CFG桩在软土地基处治中的影响参数研究

Study on Influencing Parameters in Soft Soil Foundation Treated with CFG Pile

桥头跳车问题一直是路桥过渡段不可避免的问题,梳理了CFG桩网复合地基的作用机理,并采用有限元模拟分析了CFG桩网复合地基在不同桩长、桩径、桩间距、褥垫层模量等参数变化过程中模型的沉降变化规律,明确了CFG桩网复合地基对地基沉降控制的有效性。其中复合地基桩间距的减小有利于减小地基沉降,也有利于减小CFG桩和桩间土的差异性沉降。对于CFG桩长的设置,应伸入持力层,当伸入持力层后,桩长的再增长对地基沉降降低效果甚微,同时桩径越大,CFG桩网复合地基的沉降值越小,但桩径的大小直接影响工程造价,应做适当取舍。褥垫层模量的变化对复合地基的沉降值影响较低。

The bridgehead bump is an inevitable problem in the road⁃bridge transition section.This paper generalized the mechanism of the CFG pile⁃net composite foundation and used the finite element to simulate and analyze the settlement change of the model in the process of changing parameters such as different pile lengths,pile diameters,pile spacing,and cushion modulus.It was clarified that the CFG pile⁃net composite foundation can effectively control the foundation settlement.The decrease in the pile spacing of the composite foundation could decrease the settlement and the differential settlement between the CFG pile and the soil beside the pile.The pile length should be extended into the bearing layer,after that,the further increase of the pile length had little effect on reducing the foundation settlement.The larger the pile diameter,the smaller the foundation settlement,but the pile diameter directly affected the engineering cost,which should be properly chosen.The change of the cushion modulus had a small effect on the foundation settlement.