A Consideration on the Shear Strength of Rock Masses

Abstract

In this work, an empirical equation that is derived from Ladanyi's shear strength theory of jointed rock masses is proposed.
This equation is expressed as follows.
While Ladanyi's equation is expressed as follow.
In this empirical equation, the factor “β” that depends on the continuity of rock joints is considered.
The value of this factor “β” can be found, β=1 for highly jointed rock masses, β=O for intact rock and O<β<1 (in many casies β=0.5-0.85) for the intermediate states of the rock masses.
Theoretical shear strength curves are suggested by the combination of general φ_b (basic friction angle), i (dilation angle), σ_c (uniaxial compressive strength) and “β”.
The relation between the theoretical shear strength carves and measured strength values which are obtained from in situ block shear test is examine in many casies.