Abstract This paper investigated shear-related roughness classification based on Fuzzy comprehensive evaluation, and established a new strength model of natural rock joint. The joint profiles were extracted from 3D data to evaluate roughness, and a series of direct shear tests were carried out on three kinds of natural rock joints. The height statistical parameters Sm, Sq, Ss and Sk, and the textural statistical parameters Si, Sc, and Z2 were measured by Talysurf morphology instrument. Considering the existence of strong positive relations between Sm and Sq, and Z2 and Si, the four morphological parameters of Si, Sq, Sc, and Sk are considered as the main influencing factors related with rock joint shear behaviors. A new fracture roughness coefficient FRC is proposed based on fuzzy comprehensive evaluation (FCE), which considers that the influence of multi morphology parameters on the roughness of rock joint surface, and generally, the FRC is higher than the JRC. Compared with the previously published shear strength models, the proposed FRC-JCS shear strength model, which can more comprehensively reflect the influence of joint surface morphology parameters to shear strength, are in better agreement with the experimental data.

中文翻译：

---

基于模糊综合评价的天然岩石节理剪切粗糙度分类及强度模型

摘要 研究了基于模糊综合评价的剪切相关粗糙度分类方法，建立了天然岩石节理强度新模型。从 3D 数据中提取节理剖面以评估粗糙度，并对三种天然岩石节理进行了一系列直剪试验。高度统计参数Sm、Sq、Ss和Sk，纹理统计参数Si、Sc、Z2采用Talysurf形态学仪器测量。考虑到 Sm 与 Sq、Z2 与 Si 之间存在强正相关关系，Si、Sq、Sc 和 Sk 四个形态参数被认为是与岩石节理剪切行为相关的主要影响因素。基于模糊综合评价（FCE），提出了一种新的断裂粗糙度系数FRC，考虑了多种形态参数对岩石节理面粗糙度的影响，一般FRC高于JRC。与之前发表的抗剪强度模型相比，本文提出的FRC-JCS抗剪强度模型能够更全面地反映接头表面形貌参数对抗剪强度的影响，与实验数据更加吻合。