后压浆对超长钻孔灌注桩承载特征的影响研究  

RESEARCH ON INFLUENCE OF POST GROUTING ON BEARING CAPACITY CHARACTERISTICS OF SUPER-LONG 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 210096, 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,南京210096

出　　处：《工业建筑》2018年第3期91-96,共6页Industrial Construction

摘　　要：后压浆技术能有效地消除钻孔灌注桩的施工缺陷,同时能有效地改善桩基的承载性状。基于后压浆超长钻孔抗压桩和抗拔桩的现场静载荷试验,研究后压浆超长钻孔灌注桩的抗压和抗拔承载特性,分析后压浆桩在加载初期桩顶刚度偏低于未压浆桩的异变现象。结果表明：后压浆技术对提高桩基成桩质量的稳定性具有很好的效果,且可显著提高基桩极限承载力;但在正常使用极限状态下部分超长钻孔灌桩沉降性能反而劣化,反映了后压浆技术的强化效应存在不稳定性。Post-grouting technique can effectively eliminate the construction defects of bored piles,and can effectively improve the bearing characteristics of bored piles. Based on field static load tests,the bearing characteristics of super-long compressive and uplift bored piles with post-grouting were studied. The abnormal phenomena which the pile top stiffness of grouted pile at the initial loading stage was lower than that of conventional pile was analyzed. The results showed that post-grouting technique had a significantly effect on improving the stability of pile quality and ultimate bearing capacity. The settlements of some super-long bored piles with post-grouting under serviceability limit state were larger than that without post-grouting,which reflected the instability of the strengthening effect.

关 键 词：超长钻孔灌注桩 后压浆技术 静载荷试验 桩顶沉降 异变现象 

分 类 号：TU473.1[建筑科学—结构工程]