ABSTRACT
When characterising a rock mass for rock engineering design, it would be convenient if the rock were a CHILE material (Continuous, Homogeneous, Isotropic and Linearly Elastic). This would considerably simplify the site investigation and modelling procedures. However, rock masses are not CHILE materials: they are DIANE materials, i.e., Discontinuous, Inhomogeneous, Anisotropic and Not Elastic-which complicates the site investigation, modelling and design studies, and is a raison d’être for this book. Moreover, a rock mass is not like a specimen in a testing machine waiting to be loaded. Rock masses are pre-loaded with an in situ state of stress caused mainly by the movement of tectonic plates. Therefore, in our overall context of ‘risk’, it is critical that the two factors, rock fractures and in situ rock stress, are understood and taken into account during the modelling, design and construction for rock engineering structures.
