The effect of infill on shear behaviour of idealised joints under constant normal stiffness conditions (CNS)

Abstract

The shear behaviour rock joints infilled with graphite, bentonite and clayey sand under eNS conditions were studied through a comprehensive laboratory testing programme to assess its influence on rock mass stability. A range of infill thicknesses such as 1.5, 3, 6 and 9mm, initial normal stresses (O'no) of 0.56, 1.1 and 2.43 MPa and two idealized joint types with 9.5° (Type 1) and 18.5° (Type 2) asperity angles were used in testing (Indraratna, Welideniya and Brown. 2005). This paper describes analysis of test results leading to better understand the effect of mobilised and apparent friction angles on shear strength envelope.