铁路客运专线黄土路基沉降因素敏感性分析

Sensitivity Analysis of the Factors to Loess Roadbed Settlement of Passenger Dedicated Lines

采用有限元分析软件ANSYS对CFG桩筏结构黄土铁路路基沉降进行研究,针对不同的影响因素,计算出各自的敏感度,找出影响黄土铁路路基沉降的主要因素.计算研究表明:采用CFG桩筏结构处理黄土铁路路基时,可以使路基沉降控制在一定范围内;在影响路基沉降的诸多因素里,CFG桩桩长的敏感度最大,黄土层厚度次之;在黄土土体各参数中,弹性模量对路基的沉降比较明显,泊松比和粘聚力对路基的沉降影响不明显;褥垫层厚度对沉降的影响比较大,根据分析,褥垫层厚度为20 cm左右时较为合理;在黄土路基的处理措施中,增大CFG桩桩长对控制路基沉降有明显效果.

In this paper,research on settlement of piled raft railway foundation was conducted by using ANSYS.Aiming at different factors,the respective sensitivity was figured out and the main factor to settlement was located. When using CFG piled raft foundation,the settlement can be controlled within a specific range. Among all the factors,the CFG pipe length is the most impontant influencing factor,and the thickness of loess layer is inferior. In the loess soil parameters,the elastic modulus on the roadbed settlement is obvious,the influence of cohesion and poisson ratio on the roadbed settlement is not obvious; Mattress layer thickness has bigger influence on the settlement,according to the analysis,reasonable mattress layer thickness is 20cm; In handled measures of loess railway roadbed,increasing the CFG pipe length have an obvious effect on the control of roadbed settlement.