碎石桩-水平垫层联合法处理软土路基的数值仿真分析  

Numerical simulation analysis of the combined method of gravel pile and horizontal cushion layer for treating soft soil subgrade

作　　者：秦兴锋 史冠宇 QIN Xingfeng;SHI Guanyu(Jiangsu Province Engineering Investigation and Research Institute Co.,Ltd.,Yangzhou 225000,China)

机构地区：[1]江苏省工程勘测研究院有限责任公司,江苏扬州225000

出　　处：《江苏水利》2024年第9期64-68,共5页Jiangsu Water Resources

摘　　要：软土具有透水性差、强度低、压缩性高等缺点,在软土上修建道路易发生沉陷、坍塌等问题。依托江苏省某软土地区道路修建工程背景,采用有限元软件Plaxis2d建立路堤模型,模拟了软土路堤填筑过程,分析了经碎石桩-水平垫层联合法加固后的地表沉降以及地基承载力规律,评估了碎石桩-水平垫层联合法的加固效果。研究表明,经碎石桩-水平垫层联合法加固后的地基承载力较天然地基提升了近4倍,可到316.85kPa;受非均布堆载影响,路堤填筑过程中会产生不均匀沉降,且碎石桩桩身会发生鼓胀变形。加设水平垫层后,地表最大不均匀沉降以及桩身最大鼓胀分别减小了17.1%和16.9%,说明加设水平垫层对地表沉降和桩身位移限制作用显著。Soft soil has the disadvantages of poor permeability,low strength,and high compressibility.Modifying roads on soft soil is prone to problems such as settlement and collapse.Therefore,based on the background of a road construction project in a soft soil area of Jiangsu Province,the finite element software Plaxis2d is used to establish an embankment model,the filling process of soft soil embankments is simulated,the surface settlement and subgrade bearing capacity after reinforcement by the combined method of gravel piles and horizontal cushion layers are analyzed,the reinforcement effect of the combined method of gravel piles and horizontal cushion layers is evaluated.Research has shown that the bearing capacity of the subgrade reinforced by the combined method of gravel pile and horizontal cushion layer is nearly 4 times higher than that of natural subgrade,reaching 316.85kPa;Due to the influence of non-uniform stacking load,uneven settlement will occur during the embankment filling process,and the gravel pile body will experience bulging deformation.After adding a horizontal cushion layer,the maximum uneven settlement on the surface and the maximum swelling of the pile body decreased by about 17.1%and 16.9%,respectively,indicating that the addition of a horizontal cushion layer has a significant effect on limiting surface settlement and pile displacement.

关 键 词：软土地基 碎石桩-水平垫层 地基承载力 地表沉降 数值仿真 

分 类 号：TV553[水利工程—水利水电工程]