水泥土搅拌桩加固铁路饱和黄土地基承载特性试验及分析  

Test and Analysis of Bearing Characteristics of Railway Saturated Loess Foundation Reinforced by Cement-soil Mixing Pile

作　　者：安芃芃 杨有海[2] 付清华[1] 李铁根 周贺 AN Pengpeng;YANG Youhai;FU Qinghua;LI Tiegen;ZHOU He(Gansu Vocational College of Communications,Lanzhou,Gansu 730070,China;Lanzhou Jiaotong University,Lanzhou,Gansu 730070,China)

机构地区：[1]甘肃交通职业技术学院,甘肃兰州730070 [2]兰州交通大学,甘肃兰州730070

出　　处：《黑龙江交通科技》2024年第5期1-5,共5页Communications Science and Technology Heilongjiang

基　　金：中国铁路总公司科研项目——水泥土搅拌桩复合地基加固不同等级铁路饱和黄土地基研究(2013G009-N)。

摘　　要：针对兰州西至中川机场城际铁路沿线分布着大量饱和黄土,天然承载力低,无法满足工程建设要求这一问题,依据复合地基理论,提出用水泥土搅拌桩加固饱和黄土地基。通过FLAC 3D软件建立柔性荷载作用下水泥土搅拌桩复合地基模型,进行承载特性分析。得出以下结论:复合地基承载力为150 kPa,较原位地基土的承载力100.24 kPa有明显的提高;随着上部荷载的增加,沉降量也增大,中桩沉降量最大,边桩次之,角桩最小;桩身轴应力沿深度变化曲线存在一个中性点,此处桩身轴应力达到最大值;桩顶应力、桩间土应力随着荷载增加而增大,荷载为180 kPa是增长幅度发生变化的转折点。A large amount of saturated loess is distributed along the intercity railway from Lanzhou West to Zhongchuan Airport,and its natural bearing capacity is low,which cannot meet the requirements of engineering construction.According to the theory of composite foundation,the saturated loess foundation is strengthened by mixing piles with soil-water.FLAC 3D software was used to establish the composite foundation model of soil-mixed pile under flexible load and analyze the bearing characteristics.The results are as follows:the bearing capacity of the composite foundation is 150 kPa,which is significantly higher than that of the in-situ foundation soil 100.24 kPa.With the increase of the upper load,the settlement of the middle pile is the largest,followed by the side pile and the corner pile.There is a neutral point in the curve of pile axial stress along the depth,where the pile axial stress reaches the maximum value.The pile top stress and soil stress between piles increase with the increase of load,and the load of 180 kPa is the turning point of the change of growth amplitude.

关 键 词：水泥土搅拌桩 铁路 复合地基 FLAC 3D 数值模拟 

分 类 号：U416.1[交通运输工程—道路与铁道工程]