Beams with Small Rectangular Opening Under Torsion, Bending, and Shear

Abstract

A set of generalized strength equations based on the skewbending model has been developed to predict the torsional strength and failure mode of reinforced concrete beams with or without a small transverse opening. A torsion‐bending‐shear interaction surface is generated using the proposed strength equations. Twenty‐four rectangular reinforced‐concrete beams containing a transverse opening of constant dimensions were grouped into four different series and were tested under various combinations of torsion, bending, and shear. The parameters were the ratio between top and bottom longitudinal reinforcement, the torsion‐moment ratio, and the moment‐shear ratio. Close agreement is observed between the theoretical predictions and the test results of the writers and of other investigators.