块石压填法处置软土路基的敏感性参数分析

Sensitivity Parameter Analysis of Soft Soil Foundation Treated by Block-Stone Filling Method

为了更好地评价天然软土路基加固处理效果,采用基于上下负荷面的弹黏塑性本构模型,表征天然软土地基的力学特性,利用大型有限元软件ABAQUS建立模型,模拟路堤分层填筑过程,获取采用块石压填法处置后的软土路基承载力和变形特征。分析了不同块石换填层厚度、变形模量、不同堆载荷载及填筑时长对软土路基的承载力以及工后沉降变形的影响特征。结果表明:基于上下负荷面的弹黏塑性本构模型能够有效地模拟软土路基的变形特征,能用于复杂路基的工后沉降分析;块石压填层的厚度以及变形模量均对地基承载力有显著影响,块石压填层的厚度、填筑时长以及堆载均对工后沉降有显著影响,而块石压填层变形模量并不对工后沉降产生明显影响。

In order to better evaluate the treatment effect of the natural soft soil reinforcement, an elastoviscoplastic constitutive model based on super-subloading surface has been used to describe the mechanical characteristics of the natural soft soil foundation. By using finite element method software ABAQUS, a simulation can be achieved of the layer-filled process of embankment, thus obtaining the bearing capacity and deformation characteristics of the soft soil foundation treated by block-rock compaction method. An analysis has been made of the influence of different thickness, modulus of deformation, different loading and filling time on the bearing capacity of soft soil roadbed and post-construction settlement and deformation. The results show that the elasto-viscoplastic constitutive model based on super-subloading surface can effectively simulate the deformation characteristics of the soft soil foundation, which can be used for post-construction settlement analysis of complex subgrade. Thickness and modulus of deformation of rock fill have significant effects on the bearing capacity of foundation. Moreover, thickness, length of filling and surcharge of rock fill have significant effects on post-construction settlement, while modulus of deformation of rock fill has no significant effect on post-construction settlement.