Deformability of joints and its relation to rock foundation settlements

Abstract

This study explores several aspects of the 'discontinuous' approach to prediction of settlements of foundations on jointed rock. The first part presents the results of experiments with numerical and analytical solutions. It is shown that solutions of continuum elasticity cannot be used without introducing errors due to method alone, which could be serious for sensitive structures.The second part of the study describes measurements of joint stiffness on samples of natural joints in limestone and sandstone. Normal and shear stiffness coefficients were measured. It was found that the unit shear stiffness coefficient varies greatly with displacement, and an empirical relationship was derived that might be useful in analysing other rocks.