Concrete Beams with Small Opening under Torsion

Abstract

In order to save headroom in modern high-rise buildings it is often necessary to provide holes or openings at different positions in beams. These openings permit a passage for service ducts. If the beam is subjected to torsion, its torsional strength must be checked or the region near the opening should be reinforced adequately to eliminate the weakness. It has been observed (5,8,9) that by providing suitable reinforcement, it is possible to have large openings in reinforced and prestressed concrete beams subjected to bending and shear.