(1西南交通大学岩土工程系， 成都 610031； 2铁道第三勘察设计院集团有限公司， 天津 300142)

［摘要］为了对桩筏结构载体桩复合地基在高速铁路深厚软弱地基加固中的沉降特性进行研究，采用单点沉降计与液位沉降计的联合监测法，在京沪高速铁路廊坊试验段进行了载体桩与CFG桩复合地基沉降变形的对比试验。结果表明：本试验段工后沉降均满足设计要求；受桩长影响，载体桩复合地基沉降约为CFG桩复合地基的2倍，同时其沉降稳定所需时间也相对较长。

［关键词］高速铁路; 载体桩; CFG桩; 桩筏基础; 沉降变形

中图分类号：TU473        文献标识码：A        文章编号：1002-848X(2014)08-0037-03

Research on settlement characteristics of ram-compacted piles with bearing base composite foundation

Chen Hongyun1, Ma Jianlin1, Xu Zailiang2, Song Xuguo2

 (1 Geotechnical Engineering Department, Southwest Jiaotong University, Chengdu 610031, China; 2 The Third Railway Survey and Design Institute Group Corporation, Tianjin 300142, China)

Abstract: To study the settlement characteristics of ram-compacted piles with bearing base (RPBB) composite foundation with pile-raft structure, which is used to reinforce the deep and soft foundation of high-speed railway, tests on settlements of RPBB and cement fly-ash gravel (CFG) piles composite foundations were carried out and compared in the Langfang test section of the Beijing-Shanghai high speed railway by the combined test method of the single-point settlement meter and the hydrostatic level. Results show that the settlements after construction all meet the design requirements in the test section. Because the reinforced depth of RPBB is limited, the settlement of RPBB composite foundation is about double of CFG pile composite foundation settlement and times needed to the settlement stabilization of the RPBB composite foundation lasts longer.

Keywords: high-speed railway; ram-compacted piles with bearing base; cement fly-ash gravel pile; pile-raft foundation; settlement and deformation

*铁道部京沪高速铁路科技重大专项（2008G32-A）。

作者简介：陈洪运，博士研究生，Email: 278709407@qq.com。

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