深层高压注浆加固古滑坡滑动带试验及效果分析

通过深层高压注浆法加固混碎石黏土古滑坡滑动带的成功工程实例,结合各种检测手段及有限元弹塑性分析,阐述对混碎石黏土古滑坡滑带土实施深层高压注浆加固的机制；测试和分析了滑动带压力注浆前后物理力学参数的变化特征；计算了注浆前后滑坡的剩余下滑力及安全系数。电镜观测表明，水泥浆液对于滑动带岩土体的充填置换率可达到5%～10%；土工试验结果显示，滑动带土体黏聚力由20.20 kPa提高到39.54 kPa，内摩擦角由16°升高到21.30°；声波CT扫描试验表明，滑动带土体的声波波速增长约为31%。有限元弹塑性分析计算表明，滑坡由注浆前的不稳定状态变为注浆后的基本稳定状态，边坡剩余下滑力大幅减小，为支挡结构设计提供了优化依据。试验及计算分析结果表明，高压注浆法用于加固滑动带岩土体是可行的，经注浆加固后的滑动带岩土体的力学性能得到了明显改善，边坡安全性得到了提高。

Test and analysis of effect of applying deep high pressure grouting method to stabilizing sliding zone of ancient debris landslide

Based on successful reinforcement projects of the sliding zone of the ancient debris landslide with applying deep high pressure grouting method,and combined with various detection measures and elastoplastic finite element analysis,the mechanism of deep high pressure grouting to reinforce sliding zone,physico-mechanical parameters of the soil in sliding zone before and after grouting,the remnant sliding force and safety factors of the landslide have been studied.Electron microscopy experiments show that,The filling replacement rate of cement slurry to rock and soil in sliding zone is 5%～10%.The soil tests results indicate that the soil cohesion increase from 20.20 kPa to 39.54 kPa and its internal friction angle from 16° to 21.30°.The sound wave CT scanning experiments show that the sound wave velocity of the soil in the sliding zone increases about 31%.The finite element analysis show that pressure grouting could make the unstable landslide go into the basic stable state and the remnant sliding force reduces a lot.These can provide optimization basis for retaining structure design.Tests and calculation results show that high pressure grouting method for enhancing the rock and soil in sliding zone is feasibility.The mechanical performance of the rock and soil in sliding zone has been significantly improved and the safety of the slope has been enhanced.