Shearing strength of plain concrete based of push off tests

This paper present the results of an experimental investigation of the shearing strength of plain concrete based on pushoff type of tests. Twenty pushoff specimens with compressive strengths ranging from 19 to 66 MPa were cast and tested to failure. The results indicate that the cracking shearing strength increase with the increase in compressive strength. However, the rate of increase diminishes as the compressive strength increases. An equation relating the cracking shearing strength to the compressive strength of the concrete is proposed. This equation can be used to calculate the cracking shear stresses in elements which are commonly designed using the shear-friction model.