高速铁路岩溶地区桩基后压浆试验研究  

Experimental Study on Post Grouting of Pile Foundation of High-speed Railway in Karst Area

作　　者：白丁伟 马建林[1] 李兴国 孙卫星 BAI Ding-wei;MA Jian-lin;LI Xing-guo;SUN Wei-Xing(School of Civil Engineering Southwest Jiaotong University,Chengdu 610031,China;Jing-Shen Dedicated Passenger Railway JingJi Co.,Ltd.;CCCC Third Harbor Engineering Bureau,Shanghai 200940,China)

机构地区：[1]西南交通大学土木工程学院,成都610031 [2]京沈铁路客运专线京冀有限公司,北京100161 [3]中交第三航务工程局,上海200940

出　　处：《铁道标准设计》2018年第6期83-88,共6页Railway Standard Design

基　　金：国家重点研发计划(2016YFC0802203-1)

摘　　要：京沈高铁顺义特大桥189号、190号墩地处岩溶发育区,原设计桩长需穿越岩溶地层,施工难度大,进度、成本计划难以保证,现通过桩端、桩侧压浆技术改善承载性状。为获得后压浆技术相关参数及效果,在现场开展桩基后压浆静载试验。采用《建筑桩基技术规范》对压浆前后灌注桩进行承载力计算,对比分析试桩在不同荷载条件下的桩顶位移、桩侧摩阻力值、桩端阻力值。试验结果表明:后压浆工艺可有效提高基桩承载力,减少桩顶沉降;提高侧摩阻力占比,并显著提高在距桩顶10 m以下范围内砂性土的侧摩阻。The 189# and 190# piers of Shunyi major bridge on Beijing-Shenyang high-speed railway are located in the karst area. The original designed piles need to pass through the karst stratum and it ＇s difficult to make it,and the progress and cost plan are difficult to guarantee. The bearing capacity is improved by post grouting technique in pile tip and pile side. In order to obtain the parameters and effects of post grouting,static loading test of pile foundation is carried out in situ. In this paper,the calculation of bearing capacity of bored piles before and after grouting is conducted following Technical Code for Building Pile Foundations,in which pile top displacement,lateral friction of pile and pile tip resistance under different loading conditions are compared and analyzed. The results show that the post grouting process can improve effectively the bearing capacity of pile,reduce the pile top settlement,increase the proportion of lateral friction resistance and finally significantly improve the lateral friction resistance of sandy soil in the range of 10 m below the pile top.

关 键 词：岩溶发育区 桩基础 压浆 静载试验 高速铁路 

分 类 号：TU473.11[建筑科学—结构工程] U445.552[建筑科学—土工工程]