双层结构岩质边坡的滑带扰动厚度计算方法研究

双层结构岩质边坡进行稳定性评价通常可以实现,但合理确定滑体引起的滑带扰动厚度却比较困难。根据能量法原理,可以推导得出上部硬岩滑体的能量法稳定系数上限解计算公式。进一步按照能量平衡方程,综合考虑滑体、滑带在重力作用下所做的外力功率,以及滑带产生的内能耗散,推导得到了计算滑带扰动厚度的解析公式。在分析典型算例基础上,提出了滑带扰动分带的概念,并将滑带按照扰动程度分为剧扰动带、强扰动带、中等扰动带、弱扰动带和微扰动带。对于双层结构的岩质边坡进行加固治理时,其治理的深度范围应该大于微扰动带的底面。

METHOD FOR CALCULATING DISTURBED THICKNESS OF SLIDE ZONE IN ROCK SLOPE WITH TWO-LAYER STRUCTURE

It is very difficult to calculate the disturbed thickness of slide zone in rock slopes with two-layer structure, although stability analysis of the rock slopes can be easily carried out. According to the theory of energy method, the formula of safety factor with meaning of upper bound solution is deduced in the paper. Furthermore, the formula of disturbed thickness is also derived when both the external work done by self weight of the slope and internal energy dissipation caused by slide zone are all taken into consideration. On the basis of analyzing a typical case, the paper puts forward a new concept of disturbed zonage about slide zone, and divides the disturbed thickness into five zones according to the degree of disturbance. They are the intensely, strongly, moderately , weakly and slightly disturbed zones. The depth range of reinforcing treatment for a two-layered rock slope should exceed the bottom of the slightly disturbed zone.