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This study describes an application of a modified strut-and-tie model (STM) for determining the strength of reinforcement-free bridge decks on concrete wide-flanged girders. The method could also be applied to other short-span restrained concrete slabs. The concept presented for the reinforcement-free bridge deck includes a combination of removing steel reinforcement, using compressive membrane action in the deck by tying girders together, and introducing a polypropylene fiber to control shrinkage cracks. An analysis method for these reinforcement-free decks using a modified STM that considers geometrical nonlinearity is proposed. The model provides a two-dimensional (2-D) axisymmetric representation of the behavior of the reinforcement-free deck, and it is capable of capturing punching and flexural failure. Comparisons to nonlinear finite element method (FEM) analysis results were made to verify the proposed analysis method. A design load appropriate for reinforcement-free bridge decks is proposed. [ABSTRACT FROM AUTHOR]

A feasibility study in which the use of a commercially produced pultruded fiber reinforced polymer (FRP) plank for both permanent formwork and secondary or primary tensile reinforcement of a concrete structural member is described in this paper. To achieve satisfactory bond at the interface between the smooth surface of the FRP plank and the concrete, two kinds of aggregate, gravel and sand, were epoxy bonded to the planks. Concrete beams using the aggregate-coated FRP planks were fabricated and tested. Satisfactory bond between the FRP plank and the concrete was developed which was evidenced by numerous well-distributed flexural cracks, and ultimate capacities of the aggregate coated FRP plank specimens greater than the steel rebar reinforced control specimen. ACI 440 equations were found to provide good predictions of the flexural strengths but poor predictions of the shear strengths of the FRP plank reinforced beams. ACI 318 equations, however, provided good shear strength predictions. [ABSTRACT FROM AUTHOR]