沪蓉西高速公路贺家坪段顺层边坡结构稳定性分析

Structure Stability Analysis for Consequent Slope of Hejiaping in Hurongxi Highway

顺层边坡是工程实践中经常遇到也是较容易产生破坏的一类边坡,其失稳问题一直是工程界极为瞩目和急需解决的问题之一。从地质力学角度分析了顺层边坡的形成机制,抽象出了顺层边坡溃屈破坏的力学模型。利用结构力学的基本理论,推导出了相应的计算公式,并利用文中的理论方法,分析了沪蓉西高速公路贺家坪段顺层边坡(桩号k63-k64)的稳定性,结果与实际情况吻合较好。

Consequent slope is one of the most common kinds in engineering; the stability-losing of it is the most urgent problem. Based on the geological background and mechanism, mechanical model of buckling failure for the consequent slope is given in this paper. According to the stability theory for elastic plane and the structure mechanics, the utmost length lcr=3[（2π^2Eh^2/3γsinaα）的平方根]and the factor of safety calculation formula η=lcr/l of slope have been deduced. A case of Hejiaping Consequent slope in Hurongxi Highway is analyzed using the method deduced in the paper finally, the research indicates that the factor of safety （FOS） decreases with the increasing of slope angle （α）. Especially when α is less than 20°, the FOS declines sharply which demonstrates sensitivity of FOS to the transformation of slope angle. But with the increasing of the slip bedding thickness, FOS increases, and the relationship between them is approximate direct proportion variety. Mean while, the factor of safety enhances when elasticity module increases, however the influence isnt obvious. The result is in agreement with the practical states.