Two-parameter kinematic approach for the shear behaviour of deep beams made of fiber-reinforced concrete

Abstract

The main aim of this thesis is to study a five-spring model for deep beams with conventional reinforcement proposed by Mihaylov et al. (2015), and to extend this model to deep beams with FRC. The five-spring model uses only two kinematic parameters to describe the deformations in deep beams. The extended model captures the complete load-displacement response of FRC beams by accounting for three effects associated with the steel fibers: 1) tension in the fibers crossing the shear cracks; 2) enhanced ductility of the critical compressed zones in deep beams; and 3) tension stiffening effect on the flexural reinforcement. To account for these three local effects, existing models from the literature are studied, compared, and validated.The main aim of this thesis is to study a five-spring model for deep beams with conventional reinforcement proposed by Mihaylov et al. (2015), and to extend this model to deep beams with FRC. The five-spring model uses only two kinematic parameters to describe the deformations in deep beams. The extended model captures the complete load-displacement response of FRC beams by accounting for three effects associated with the steel fibers: 1) tension in the fibers crossing the shear cracks; 2) enhanced ductility of the critical compressed zones in deep beams; and 3) tension stiffening effect on the flexural reinforcement. To account for these three local effects, existing models from the literature are studied, compared, and validated.