顺倾层状岩质边坡滑移-溃屈破坏力学分析

Mechanical Analysis of Slip-Buckling Failure of the ConsequentBedded Rock Slope

顺倾层状岩质边坡是工程建设中经常遇到的一种边坡类型,在岩层自重、地震力及静水压力作用下常常发生滑移-溃屈破坏.基于弹性压杆理论和能量法建立了顺倾层状岩质边坡的滑移-溃屈破坏力学模型并进行了力学分析,推导出在由岩层自重、地震力及静水压力联合作用下顺倾层状岩质边坡发生滑移-溃屈破坏时的弯曲段长度条件方程.以霸王山滑坡为实例对该条件方程的合理性进行了验证,结果显示所计算的结果与实际情况较为一致,证明了该条件方程的合理性.通过参数敏感性分析发现:随着静水水头高度、岩层厚度、岩石弹性模量及层间摩擦强度的增加,顺倾层状岩质边坡发生滑移-溃屈破坏时的弯曲段长度随之增加;随着岩石重度、岩层倾角及水平地震系数的增加,顺倾层状岩质边坡发生滑移-溃屈破坏时的弯曲段长度随之减小.

The consequent bedded rock slope is a type of slope that is often encountered in engineering construction,and slip-buckling failure often occurs in this kind of slope under the action of the self-weight of rock stratum,seismic load and hydrostatic pressure.On basis of the elastic pressure bar theory and energy method,the slip-buckling failure mechanical model for the consequent bedded rock slope is established and the mechanical analysis is carried out.The conditional equation of the bending segment length is deduced when the slip-buckling failure occurs in the consequent bedded rock slope under the combination action of the self-weight of rock stratum,seismic load and hydrostatic pressure.Bawangshan landslide is taken as an example to verify the rationality of the conditional equation.The results show that the calculation results are in good agreement with the actual situation,which proves the rationality of the conditional equation.Through parameter sensitivity analysis,it is found that with the increase of hydrostatic head height,rock layer thickness,rock elastic modulus and friction strength between the rock layers,the length of bending section of the consequent bedded rock slope increases when sliding-buckling failure occurs.With the increase of rock gravitational load intensity,rock layer dip angle and horizontal seismic coefficient,the length of bending section of the consequent bedded rock slope decreases when sliding-buckling failure occurs.