多次注浆微型桩水平承载力试验与数值模拟分析  

Numerical simulation analysis and horizontal bearing capacity test of multiple 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,江苏南京210009 [2]中国电力科学研究院,北京102401

出　　处：《南京工业大学学报（自然科学版）》2010年第6期64-70,共7页Journal of Nanjing Tech University(Natural Science Edition)

摘　　要：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,研究微型灌注单桩水平承载力的主要影响因素.试验考察多次注浆工艺对微型灌注单桩水平荷载-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)等的影响.数值模拟对比分析注浆量及注浆范围对单桩水平承载力的影响程度.结果表明:多次注浆工艺可明显改善水平荷载作用下微型灌注桩的变形及工作性状,有效提高微型单桩的水平承载力;在对多次注浆微型桩进行水平承载力设计时,m应取规范所给的最大值;桩土最优刚度比为100∶1,最佳注浆深度为4D.最后初步探讨了微型桩桩周多次注浆施工工艺提高单桩水平承载力的机制.By the horizontal load test and numerical simulation of micro-piles in different construction processes,the major factor for influencing the horizontal bearing capacity of the micro-piles was studied.The influence factors such as multiple grouting process functions in horizontal load-displacement curve form,the critical load,ultimate load,and the horizontal resist forces proportionality coefficient（m） of the soil around pile were investigated.In addition,the influence degree of different grouting amounts and grouting ranges to the horizontal bearing capacity of single pile were analyzed by numerical simulation.Results indicate that multiple grouting process can improve the distortion and the behaviour of micro-piles affected by the horizontal load and enhance horizontal bearing capacity of micro-piles.The horizontal resist force proportionality coefficient（m） of the soil around pile should choose the maximal value provided by the standard during the design of micro-pile.By tests the pile-soil optimalizing stiffness ratio is 100∶1 and the best injected depth is 4D.Finally,the mechanism for enhancing the single pile horizontal bearing capacity by micro-pile multiple grouting process was discussed.

关 键 词：微型灌注桩 多次注浆 水平承载力 数值模拟 

分 类 号：TU443[建筑科学—岩土工程]