Reinforcement effect and stability analysis of high speed railway roadbed

Abstract

In order to determine reinforcement effects and technical parameters of dynamic compaction on roadbedꎬ with silt and silty clay roadbed of a high speed railway as research objectꎬ bearing capacity and deformation law and features of reinforced roadbed by dynamic compaction at 15 and 20 m falling distances were studied through site experiment and numerical simulation. The results show that as tamping times increaseꎬ compaction settlement for each tamping decreases and gradually stabilizesꎬ and settlements of last two tamping of each falling distance can meet termination condition of engineering design. When dynamic compaction is appliedꎬ water contentꎬ dry density and specific penetration resistance of surface soil are all significantly improved with obvious reinforcement effect achieved in efficient reinforcement area. 第 6 期 贾剑青等: 高速铁路路基加固效果及稳定性分析 And bearing capacity characteristic values of roadbeds in three test points are greater than 150 kPaꎬ which meets designing requirements. In early stage of dynamic compactionꎬ numerical simulation results are slightly smaller than those of field testꎬ but they agree well with each other as tamping times increase.