Punching shear resistance of high-strength concrete slabs

The use of high-strength concrete in reinforced concrete slabs is becoming popular in Australia and other countries. Current design provisions of AS3600 and other major codes throughout the world are based on empirical relationships developed from tests on low-strength concrete. In this paper, the experimental results from 4 research studies are used to review the existing recommendations in design codes for punching shear failure of slabs. Design codes referred in this study are AS3600 and CEB-FIP MC 90. In AS3600 the punching shear strength is expressed as proportional to fc1/2. However in CEB-FIP MC 90 punching shear strength is assumed to be proportional to fc1/3. It is shown that the present provisions in AS3600 are applicable up to 100 MPa.