Punching Strength of Reinforced Concrete Slabs.

A method of evaluation of the punching strength of reinforced concrete slabs is presented and the correlation between punching resistance and flexural strength clearly established. The punching resistance depends mainly on the reinforcement strength as in the case of flexural strength. It is shown that the effect of the concrete strength on punching resistance is of the same order of magnitude as it is on the flexural strength and can be expressed by the factor I -- g/2 used in the analysis of the ultimate flexural strength of reinforced concrete members. The theory is substantiated by test data. The effectiveness of bending up a part of the flexural reinforcement is discussed. It is proved by a series of tests that by bending up a part of the flexural reinforcement the punching strength of flat slabs can be secured. The method is directly applicable to the design of the column region of flat slabs and suitable charts are provided. [ABSTRACT FROM AUTHOR]