二次注浆微型桩水平承载力试验与数值模拟研究  

Experiment and Numerical Simulation Analysis on Horizontal Bearing Capacity Secondary Grouting Micro-piles

作　　者：郭亮[1] 周峰[1] 李俊才[1] 刘壮志[1] 苏荣臻[2] 

机构地区：[1]南京工业大学土木工程学院,南京210009 [2]中国电力科学研究院,北京102401

出　　处：《建筑科学》2011年第3期78-83,共6页Building Science

摘　　要：微型灌注桩施工简便、竖向承载力高、经济环保,具有良好的适用性。但在某些特殊工程中当微型灌注桩承受水平荷载时,由于受桩径和施工工艺的限制,往往不能满足水平承载力设计要求,从而很大程度上限制了微型灌注桩的进一步推广应用。通过不同施工工艺微型灌注桩的现场水平荷载试验及数值模拟,研究微型桩桩周二次注浆施工工艺对单桩水平承载力提高的影响。由现场试验研究二次注浆施工工艺对微型灌注桩单桩水平荷载-位移曲线形式、临界荷载、极限荷载、桩周土抗力系数的比例系数m值的影响;由数值模拟对比分析不同注浆量及注浆范围对单桩水平承载力的影响,进而得出桩土最优刚度比和最佳注浆深度。最后初步探讨了微型桩桩周二次注浆施工工艺提高单桩水平承载力的机理。By the horizontal load test and numerical simulation of micro-piles in different construction technologies,the major factors influencing the horizontal beating capacity of the micro-piles were studied.The influence factors such as secondary grouting process functions in horizontal load-displacement curve form,the critical load,ultimate load,and the horizontal resistance forces proportionality coefficient（m） of the soil around pile were investigated.In addition,the influence of different grouting volumes and grouting ranges on the horizontal bearing capacity of single pile was analyzed by numerical simulation.Results show that secondary grouting process can improve the deformation and the behavior of micro-piles affected by the horizontal load and enhance horizontal bearing capacity of micro-piles.The horizontal resistance force proportionality coefficient（m） of the soil around pile should choose the maximum value provided by the standard during the design of micro-piles.The pile-soil optimal stiffness ratio is 100：1 and the best injected depth is 4D.Finally,the mechanism improving the horizontal bearing capacity of single pile by secondary grouting process around micro-piles was discussed.

关 键 词：微型灌注桩 二次注浆 水平承载力 试验研究 数值模拟 

分 类 号：TU473.14[建筑科学—结构工程]