Shear Behavior Model for FRP-Confined and Unconfined Rubberized Concrete

This paper presents the experimental and numerical results of an ongoing investigation aimed at developing high-strength, high-deformability fiber-reinforced polymer (FRP) confined rubberized concrete (CRuC) suitable for structural applications. The rubberized concrete (RuC) utilizes recycled rubber particles as a replacement for both fine and coarse aggregates. Rubber aggregates reduce the compressive strength and stiffness of RuC, thus limiting its application for structural purposes. Confining RuC with FRP jackets recovers strength and enables the development of high deformability, ductility, and energy dissipation capacity. Recent research mainly focuses on the axial performance of RuC and CRuC, but little work exists on the shear behavior of this flexible concretes. This paper adopts a nonlinear numerical approach for the practical implementation of the smeared, fixed-angle crack approach in finite element analysis to predict the shear response of RuC and CRuC. Constitutive models are proposed on the basis of fundamental test results. The model is validated through a simulation of a series of shear tests on RuC and CRuC with different shear span-to-depth ratios (a/d). The model predictions are then compared against the experimental results, and good agreement is found.