块裂反倾巨厚层状岩质边坡变形破坏颗粒流模拟及稳定性分析  

Simulation of deformation and failure for blocky anti-dip thick-layered rock slopes using particle flow code and analysis on its stability

作　　者：岑夺丰[1] 黄达[1,2] 黄润秋[3] 

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]重庆大学煤矿灾害动力学与控制国家重点实验室,重庆400044 [3]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059

出　　处：《中南大学学报（自然科学版）》2016年第3期984-993,共10页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(41472245;41130745);重庆市研究生科研创新资助项目(CYB14018)~~

摘　　要：为了研究块裂反倾巨厚层状岩质边坡破坏机制及稳定性,基于PFC2D平行黏结模型和持续增加重力加速度方法,研究边坡破坏模式、应力-变形及能量耗散演化,并用临界重力加速度量化研究其稳定性。研究结果表明:边坡破坏模式主要有滑移、倾倒和溃屈破坏3类且随岩层倾角增大而逐渐转变;随岩块两相邻边长比l/h增大,边坡越倾向于发生倾倒破坏;滑移和倾倒破坏模式从坡脚向上坡体应力逐步达到峰值并峰后跌落,具有渐进破坏特征。而溃屈破坏模式坡体各部位应力呈"捆绑"型波动性塑性流动状态,具有大面积剧烈整体性破坏特征;随着岩层倾角(45°,60°,75°)增大,边坡临界重力加速度先减小再增大,稳定性在60°时最弱。边坡稳定性随岩块增大而增强,并主要受层间裂隙间距控制。In order to study the failure mechanism and stability for blocky anti-dip thick-layered rock slopes, based on the parallel bonded model of PFC2 D and the method of increasing the gravitational acceleration, the slope failure mode, evolution of stress-deformation and energy dissipation were researched, and the stability was quantitatively analyzed according to the critical gravitational acceleration. The results show that the slopes show three failure modes, i.e. sliding, topping and bulking failure, which are transformational with the increase of dip angle of rock stratum. Topping failure is much more likely to happen with the increase of l/h, where l and h are the lengths of two adjacent sides of the rock blocks. The stress in slope gradually reaches the peak state and then drops from bottom to top for sliding and topping failure modes, which reflects the progressive failure characteristics. However, the stress in each part of the slope shows the bundle-like plastic flow state for bulking failure mode which has large area and dramatical integrity failure characteristics. The critical gravitational acceleration decreases first, then increases with the increase of dip angle of rock stratum（45°, 60°, 75°） and the stability is the weakest one when the dip angle of rock stratum is 60°. Slope stability increases with the increase of rock block size, and it is mainly controlled by spacing of interlaminar fractures.

关 键 词：块裂反倾边坡 变形破坏 稳定性 演化 颗粒流 

分 类 号：TU457[建筑科学—岩土工程]