Numerical simulation of settlement of cement-soil mixing pile subgrade of large-scale soft soil first-class highway

Based on the engineering background of large-scale soft soil in Zhanjiang avenue of the first-class highway, numerical simulation of settlement law of first grade highway subgrade with soft soil is carried out, aiming at the construction difficulties such as settlement easily caused by highway subgrade and uneven settlement of pavement. A finite element model considering embankment-foundation-cement-soil mixing pile is established by using Midas/GTS. The subgrade settlement and deformation laws under two conditions of pile-setting and non-pile-setting and influence of elastic modulus of pile, length of pile and area replacement ratio of cement-soil mixing pile on subgrade settlement are studied. The results show that using cement-soil mixing pile to treat soft soil foundation can effectively reduce post-construction settlement, the elastic modulus and length of pile have little influence on post-construction settlement and the settlement control effect and economic cost should be considered comprehensively when selecting area replacement rate. © 2020, Central South University Press. All rights reserved.