Shear characteristics across simulated discontinuities in the local globigerina limestone

Abstract

Excavations in rock can be quite cumbersome due to the discontinuous nature the said material exhibits. The excavation process may result in potentially unstable rock masses whose factor of safety needs to be established in order to declare the excavation safe or else adopt mitigation measures. Amongst other things this necessitates the evaluation of shear characteristics existing across the discontinuity interfaces. This dissertation aims to study some factors that affect the shear stresses developed at discontinuity surfaces. This is followed by the determination of typical angles of friction corresponding to a number of representative rock discontinuities present in local globigerina limestone. These rock interfaces were simulated by cutting and shaping stones to predetermined forms. Their resultant angles of friction were subsequently found by using the direct shear test method. The said angles of friction may be used as guidelines to assess the stability of potential sliding blocks in geotechnical problems in the local scenario.