考虑岩土体剪胀特性的边坡稳定性分析*

为考虑岩土体剪胀特性对边坡稳定性的影响，基于非关联流动法则，利用等效内摩擦角的概念对原抗剪强度参数进行修正，以修正后的等效参数c*，φ*探讨剪胀角对岩土体强度的影响，结合传统强度折减法以及基于临界曲线的双系数折减法，求解基于修正后等效参数计算的边坡安全系数，并给出安全系数的取值方法。结果表明:采用等效参数来考虑剪胀角的影响是可行的；随剪胀角的增大安全系数增大，且增长速度变缓，剪胀角在0~25°范围内对安全系数的影响显著，在实际工程计算中需要考虑剪胀角对边坡稳定性的影响；基于临界曲线的双系数折减法可较为直观地体现出剪胀角的影响程度，在研究剪胀角对边坡稳定性的影响时可采用此方法进行分析。

Analysis on slope stability considering shear dilatation characteristics of rock and soil mass

In order to consider the influence of shear dilatation characteristics of rock and soil mass on the slope stability,based on the law of non correlated flow,the concept of equivalent internal friction angle was utilized to modify the original shear strength parameters,and the modified equivalent parameters c* and φ* were used to reflect the influence of shear dilatation angle on the strength of rock and soil mass.Combining with the traditional strength reduction method and the double factor reduction method based on the critical curve,the slope safety factor calculated with the modified equivalent parameters was solved,and the valuing method of the safety factor was given.The results showed that considering the influence of shear dilatation angle by using the equivalent parameters was feasible.With the increase of the shear dilatation angle,the safety factor increased,and the growth rate decreased.The shear dilatation angle had significant influence on the safety factor in the range of 0~25°.In the actual engineering calculation,it was necessary to consider the influences of shear dilatation angle on the slope stability.The double factor reduction method based on the critical curve could reflect the degree of influence of the shear dilatation angle more intuitively.This method can be used to analyze the influence of shear dilatation angle on the slope stability.