运用时程分析方法,分析小湾饮水沟堆积体边坡在爆破荷载作用下的动力稳定性。分析中考虑了爆振波在滑体、滑床中的传播规律以及与滑动面张开、滑移等性态的动态耦合过程。从滑动面张开、闭合状态及坡体的位移场来看,边坡在爆破开挖下不会出现整体滑动;但在距爆区20m的质点的峰值振动速度超过边坡的安全振速,因而在近爆区局部边坡可能会出现松动掉块等局部性破坏。
The dynamic stability of a slope in Xiaowan hydropower station is studied under the blasting load with the dynamic FEM. By means of a special dynamic interface contact element, the coupling behavior of the blast wave propagation property and the dynamic response of the contact element are also considered in the analysis. Numerical results indicates~ (1) the stability of the whole slope can be ensured even under the largest blast loading conditions; (2) the local instability could happen at the vicinity of the blast holes because the particle velocities in this area are much larger than the allowable velocity; (3) interface elements on the sliding surface of the slope are most ooened by the blast waves, which might be a dominant factor controlling the whole stability of the slope.