Analysis of the Slant Shear Test

The slant shear test which subjects the interface of two bonded semi-prisms of concrete and repair system to a combined state of compression and shear is claimed to represent the stress state typical of real structures, but the test has some serious shortcomings. The effects of joint angle (angle of concrete/repair plane), adhesion, orientations of semi-prisms during manufacture, mechanical interlocking and friction along the concrete–repair interface are presented. Theoretical analysis of the factors involved in failure and a comparison of the outcome with the experimental results indicated the existence of a critical joint angle. Although the bond strengths of cementitious and polymer modified repair systems measured by this method did not agree with the respective values obtained using the friction-transfer method, but the trend of bond strengths of the resinous systems tested were similar. The coefficient of variation for the slant shear bond strengths was found to be about 23.5%.