凹边坡参数对边坡稳定性的影响

Effects of Concave Slope Parameters on Slope Stability

抽象出凹边坡的几何模型,采用量纲分析的方法,给出凹边坡几何参数和物理力学参数对边坡稳定系数的影响通式.在FLAC定义的边坡稳定系数意义下,经过数万次计算,采用二次回归的方法,确定了通式中的影响指数,形成经验公式.结果表明,受Mohr-Coulomb和拉应力两个强度准则控制的材料,形成的凹边坡的稳定性受无量纲粘聚力、边坡角、内摩擦角的控制.凹形边坡有利于边坡的稳定,边坡稳定性与岩土的抗拉强度关系不大.这一稳定系数公式对于形状规则均匀性好且符合Mohr-Coulomb破坏准则的凹边坡可以给出精度高的估计.对于其它边坡的稳定性评价还需要做有针对性的工作.

Geometrical model of concave slope was initially formulated. By employing dimensional analysis, formula of slope stability factors was expressed by geometrical and physical parameters. Thousands of computations on concave slope stability were carried out. The results were used to determine the parameters in the formula. It turns out that, the stability of concave slope is governed by four dimensionless parameters, namely slope angle, internal friction angle, internal cohesion force divided by the product of slope height and specific gravity, ratio of radius of slope bottom curve and slope height. The tension strength of slope material has little influence on the stability of concave slope. The current formula of stability factors is able to accurately predict the stability of slopes that are in regular shape and in accordance with Mohr-Coulomb criterion. Future work related to other types of slopes still need to be done.