基于量化GSI系统对地下岩体力学参数的估算

Estimation on Mechanical Parameters of Subsurface Rock Mass Based on Quantitative GSI System

地下岩体力学参数的准确获取可以为破碎岩体支护设计、采矿方法优化提供一定数据支撑,对保护井下作业人员安全起着重要作用。为准确、便捷获得地下岩体力学参数,采用岩体结构等级SR、岩体结构面等级SCR以及岩体完整性系数Kv 3个指标,通过多指标交集定量化获取GSI值,并结合地质强度指标GSI与扰动参数D之间存在的数理关系,量化扰动参数D,并应用Hoek-Brown强度准则确定岩体力学参数。将实际地质调查结果与室内岩石力学试验相结合,估算某地下铁矿岩体力学性能指标,发现矿体力学性能明显弱于围岩约60%,表明需加强进路巷道以及矿岩边界处的支护强度,该估算方法对地下岩体稳定性优化设计具有重要的指导意义。

Accurately obtaining the mechanical parameters of underground rock mass can provide certain data support for the support design of broken rock mass and optimization of mining methods,which plays an important role in protecting the safety of underground workers.Therefore,in order to accurately and conveniently obtain the mechanical parameters of the underground rock mass,three indices,namely the rock mass structural grade SR,the rock mass structural surface grade SCR and the rock mass integrity factor Kv,are used to obtain the GSI value by the intersection of several indices,and the disturbance parameter D is quantified by combining the mathematical correlation between the GSI and the disturbance parameter D.The mechanical parameters of the rock mass are obtained by the modified Hoek-Brown strength criterion;Combining the actual geological survey results with indoor rock mechanics tests,the mechanical properties of the rock mass of an underground iron ore mine were estimated,and it was found that the mechanical properties of the ore body were significantly weaker than that of the surrounding rock by about 60%,indicating that the support strength of the access roadway as well as that of the ore rock boundaries needed to be strengthened,and the estimation method was of great significance in guiding the optimal design of the stability of the underground rock mass.