水泥土挤密桩复合地基桩土应力比的现场测试研究  

Field Experiment of Pile-soil Stress Ratio of Cement-soil Compaction Piles Composite Foundation

作　　者：杨有海[1] 陶天森[1] 郭建群 陶福金 

机构地区：[1]兰州交通大学土木工程学院,甘肃兰州730070 [2]中铁七局集团有限公司,河南郑州450016

出　　处：《铁道学报》2008年第3期91-95,共5页Journal of the China Railway Society

基　　金：铁道部科技研究开发计划项目(2004G029)

摘　　要：桩土应力比n是复合地基设计中的重要参数。本文依托郑（郑州）西（西安）客运专线工程进行水泥土挤密桩复合地基桩、土应力的现场测试，得到桩土应力比”在路堤填筑过程中的变化规律。在刚性荷载板下的单桩复合静载试验测得，加载过程中n值变化快，且存在明显的峰值；而在路堤荷载下，n值变化较缓慢，量值比载荷试验的结果小得多，且变化范围不大，最终趋于一个稳定值。n取值范围为1．77～3．55，平均值为2．66。分析在路堤填筑过程中复合地基桩、土工作性状，进一步说明刚柔基础复合地基承载特性的差异，为铁路工程的设计施工提供合理的桩土应力比取值范围。The pile-soil stress ratio n is the important parameter in design of the composite foundation. In this paper, stresses are measured on piles and soil in the field test of the cement-soil compaction pile composite foundation on the Zhengzhou-Xi＇an Passenger Line and the variation rule of n in embankment filling is found. In the test of the single-pile composite static loading under stiff loading plate, n varies fast in loading and exhibits apparent peak values. In the embankment loading test, n varies slowly in a small range and finally tends to become stabe;the n values are much less than those in the static loading test. The values of n are chosen between 1.77 and 3.55 with an average of 2.66. The working mechanism of pile and soil during the process of embankment filling is analyzed. The differences of the composite foundation bearing characteristics between the rigid base and the flexible base are expounded. A rational numerical value range of n is provided for design and construction.

关 键 词：水泥土挤密桩 桩土应力比 柔性基础 现场测试 湿陷性黄土 载荷试验 

分 类 号：U213.1[交通运输工程—道路与铁道工程]