结过程较慢,相应的固结时间要长;前期固结压力越大,表面沉降将越小,达到相同固结度时所需固结时间也越长。

Considering the influence of preconsolidation pressure on permeability coefficients under normal consolidated state,the 3-D FEM numerical simulation of single drain was executed for vacuum preloading with software ABAQUS,which took the relations between permeability coefficients with consolidation stress into account.The results show that when the permeability varied with consolidation stress,the surface settlement magnitude is smaller and the course of consolidation is slower,which resulted in the time needed to finish consolidation is longer.Meanwhile,the research also shows that more the preconsolidation pressure,smaller the surface settlement is,and the time to the same consolidation degree is longer.