Showing papers by "Evert Hoek published in 2007"

A brief history of the development of the Hoek-Brown failure criterion

Abstract: The Hoek-Brown failure criterion was developed in the late 1970s to provide input for the design of underground excavations. Bieniawski’s RMR was originally used to link the criterion to engineering geology input from the field but a more specific classification system called the Geological Strength Index (GSI) was introduced in 1995. Both the Hoek Brown criterion and the GSI classification have evolved and continue to evolve to meet new applications and to deal with unusual conditions encountered by users.

Geological Strength Index (GSI). A characterization tool for assessing engineering properties for rock masses

Abstract: The Geological Strength Index (GSI) is a system of rock mass characterization that has been developed in engineering rock mechanics to meet the need for reliable input data related to rock mass properties required as input for numerical analysis or closed-form solutions for designing tunnels, slopes, or foundations in rocks. The geological character of the rock material, together with the visual assessment of the mass it forms, is used as a direct input for the selection of parameters for predicting rock mass strength and deformability. This approach enables a rock mass to be considered as a mechanical continuum without losing the influence that geology has on its mechanical properties. It also provides a field method for characterizing difficult-to-describe rock masses. Recommendations on the use of GSI are given and, in addition, cases where the GSI is not applicable are discussed.