黄土高速铁路路基注浆扩散范围模型试验研究

Model Experimental Study on Diffusion Range of Grouting Slurry of High-speed Railway Subgrade in Loess Areas

为研究黄土高速铁路路基注浆加固中浆液扩散规律,以大西高速铁路沿线典型湿陷性黄土路基为研究对象,开展注浆模型试验及Edem-Fluent耦合数值仿真,得到黄土注浆扩散范围及注浆盲区参数。试验结果表明:随着注浆压力的增大,浆液的扩散范围逐渐扩大,加固体长度与注浆压力近似幂指数关系。Edem-Fluent耦合仿真分析得到的注浆扩散范围与试验相符合。力链分析表明注浆压力越大,土体间的微观作用力作用越分散,在浆液劈裂方向上,注浆压力是呈消散分布。在此基础上推导了黄土注浆浆液扩散范围及注浆扩散盲区计算公式。

To study the diffusion law of grout in grouting reinforcement of subgrade of high-speed railway in loess areas,model tests and Edem-Fluent coupled numerical simulation were conducted on typical collapsible loess subgrade along the Datong—Xi’an High-speed Railway,to obtain the range of grout diffusion in loess and parameters for blind zone during grouting.The research findings indicate that as the grouting pressure increases,the diffusion range of the slurry gradually expands,with the length of the reinforcement showing approximately exponential relationship with the grouting pressure.The diffusion range of grouting obtained from the coupled simulation of Edem-Fluent is consistent with model tests.The force chain analysis indicates that as the grouting pressure increases,the micro-interaction forces between soil particles become more dispersed.In the direction of slurry splitting,the grouting pressure exhibits a dissipative distribution.Based on the above,the formulas for calculating the diffusion range of loess grout slurry and the blind zone of grouting diffusion were derived.