In-plane stiffness of reinforced concrete slabs under compressive membrane action

Abstract

The ultimate load capacity of reinforced concrete slabs laterally restrained at their perimeter supports is very sensitive to the in-plane stiffness of the surrounds and of the slab itself An examination of previous experimental work suggests that the assumption of an elastic full depth of element, which is frequently used for the slab self-stiffness in the theoretical load prediction of compressive membrane slabs, is an overestimate. In a programme of experimental work on elements under combined bending moment and axial force reflecting the stress states at fixed stages during yield of a one-way spanning slab, the axial stiffness was shown to be dependent upon the stress state and considerably less than the full depth stiffness.