Design and Numerical Evaluation of GFRP Reinforcement for Concrete Bridge Railing

"The aim of this proposal is to provide design and numerical evaluation of glass fiber reinforced polymer (GFRP) bars for concrete bridge railing. The “steel-free” concrete bridge structure concepts have gained wider acceptance in current practice [ref] due to reduced material cost and validated field performance from the past researches. However, on-site bending is still not possible for GFRP bars, which causes increase in the number of GFRP bars used in construction. Alternatively, headed end GFRP bars may address this problem. Existing researches have conducted both experimental and numerical modeling investigations to achieve an optimum design for GFRP reinforcement in concrete structures, especially railings [ref.]. It was suggested that the headed-end GFRP bars can provide sufficient resistance, however, with an added cost. Therefore, anchorage GFRP bars with modified bending radius has also been suggested to achieve same resistance with lower cost. Considering the on-going effort in seeking the optimized GFRP configurations for concrete bridge railings, the preliminary design and numerical validation is critical in finding the best design prior to the field implementation of GFRP bars for concrete bridge railings in the state of Missouri. This proposal aims to provide the preliminary design and numerical validation of GFRP configurations for concrete bridge railings. Both head-ended and pre-bent GFRP bar designs will be proposed for existing concrete bridge railing structures adopted by Missouri Department of Transportation (MoDOT) and evaluated through static and dynamic numerical modeling. The static analysis will be conducted using the ABAQUS® finite element code using damage-based models such as concrete damaging model and phase-field fracturing model. The dynamic analysis will be conducted using LS-Dyna® finite element code, which models the vehicle impacting experiment according to the Manual for Assessing Safety Hardware (MASH) test levels."

This research will provide practical design approaches for GFRP concrete bridge railings and numerical models to evaluate the design.

If successful, the proposed project will deliver an effective design approach to DOT for designing GFRP reinforced concrete bridge railings.

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