Based on existing test data and the results of recent experiments conducted at the Delft University of Technology, the authors propose new shear friction equations for determining the shear capacity at the cracked interface of reinforced concrete members. The new formulas take into consideration the influence of concrete strength as a basic parameter. To facilitate the calculations, a design chart (which takes into account the effect of high strength concrete) is included. Design examples compare the results of the proposed method with the PCI Design Handbook. Lastly, the influence of previous load cycles on the shear capacity of cracked concrete members is studied.
