Specifying the information required for rock mechanics modelling and rock engineering design

Following two previous papers in which we discussed the ways ahead for rock engineering design methodologies, and presented two updated flow charts, this paper discusses how to establish the necessary quality and quantity of information required for rock engineering modelling and design. We demonstrate how different types of information are required by the different modelling and design methods, via their required inputs and constraints (a corollary being that a ‘standard site investigation’ is not appropriate) and that the degree of co-operation between the site investigation personnel and the modelling and design personnel is a crucial component. A five step procedure for establishing the required information is recommended. Two illustrative rock slope case examples (one ‘simple’, one ‘complicated’) demonstrate the different modelling methods used, the type of information that was obtained for the modelling and design, with the results and conclusions. The paper illustrates the importance of understanding and establishing the necessary information requirements and ensuring that this information is in fact obtainable and obtained.