88 lntod rock: deformobilify, strength ond failure
The empirical Hoek-Brown criterion has become the most widely
used failure criterion for practical use. The criterion relates to the rock
mass, i.e. the intact rock plus the fractures, and we will discuss it
further in Chapter 8. Three journal publications that review the use of
the criterion for various projects and comment on the reliability of the
estimates are as follows:
Hoek E. and Brown E. T. (1997) Practical estimates of rock mass strength.
Int. J. RockMech. Min. Sci., 34,s’ 1165-1186.
Hoek E. (1998) Reliability of Hoek-Brown estimates of rock mass prop-
erties and their impact on design. Inf. J. Rock Mech. Min. Sci., 35, 1,
63-68.
Hoek E. (1999) Putting Numbers to Geology - An Engineer’s View-
point. Q. J. Eng. Geol., 32,l-19.