A New Combined Servo-Controlled Loading Frame/Direct-Shear Apparatus for the Study of Concrete or Rock Joint Behavior Under Different Boundary and Loading Conditions
A new combined servo-controlled loading frame/direct-shear apparatus has recently been developed at the Civil Engineering Department of Université de Sherbrooke. This direct-shear device is capable of shear testing of rock joints under constant normal stiffness or constant normal load boundary conditions. Due to its combination with a servo-controlled loading frame, it allows load as well as strain and stroke control, including static and cyclic paths. This paper describes this direct-shear apparatus and illustrates results of static and cyclic shear tests undertaken on circular-section rock specimens with irregular interface geometry and on regular-shaped interface specimens made from cement-based mortar.