ABSTRACT
The world was changing, as if with one piece missing the whole thing had come loose and was running wild.
Ross Macdonald The Underground Man (1971)
3.1 INTRODUCTION
There can be no ‘soil mechanics’ without soil and no ‘rock mechanics’ without rock. Soil and rock are geological materials and to practice rock mechanics in geotechnical engineering, petroleum engineering, mining or nuclear waste studies, it is important to remember that we are dealing with natural geological materials and masses. These rocks owe their characteristics to a long history, which includes the mechanics and chemistry of formation together with subsequent stress history, cementation and weathering. Rocks are neither isotropic nor elastic, even though, in engineering practice, they are generally treated as such for analysis. Rocks contain flaws ranging from microscopic cracks within minerals through to joints at the scale of metres and faults that extend for kilometres.
