Behaviour of flexural plastic hinges under high seismic shear with consideration of concrete strength

Abstract

A successful seismic design for a reinforced concrete element is one that can postpone the shear failure until the required ductility and deformation capacity are obtained. After flexural yielding, shear deformations are the main causes for strength and stiffness degradation. An experimental program was carried out to explore the shear behaviour of flexural plastic hinges of elements constructed with different concrete strengths (30–175 MPa) tested under load reversals. The specimen represented a beam–column assembly and was designed to have the inelastic deformation at the beam end only. The research investigated the effect of shear deformations on the hysteretic behaviour and stiffness deterioration, cyclic shear demands, shear resisting mechanisms, and the effect of concrete strength on the hinge shear strength. It was found that the effect of concrete strength on beam shear strength under cyclic loading differs from that under unidirectional loading.