节理岩体边坡概率损伤演化规律研究

STUDY ON PROBABILITY DAMAGE EVOLUTIONARY RULE OF JOINTED ROCK MASS SLOPE

露天矿边坡岩体是含有大量空间上随机分布裂隙的三维损伤体,岩体的强度和内部裂隙分布在空间上均具有随机性,岩体损伤是一种概率损伤。应用三维节理网络模拟技术建立节理岩体损伤张量及概率分布规律的计算方法,综合应用Rosenblueth原理、损伤断裂力学与数值模拟等理论与技术,建立三维节理岩体概率损伤演化的耦合分析程序,通过对鞍钢眼前山露天铁矿南帮边坡岩体随采场逐渐下降过程中概率损伤演化规律的数值模拟,计算得出边坡岩体在不同开采阶段的损伤张量的均值与标准差,揭示节理岩体损伤张量在露天矿开采的空间和时间上的动态变化规律,建立露天矿不同开采阶段的边坡岩体三维随机损伤场,为评价露天矿边坡可靠性的动态变化规律奠定基础。

The rock mass of open mine slope is the 3D damage mass, which contains a large amount of joints distributing randomly in space. Because both its strength and joints distribution are random, the damage of rock mass is a kind of probability damage. According to the definition of damage tensor of jointed rock mass and simulation of 3D joint network, the analysis approach and program of the damage tensor and the probability distribution rule of jointed rock mass are put forward. Based on the Rosenblueth principle, the theories of effective stress in damage mechanics and fracture mechanics, FLAC3D numerical simulation and 3D joint network simulation, etc., the coupling analysis technique of the probability damage evolution in 3D jointed rock mass has been established. It organically combines the damage theory, fracture analysis of jointed rock mass and numerical simulation of slope excavation, and provides a practical approach for the probability damage evolution rule of jointed rock mass. The formation of slope is a long-term process during mining. With the development of mining engineering, damage of jointed rock mass is progressively accumulated. The results have been proved during the excavation of the south slope of Yanqianshan Open Iron Mine. The assessment and working process of the probability damage and the evolution are systematically studied with the excavation of the rock slope. The spatial distribution and evolution of the damage rules of the rock slope are quantitatively shown. 3D random damage fields of the rock mass in different excavation stages are established by applying Rosenblueth principle and numerical simulation of the damage evolution. The damage tensor, the mean and the variation of damage degree are calculated. The dynamic laws of stability and reliability of open pit mine will be well studied.