抗滑桩加固边坡稳定性及影响因素的有限元分析

Finite element analysis for slope stability and its influencing factors with pile reinforcement

通过Fortran95语言编制边坡在抗滑桩加固情况下的稳定性程序(FPS),并与商业软件FLAC3D的计算结果进行对比,以验证程序的正确性及优越性;然后,通过抗滑桩支护参数对边坡稳定性的影响进行分析。研究结果表明:(1)当桩长较小时,抗滑桩设置在边坡中下部对稳定性最有利,当桩长较大时,抗滑桩设置在边坡中间对稳定性最有利;(2)桩长对于边坡安全系数的影响程度与抗滑桩布置的位置有关,当抗滑桩位于坡顶或者坡脚时,桩长的变化对于安全系数的影响很小;而抗滑桩位于边坡坡面中央时,在桩的长度达到临界桩长之前,边坡的安全系数与桩长呈显著的线性关系;(3)随着桩长的不断增大,潜在滑动面逐渐向边坡内部移动,破坏模式由浅层滑动变为深层滑动,安全系数也不断增大;但当桩长达到一定程度后,边坡的临界滑动面转移到临坡面位置。

A program named FPS was compiled with Fortran95 for the slope stability analysis with pile reinforcement,the results from FPS were compared with those from commercial software FLAC3D for validation,and the efficiency of FPS was discussed.Then the influences of the pile reinforcement parameters on the slope stability were studied.The results show that（1） when the pile length is shorter,it is suggested to drive pile at the lower part of slope;while the pile length is longer,it is suggested to drive pile at the middle of slope surface;（2） the effect of pile length on slope safety factor is related to pile location;when the pile is driven at the slope vertex or slope toe,the pile length has little effect on the slope safety factor;while the pile is driven at the middle of slope surface and before the pile length reaches the critical pile length,the safety factor increases greatly with the pile length in the linear relationship;（3） with the increase of pile length,the slope potential slip plane moves gradually to the inner place,failure mode of slope changes from shallow slipping to deep slipping,and the slope safety factor increases as well;but when the length of pile reaches some magnitude,the potential slip plane moves close to slope surface.