Structural performance evaluation of innovative composite pedestrian arch bridge

Abstract

This paper proposes an innovative pedestrian arch bridge, with a new bi-layer composite deck supported by a steel frame. Bottom and top layers of the bridge deck are composed of glass fibre reinforced polymer (GFRP) plate and laminated glass plate respectively. Structural evaluation of this aesthetically pleasing and lightweight pedestrian bridges is important to avoid excessive vibration. With this in mind, free vibration tests were first carried out on the proposed composite deck and results were used to validate a three-dimensional finite element (FE) model of the composite deck developed in ABAQUS software. Static and free vibration responses of the proposed pedestrian arch bridge with steel frame and composite deck are evaluated by FE analyses. While the static performance of the bridge was found to be satisfactory, the fundamental natural frequency was found to be within human walking frequency which could cause excessive vibration. Hence, further analysis was carried out by changing the cross-sectional areas of the bridge parts to obtain the desired performance of the bridge. Results were compared with recommended values in Bridge Design Code and they ensured that the proposed pedestrian arch bridge will be a safe, aesthetically pleasing and serviceable structure for the pedestrians.