The Assessment of Mechanical Characteristics of Fracture Zones

摘要

Fracture zones are commonly found in the Earth's crust. Therefore, it is almost impossible not to encounter these zones during large rock excavations. These zones are always problematic causing heavy water in-flow, instability, squeezing during excavation. Therefore, the assessment of mechanical characteristics of these zones is quite important. Nevertheless very few studies undertaken so far on this aspect of fracture zones. In this paper, a brief outline of several techniques for assessing the mechanical characteristics of fracture zones is first given. Then, their validity and applicability are checked through the results of laboratory uniaxial compression tests carried out on model fracture zones. Furthermore, the use of elastic wave velocity method for indirect characterization of these zones is studied.