地质勘察时顺层路堑边坡稳定性的初步判定方法

Preliminary Judgment Method for Stability of Bedding Cutting Slope in Geological Survey

基于对顺层边坡稳定性影响因素的研究成果,从路堑边坡岩层走向与线路夹角、不同岩性岩层结构面综合内摩擦角、岩层倾角、岩层厚度等方面对地质勘察时顺层路堑边坡稳定性的初步判定方法进行探讨。结果表明:岩层走向与线路夹角是路堑边坡稳定性的首要判定条件;对高度不大于30 m的边坡,岩层结构面倾角大于其综合内摩擦角是判定路堑边坡稳定性的条件之一;岩层倾角在10°~85°时路堑边坡受到破坏,大于85°时破坏模式转变为倾倒破坏。对顺层路堑边坡稳定性进行初步判定后须经设计检算确定支挡防护措施。

Based on the research results of the factors affecting the stability of bedding slope,the preliminary judgment methods for the stability of bedding cutting slope in geological survey were discussed from the aspects of the angle between rock stratum direction of cutting slope and railway line,the equivalent friction angle of rock stratum structural plane with different lithological characters,the strata inclination and the strata thickness. The research results showthat the angle between the rock stratum direction and railway line is the capital judgment for the stability of the cutting slope which height is no more than 30 m. O ne judgment condition for the stability of cutting slope is that the inclination of rock stratum structural plane is larger than its equivalent friction angle,the cutting slope is destroyed when the strata inclination is between 10°~ 85°,and the failure mode of the cutting slope will change to toppling failure when the strata inclination is greater than 85°.The support protection measures must be determined through design checking after preliminary judgment for the stability of bedding cutting slope.