桩端后压浆钻孔灌注桩提高桩基承载力的应用研究  

Study on the Application of Improving the Pile Foundation Bearing Capacity Through Pile Tip Post-Grouting Bored Pile

作　　者：焦清杰 JIAO Qingjie(China Railway Fifth Survey and Design Institute Group Co.Ltd.,Beijing 102600,China)

机构地区：[1]中铁第五勘察设计院集团有限公司,北京102060

出　　处：《铁道建筑技术》2022年第4期66-68,182,共4页Railway Construction Technology

摘　　要：为促进桩端持力层整体强度得以充分发挥,进一步提高后压浆钻孔灌注桩单桩承载力,本文依托温州市域铁路S1线灵昆车辆段上盖开发工程进行桩端后压浆技术应用研究,对比分析压浆试桩与未压浆试桩试验检测结果,结合桩端内力测试与载荷试验Q-S曲线特征,综合研究后压浆灌注桩承载性能,并对桩端后压浆技术提高单桩承载力作用机理进行探讨。试桩检测结果表明:后压浆技术可提高桩端持力层桩端阻力约43%,提高单桩桩基承载力约30%,可有效减少桩基沉降,显著节约工程造价。In order to promote the full play of overall strength of the bearing layer at pile tip and further improve the bearing capacity of single pile of post-grouting bored pile,this paper is based on the Wenzhou Municipal Railway S1 Line upper-cover development project of Lingkun vehicle segment to study the application of post-grouting technology at pile tip.Through comparing and analyzing the test results of grouting test pile and non-grouting test pile,combined with the pile tip internal force test and Q-S curve characteristics of the load test,the bearing performance of post-grouting bored pile is comprehensively studied,and the mechanism of post-grouting technology at pile tip to improve the pile bearing capacity is discussed.The pile test results show that the post-grouting technology can improve the pile tip resistance of the bearing layer at pile tip by about 43%and increase the bearing capacity of the single pile foundation by about 30%,reduce the settlement of the pile foundation,and significantly save the engineering cost.

关 键 词：桩基 桩端后压浆 极限承载力 桩端阻力 载荷试验 

分 类 号：TU473.1[建筑科学—结构工程]