自平衡高压注浆与普通注浆土钉墙稳定性对比分析

摘要

A self balanced high-pressure grouting steel pipe soil nail is researched,and based on the study of mechanical properties for self balanced pressure grouting pipe soil nailing,the force of grouting in soil nailing in the direction and mechanism of high pressure grouting are analyzed.The results show that the tensile properties of the self balanced high pressure grouting soil nail are better than that of the ordinary grouting soil nail.Through the simulation of engineering calculation with self balance high-pressure grouting soil nailing wall and ordinary grouting soil nailing wall,the difference of overall,sliding and overturning stability safety coefficients between self balanced high pressure grouting and ordinary grouting soil nailing wall with the same design parameters are analyzed.The analysis results show that,when excavating the bottom of the foundation pit,the radius of the most unfavorable slip surface of the high-pressure grouting soil nailing wall is obviously larger than that of the ordinary grouting soil nail,which is more conducive to the stability of the sliding body.Under the same conditions,the safety factor of high pressure grouting soil nailing wall is obviously higher than that of ordinary soil nailing wall,but there is no difference between sliding and overturning stability safety coefficients.Compared with ordinary grouting soil nailing wall,high-pressure grouting soil nailing wall has no effect on anti slide and overturning safety.%研发了自平衡高压注浆钢管土钉,并对其受力特性进行了研究,分析了注浆浆液在土钉中的传力特点及实现高压注浆的机理,发现自平衡高压注浆桩抗拉性能明显优于普通注浆土钉.通过模拟工程分别对自平衡高压注浆土钉墙与普通注浆土钉墙进行计算,分析相同设计参数下,两种土钉墙整体圆弧滑动稳定性安全系数、抗滑移、抗倾覆稳定安全系数的差异.分析结果表明,在挖到基坑底部时,高压注浆土钉墙最不利滑动面半径明显大于普通注浆土钉,更有利于滑动体的稳定.相同工况下高压注浆土钉的圆弧滑动稳定安全系数要明显高于普通土钉,但对于抗滑稳定和抗倾覆稳定性两者则没有差异,高压注浆土钉墙相比普通注浆土钉墙在抗滑和抗倾覆安全性上也没有提高作用.