高速铁路CFG桩-筏结构沉降控制现场试验

Research on Settlement Control Effect of CFG Pile-raft Structure Based on Field Test of High-speed Railway

研究目的：通过对京沪高速铁路典型工点现场地基沉降试验研究，掌握CFG桩加固后的深厚松软土地基加固区与下卧层的压缩沉降及地基总沉降变形规律，进一步评价高速铁路CFG桩-筏结构处理深厚层地皋的沉降控制效果。研究结论：现场实测数据表明：（1）CFG桩-筏结构路基的工后沉降满足规范要求；（2）下卧层沉降是沉降的主要组成部分，约占总沉降的74％；（3）桩-筏结构的地基沉降控制效果要好于桩-帽-网结构，本文试验条件下，前者沉降约为后者的73．5％-75％；（4）分析表明，对于沉降要求严格的无砟轨道软土路基可优先采用桩-筏基础结构型式。

Research purposes： Field tests were conducted at a CFG pile - raft structure working point of Beijing - Shanghai High - speed Railway to investigate the deformation law of reinforced zone and substratum compression and total settlement. A further evaluation was made to investigate the settlement control effect of deep foundation treatment with CFG pile -raft structure. Research conclusions： The result indicates that： （ 1 ） The settlement of CFG pile - raft structure meets standard requirements. （2） The substratum settlement is the main part of total settlement, which accounts for 74% of total settlement. （3） The foundation settlement control effect of CFG pile - raft structure is better than that of CFG pile - cap - net. Under current test conditions, the ratio of the formerg total settlement to the latterg is 73.5 -75%. （4） The analysis showed that, CFG pile -raft structure can be used in preference in unballasted track on soft soil subgrade.