高速铁路采空区桩板结构复合路基受力机理数值模拟  

Numerical Simulation on Stress Mechanism of Sheet-Pile Composite Subgrade of High-speed Railway in Goaf Area

作　　者：梁鑫[1,2] 程谦恭[1] 王长宝[1] 李传宝[3] 

机构地区：[1]西南交通大学,成都610031 [2]广西科技大学,柳州545006 [3]中铁第四勘察设计院集团有限公司,武汉430063

出　　处：《铁道标准设计》2014年第4期1-5,共5页Railway Standard Design

基　　金：铁四院科技研究开发计划课题(2010K31)

摘　　要：桩板结构在国内多条高速铁路软土和黄土路基中已得到广泛应用,但该结构用于处理路基采空区的研究成果不多。以合肥至福州高速铁路采空巷道上方车站桩板复合路基为研究对象,数值模拟分析路基的受力机理。研究表明:桩身轴力呈上大下小变化趋势,所有桩均为端承摩擦桩,穿过采空巷道的桩在采空巷道范围内轴力保持不变;所有桩桩侧摩阻力都呈现出先增大后减小的趋势,桩的侧摩阻力分布重心下移,穿过采空区的桩侧摩阻力分布重心要比未穿越采空区的桩要深,桩身越长侧摩阻力所占承载力比例越大;采空区复合路基的桩土应力比要比软土路基的小。Sheet-pile structure had been widely used for treating the soft soil or loess soil subgrade of domestic high-speed railway, but for treating the goaf area, there was little research result. For this reason, in this study, the sheet-pile composite subgrade above a goaf roadway at a station of Hefei- Fuzhou high-speed railway was taken as research object, and the numerical simulation was conducted to analyze the stress mechanism of this subgrade. The research results show that： （a） The axial force along the pile shaft presents a change trend of large top and small bottom basically; all of the piles are end-bearing friction piles ; the axial forces of pile shafts within the range of goaf roadway remain the same during passing through the goaf roadway. （b） All of the pile side frictions present a trend of increasing first and then decreasing; and the orthocenter of pile side friction distribution is downward, especially the orthocenter of pile side friction distribution of the piles in the goaf area is much deeper than that of piles not in the goaf area; the longer the pile shaft is, the greater the proportion of side friction in bearing capacity becomes. （c） The pile-soil stress ratio of composite subgrade in goaf area is smaller than that of subgrade in soft soil.

关 键 词：高速铁路 采空区 桩板结构 受力机理 数值模拟 

分 类 号：U238[交通运输工程—道路与铁道工程] U213.14