Mechanical parameters of rock mass in mining engineering feature the characteristics of spatial variability and time decay, and it plays an important role in the slope stability analysis. The mechanical behaviour of rock engineering in low in-situ stress condition is highly affected by the rock mass quality. In this paper, the distribution of geological strength index (GSI) was obtained by geostatistics-based methods to determine the spatial variability of mechanical parameters. Moreover, mechanical parameters of rock masses in open-pit mine are deteriorating continuously in the mining process. A damage model using microseism (MS) data was proposed to describe the time decay of mechanical parameters. Additionally, the dynamic programming method was used to search the rough critical slip surface and factor of safety considering the heterogeneous mechanical parameters. An example was further employed to demonstrate these proposed methods in the Dagushan open-pit mine. The results indicated that incorporation of spatial variability and time decay into mechanical parameters leaded to a fundamental change in the slope stability. Our study helps to provide detailed mechanical parameters, which contribute to a more reasonable explanation as well as provide governance measures for the rock landslides.

中文翻译：

---

岩体力学参数的空间变异性和时间衰减：大孤山露天矿滑坡研究

采矿工程岩体力学参数具有空间可变性和时间衰减的特点，在边坡稳定性分析中具有重要作用。岩石工程在低地应力条件下的力学行为受岩体质量的影响很大。本文通过基于地质统计学的方法获得地质强度指数（GSI）的分布，以确定力学参数的空间变异性。此外，露天矿岩体的力学参数在开采过程中不断恶化。提出了一种使用微震 (MS) 数据的损伤模型来描述机械参数的时间衰减。此外，考虑异构力学参数，采用动态规划方法搜索粗糙临界滑移面和安全系数。进一步通过一个例子在大孤山露天矿中证明了这些建议的方法。结果表明，将空间变异性和时间衰减纳入力学参数导致边坡稳定性发生根本变化。我们的研究有助于提供详细的力学参数，有助于更合理地解释岩石滑坡并提供治理措施。结果表明，将空间变异性和时间衰减纳入力学参数导致边坡稳定性发生根本变化。我们的研究有助于提供详细的力学参数，有助于更合理地解释岩石滑坡并提供治理措施。结果表明，将空间变异性和时间衰减纳入力学参数导致边坡稳定性发生根本变化。我们的研究有助于提供详细的力学参数，有助于更合理地解释岩石滑坡并提供治理措施。