关键词: 岩体质量分类, 变权重, 区间模糊, 隶属函数, 贴近度

Abstract: To improve the existing rock mass classification methods, we proposed a variable weight interval fuzzy evaluation method for rock mass quality rating. Firstly, the membership functions were finely established for indexes in RMR classification system, including rock uniaxial compressive strength, RQD, joint spacing, joint condition and groundwater condition. Besides, the normalized closeness degree was used to replace the membership degree to overcome the existing error when some index values are fuzzy due to distribution interval. Further, the variable weight method was applied to emphasize the importance of the inferiority index in the rock mass grading decision, making the evaluation result more accordant with the practical demand. For verification, the new method was applied to a practical example, which showed the proposed method was more applicable in comparison with the RMR method.

Key words: rock mass classification, variable weight, interval fuzzy, membership function, closeness degree