桩端后压浆对钻孔灌注桩侧摩阻力的增强作用  

Enhancement effect of base post-grouting on shaft resistance of bored piles

作　　者：刘红艳[1] 万志辉[2] LIU Hongyan;WAN Zhihui(School of Civil and Architecture Engineering,Liaoning University of Technology,Jinzhou 121001,China;School of Civil Engineering,Southeast University,Nanjing 211189,China)

机构地区：[1]辽宁工业大学土木建筑工程学院,辽宁锦州121001 [2]东南大学土木工程学院,江苏南京211189

出　　处：《武汉大学学报（工学版）》2020年第12期1078-1084,共7页Engineering Journal of Wuhan University

基　　金：鲁能集团有限公司科技项目(编号:SGDC0000KXJS1900137)。

摘　　要：为研究桩端后压浆对钻孔灌注桩侧摩阻力的影响,基于3个现场静载试验,通过对桩端持力层为粉土层、砂土层及砾石层3种类型土层的未压浆桩与压浆桩的试验结果进行对比分析,阐述了桩端后压浆增强的桩端土体强度对桩侧摩阻力的强化作用,并从理论上揭示了桩端后压浆对桩侧摩阻力的增强作用机理。结果表明,桩端后压浆增强的桩端土体强度不但可以控制桩端沉降量,还能提高桩身总侧摩阻力,特别是桩端附近的侧摩阻力;桩端后压浆对桩侧摩阻力的增强作用效果与桩端压浆加固效果有着显著关系。研究结果可为进一步挖掘后压浆桩承载潜能、优化桩基设计提供新思路。To study the effect of post-grouting at the pile tip on the shaft resistance of cast-in-place bored piles,based on three field static load tests of non-grouted and grouted piles in the soil layers of silt,sand and gravel were conducted,and the test results of ungrouted and grouted piles in the three types of soil layers of silt,sand and gravel were analyzed.The strengthening effect of the improvement of the soil strength at the pile end reinforced by due to tip post-grouting on the mobilization of shaft resistance was studied,and the strengthening mechanism of the shaft resistance of the pile by tip post-grouting was revealed theoretically.The results show that the soil strength at the pile end enhanced by tip post-grouting can not only control the settlement of the pile end,but also improve the total shaft resistance of the pile,especially the shaft resistance near the pile end.Moreover,the strengthening effect of tip post-grouting on the shaft resistance of pile has a significant relationship with the effect of grouting reinforcement at the pile end.The research results can provide a new idea for further exploring the bearing potential of post-grouting pile and optimizing the design of pile foundation.

关 键 词：钻孔灌注桩 桩端后压浆 桩侧摩阻力 静载试验 强化效应 

分 类 号：TU473[建筑科学—结构工程]