崩塌体稳定性检算方法优化研究

Optimizing of calculation methods in rockfall stability

针对现有崩塌体稳定性检算方法存在的问题,对倾倒式和错断式两种崩塌体的稳定性检算方法进行了修正,指出倾倒式破坏只考虑底部与稳定岩体断开的情况是不全面的;错断式破坏的破坏面确定不能按最大剪应力原理确定,而应遵循摩尔 库仑准则。建立了相应修正的稳定性检算方法,通过检算实例与原方法比较发现,对倾倒式检算,如果底部连接时,原方法考虑过于安全,不适用于底部连接的情况;对错断式检算,原检算方法偏于不安全,特别是当崩塌体底部岩体节理裂隙发育或有不利结构面存在时。

For being some questions on the calculation methods in rockfall stability, two methods, overthrown and leap rockfall, are modified. The authors think it is not suitable for overthrown rockfall to only consider the rock mass parting from stable rock mass. To determinate failure face of leap must use MohrColumn criterion. The modified calculation methods for safety factors of overthrown and leap failure are set up and a calculation example is given. Comparing with the old method, it is found that old method for overthrown failure is too conservative to the situation that overthrown rock mass connects with stable rock mass, but for leap failure is not safe, specially, when lower rock mass of leap exists a large amount of joints or creaks or a harmful discontinuous surface.