振冲碎石桩处治粉砂性湿软地基研究

A Study on Treating Wet and Soft Sandy Silt Subgrade by Using Vibro-Replacement Stone Column

为了提高粉砂性湿软地基的承载能力,采用振冲碎石桩进行处治.基于Drucker-Prager模型,应用数值分析软件对实际工程中加固后的不同填高路基及不同桩径、不同桩间距的碎石桩复合地基进行数值模拟.结果表明,随着碎石桩桩径的增大、桩间距的减小,振冲碎石桩能减少路基沉降量,最大减小量分别为31.4 mm和23.4 mm,但坡脚的水平位移增大;随着路基填高和桩间距的增大,碎石桩复合地基坡脚的水平位移减小.综合分析认为,当桩径为0.5 m且桩间距为1.5 m时,较为经济合理.

In order to improve the bearing capacity silty of sand soft ground,vibro-replacement stone column was used to strengthen it.Based on Drucker-Prager model,the reinforcement of vibro-replacement stone column composite foundation of different height of roadbed,different pile diameter and pile spacing were respectively simulated with the numerical analysis software.Results showed that with the increase of pile diameter,spacing and decreasing vibro-replacement stone column the maximum of roadbed subsidence reduce 31.4mm and 23.4mm,respectively.At the same time,along with the high and roadbed banquette pile spacing,the increasing of vibro-replacement stone column composite foundation slope horizontal displacement reduces,but as pile diameter grows,horizontal displacement of slope toe increases.On the basis of comprehensive analysis,it is concluded that the pile diameter is 0.5m and the distance between piles is 1.5m,which is more economical and reasonable than the other.