Some attempts on Characterization and Evaluation of Properties of Fracture/Shear Zones

Abstract

This study is concerned with main causes of fault/shear formation and the utilization of various experimental techniques for their evaluating mechanical properties. In the first part, the results of several experimental studies on the formation of fault/shear zones are presented. Then, some proposals have been done how to characterize the geometry, fracturing, morphology, and internal structure of fault/shear zones and some examples are given using some rock classifications. Then, some direct shear tests were performed on the actual fault gouges and their actual characteristics have been evaluated. The characterization and evaluation of the properties of fault/shear zones using RMQR rock classification method are explored. In addition, the utilization of conventional and modified Needle Penetration Index (NPI) for assessing the characteristics of fault/shear core is investigated. Finally, the presented procedures and techniques are applied to actual fault/shear zones and they are validated. © 2022 ARMA, American Rock Mechanics Association.