Experimental model of plan curved footbridge supported by arch

Abstract

The new type of plan curved structure with the upper deck has been developed within the research of arch structures. The paper describes the process of the research and the design of the physical model in scale 1:10 built for testing of the structure type. The design of the structure has been based on observation of static and dynamic behaviour of arch structures of various radii of plan curvature. Internal forces, deformations and natural modes were monitored for different methods of the design. At first, a simplified method of designing plan curved structures with arch situated in the bridge axis has been investigated and the behaviour of structures designed in accordance with this method has been studied. It has been discovered that simplified method can be used for design of structures with plan curvature radius of 250 m or higher. After investigation of other design methods, the method based on inversion of suspension cable has been chosen for further development. The method has been improved with processes that allow the application for plan curved structures. The result is a plan curved structure supported by a spatial arch. The geometry of the arch corresponds with ideal thrust line of the arch for given permanent loads. The composite structure with steel arch of span of 60,0 m with radius of plan curvature of 37,5 m has been designed and analysed thoroughly in MIDAS Civil software. The behaviour of the calculation model has been compared with behaviour of physical model in scale 1:10 that has been built in laboratory of the Faculty of Civil Engineering of BUT. Results have demonstrated that calculations and measurements correspond.