杭州西站红层极软岩桩基承载力参数试验研究  

Experimental Study on the Bearing Capacity Parameters of Pile in Red Layer Extremely Soft Rock at Hangzhou West Railway Station

作　　者：杭红星[1] HANG Hongxing(China Railway Siyuan Survey and Design Group Co.Ltd.,Wuhan Hubei 430063,China)

机构地区：[1]中铁第四勘察设计院集团有限公司,湖北武汉430063

出　　处：《铁道建筑技术》2022年第12期35-40,共6页Railway Construction Technology

基　　金：中铁第四勘察设计院集团有限公司科技研究开发项目(2021K019)。

摘　　要：以杭州西站桥建合一站房建设为依托,开展中风化泥质粉砂岩室内物理力学试验研究,得到泥质粉砂岩基本物理力学指标;进行4根直径1.0 m嵌岩桩单桩抗压静载荷试验,以获取桩身轴力分布特性。试验结果表明,嵌岩5 m条件下4根试桩极限承载力不小于14 000 kN;试验荷载达到10 000 kN嵌岩段桩端阻力出现明显增长,使用工况荷载下桩基承载力主要由桩侧摩阻力贡献。调研分析国内相关行业、地方规范推荐的承载力参数取值和杭州西站周边类似工程案例,综合分析后推荐杭州西站泥浆护壁钻孔桩中风化泥质粉砂岩桩侧摩阻力极限值取180 kPa,桩端阻力极限值取5 500 kPa。Based on the station building of the integrated structure(station building and bridge) of Hangzhou West Railway Station, the indoor physical mechanics experimental study on the moderately weathered argillaceous siltstone was carried out, and the basic physical and mechanical indicators of the argillaceous siltstone were obtained. The study on the static load test for single pile of the four bored rock-socketed piles with a diameter of 1.0 m was performed to obtain the distribution characteristics of the pile shaft axial force. The test results showed that the ultimate bearing capacity of the four test piles with 5 m rock socketed was not less than 14 000 kN. When the test load reached 10 000 kN, the pile tip resistances of the rock-socketed sections were increased significantly, and the bearing capacity of the pile foundation under service load was mainly from the pile friction. After investigating and analyzing the bearing capacity parameters recommended by the relevant domestic industries and local norms and the similar cases around Hangzhou West Railway Station, it is recommended that the pile friction ultimate value of moderately weathered argillaceous siltstone of slurry bored pile at Hangzhou West Railway Station will be 180 kPa, and the ultimate value of pile tip resistance will be 5 500 kPa through comprehensive analysis.

关 键 词：泥质粉砂岩 极软岩 试桩 桩端阻力 桩侧摩阻力 试验 

分 类 号：TU473.1[建筑科学—结构工程]