Experimental investigation of stress-strain conditions in punching zone of flat slabs

Abstract

The technique and results of experimental study on the test specimens of the stress-strain condition of flat reinforced concrete slabs of a girderless framework at punching by columns of square and rectangular section are presented. The punching shear strength of slabs at rectangular columns can be lower than at square columns with a similar length of the control perimeter. The research of influence of a form of a column cross-section on the stress-strain condition of a reinforced concrete slab in a punching zone is conducted. The comparative analysis of distribution of concrete and reinforcement deformations of reinforced concrete slabs on column perimeter depending on a ratio of the sides of cross section is made. The results of the research of сracking in a zone of punching of reinforced concrete slabs are presented here. Results of the conducted research allow expanding the base of experimental data of the considered subject and promoting improvement of modern positions in the theory of power resistance of reinforced concrete. New experimental data received in the research corresponded with the earlier offered hypothesis that in a slab there is a zone of the constrained deformation located along the perimeter around the rectangular column.