一个改进的土坡安全系数表达式

An Improved Expression of Safety Factor for Soil Slope

从黏性土的剪切强度出发,认为将土的剪切强度表达式除以安全系数进行折减,所得表达式与库仑准则相矛盾。为此,仅对土的剪切强度表达式中的摩阻力部分进行折减,得到满足库仑准则的黏性土的强度折减式,推导出了新的土坡安全系数表达式,用该表达式计算了17例土坡安全系数。结果表明,计算出的土坡安全系数值比目前教材上的值小0.23%~24.07%,对工程而言,偏于安全,新的土坡安全系数表达式更合理。

Based on the shear strength of cohesive soil,the shear strength expression of soil divided by the safety factor is incontradiction with the Coulomb criterion.Only the frictional resistance of the shear strength expression is reduced in the improved expression,thus constructing a new strength reduction formula for cohesive soil which conforms to the Coulomb criterion.In this way,a new slope stability factor expression is derived.Then the expression is used to calculate the safety factors of seventeen soil slopes.The results show that the values of safety factor of soil slopes calculated with the new expression are 0.22%~25.05%smaller than those in the current textbooks,which is safer for engineering projects.In comparison,the proposed new safety factor expression of soil slope is more reasonable.This improved expression has reference value for related engineering analysis.