岩土工程界广泛应用BQ法进行围岩稳定性分级,在分级过程中考虑地应力、结构面和地下水因素3个修正指标进行修正,而地下水影响因素修正系数和结构面影响的修正系数这2个指标在确定过程中存在分歧,提出采用加权平均法进行修正确定,给出修正模型和方法,利用修正后的[BQ]′值进行巷道围岩稳定性分级,为巷道经济合理支护提供依据。分级结果与现场实际情况一致,证明修正方法合适,能提高BQ法围岩稳定性分级的准确性。
The BQ method are widely applied for stability classification of surrounding rock mass in rock engineering field ,three indexes included initial geostress ,structural plane and groundwater were used to revise the BQ value in the course of classification ,however ,there two indexes ,modified coefficient of groundwater and modified coefficient of structural plane ,are differences exist in selection .The score calculation method revised with weighted average is proposed ,which could provide basic data for economic and rational tunnel support by stability classification with modified [BQ]′value .The results were agree with the actual situation in the mine ,which proved the method was accurate ,and could improve the accuracy of BQ method for stability classification of surrounding rock .