11 - Testing techniques

Abstract

The term 'rock properties' refers to those intact rock or rock mass properties that are needed for engineering design purposes. In situ stress is a site property rather than a rock property, but testing techniques are required to determine the in situ stress. The 'permeability' could be included as a separate item under each of the 'intact rock', 'fractures' and 'rock mass', but it is considered the property in a separate category because the subject involves the connectivity of the rock mass fractures. The rock properties can be measured directly or indirectly. This chapter emphasizes that it is not possible to specify the components of a site investigation and the associated testing programme that are universally appropriate for all rock engineering projects. This is because different projects have different objectives. Thus, it is necessary to understand the complexities of the rock mass geometry and mechanical properties in order to make sensible decisions on the optimal site investigation given a specific engineering objective.