Finite Element Modeling of Longitudinal Field-Cast Connections Between Precast Deck Bulb-T Bridge Girders

Abstract

An alternative mix design using polypropylene fiber-reinforced high early strength concrete was proposed by the Idaho Transportation Department for the longitudinal connections between deck bulb-T precast bridge girders in accelerated bridge construction. In this paper, finite element models of the pullout behavior of headed reinforcing bars in the closure pour and bending tests of beams representing a 30 cm strip of the bridge deck were developed. The smeared crack model was used for concrete, while cohesive zone modeling showed good results in representing the interface between the closure pour and precast concrete. Steel–concrete bond-slip behavior was observed to be one of the most significant factors affecting the results. A scheme to simulate this behavior using zero-length nonlinear spring elements was designed. The finite element models were able to produce results similar to the experimental findings.