THE SHEAR STRENGTH OF RC COUPLING BEAMSWITH PLASTIC HINGES USING STRUT-AND-TIE MODEL

摘要

In this study, a strut-and-tie model for the coupling beam accompanying plastic hinges is presented.Assuming the required plastic deformation at both ends of the coupling beam, the strut-and-tie model isconstructed. To design earthquake-resistant shear-dominated RC coupling beams, it is important toconsider shear strength deterioration with required ductility. This study proposes the method of estimatingshear strength of the reinforced concrete coupling beams considering the strength degradation of thediagonally compressed concrete due to the strain in plastic hinges. The proposed method determines theplastic strain from required plastic deformations based on the elastic deformation of coupling beams andultimate wall deformations. The estimated horizontal strain of beam is then used in calculating thestrength of the diagonal strut of arch action with compatibility conditions. The deterioration of shearstrength of the coupling beam depends on the decrease of arch action due to plastic deformations.