Design of foundations on discontinuous rock

Abstract

The notion that is the ultimate good foundation is misleading. Many masses are so strong and stiff that bearing capacity is virtually inexhaustible however, rock includes a wider range of properties and attributes than any other group of engineering materials. Sometimes behaviour is only moderately satisfactory and occasionally it is unsatisfactory or perilous. Problems can arise due to pre-existing discontinuities, pores, cavities, old mine openings and compressible seams, swelling or rebound, aggressive waters, and soluble or otherwise non-durable types. It is safe to say that any major foundation installation on demands a comprehensive engineering geology investigation. To proceed otherwise is to play without a full deck. In the case of discontinuous rock, a set of procedures is indicated whereby the settlement and bearing capacity of shallow and deep foundations may be estimated. Many parameters of rocks and discontinuities are needed explicitly or implicitly to apply these procedures yet few or discontinuity properties can be determined with precision.