【摘要】 依托实际工程,针对黄土地区复杂地质条件,特别是含淤泥卵石持力层既有桩后注浆技术应用经验欠缺的问题,通过现场试验与MIDAS-GTS数值模拟,分析了依托工程原灌注桩承载力未达到设计要求的原因,探索适用于既有桩的后注浆技术参数与工艺,解决了在既有桩桩身成孔时钻机垂直度不好保证的难题。试验显示,该工况下灌注桩注浆后承载力比注浆前平均提高幅度为81.6%,为上述地质条件灌注桩后注浆技术提供了应用经验与设计依据。通过数值分析,探讨了后注浆灌注桩受力时桩身及桩周土体应力分布与传播规律,总结得出"岩土体切向削弱现象"。更多还原

【Abstract】 Based on the actual project,aiming at complex geological conditions in loess areas,especially the shortcomings in the application of post grouting technique for the existing pile in scree bearing layer with sludge,through field test and GTS-MIDAS numerical simulation,it analyzed the reason of bearing capacity of original pile in support project cannot meet the design specification,exploring the parameters and technology of post grouting technology for existing piles,solving the problems of the drill is not good to ensure the verticality in the pile. Experimental evaluation showed that bearing capacity of after grouting pile was enhanced with an average range of 81.6%,it provided the experience and design basis for the application of grouting technology in the post grouting pile. The stress distribution and propagation law of the pile body and soil around pile in the post grouting pile were discussed,and the conclusion was drawn that the phenomenon of rock and soil shear weakening by numerical analysis.更多还原