CFG桩加固高铁软土路基的动力数值分析

Numerical Analysis of Dynamics of Soft Soil Subgrade of High-speed Railway Reinforced by CFG Pile

为研究CFG桩对高速铁路软土路基的加固效果,以福州至平潭高铁松下车站为依托,采用弹塑性有限元法,在模拟列车移动荷载的基础上,对软土路基在采用CFG桩加固前后的动力响应进行分析,研究了竖向速度、加速度及压应力的一般规律。结果表明:在CFG桩加固后,路基面竖向速度和加速度在路基面下0.3m以内减幅相对较小;0.3～3m范围内衰减速度较快;3m以上时,减幅基本接近0;CFG桩在减少列车动荷载对路基影响方面加固效果明显。

In order to study the reinforcement effect of CFG pile on soft soil subgrade of highspeed railway, based on Songxia station of Fuzhou-Pingtan high-speed railway, the dynamic response of soft soil subgrade before and after reinforcement with CFG pile was analyzed by using elastic-plastic finite element method on the basis of simulating the moving load of train, and the general laws of vertical velocity, acceleration and compressive stress were studied. The results show that after reinforcement of CFG pile, the vertical velocity and acceleration of subgrade surface decrease relatively small within 0.3 m below the subgrade surface; the attenuation speed is faster within 0.3-3 m; when it is below 3 m, it is nearly 0; The CFG pile has obvious reinforcement effect in reducing the impact of train dynamic load on the roadbed.