Express method of testing jointed weak rock masses

One of the principal criteria, in designing a hydraulic structure or evaluating stability of natural slopes, man-made slopes, underground workings etc, is the rock mass strength. The evaluation of this strength for the rock mass having displaced joint systems or other discontinua which make it blocky in structure is a difficult task necessitating large scale in-situ tests. The rock rrass strength values depend on a number of factors such as the strength of rock blocks ( determined by testing small specimens), strength of their contact interlock, scale factor, separate block difference in strength and de — formability, shape of blocks and orientation of joints in respect of the principal stress vector.