Abstract
The appropriate modeling of mechanical behavior of a discontinuity and the quantitative determination of its characteristics have an important role on evaluating the stability and deformational behavior of structures in the discontinuous rock masses. This paper is to present the laboratory test techniques and a rational procedure for the determination of deformational characters and strength of natural rock joints. The problems concerning with the assessment of these characteristics in the previous analysis are also pointed out based on the investigation of the shear tests conducted on several types of real natural joints. The distinct element analyses, in which both liner shear stiffness and non-linear one are introduced for the same ground conditions, are also carried out to clarify the effect of non-linearity of shear stiffness on the deformational behavior of rock structures.
