Punching shear strength of simply supported ferrocement slabs

The results of punching shear tests on 31 square ferrocement slabs are repo rted in this paper, The slabs were simply supported on all four sides and t ested under a central concentrated load. The parameters investigated includ e the width of square loaded area w, mortar strength f(c)', volume fraction of reinforcement V-J, depth of slab h, and the effective span l. All slabs failed first in punching without total separation, and then exhibited a se cond peak in the load-deflection history. Both cracking load and punching s hear load increased with an increase in w, V-J, f(c)', or h, but decreased as l is increased. The critical perimeter for punching shear failure was fo und to be located at a distance of 1.5h from the edge of the loading plate. Based on the present test data as well as those available in the literatur e, an equation has been proposed for predicting the punching shear strength of ferrocement.