Analysis and behaviour of CFRP-strips at deviation saddle for CFRP prestressed bridges

This research work presents the application of CFRP-Strips as prestressing elements for bridges, e.g. extradosed bridges and externally prestressed box girder concrete bridges. The application of CFRP-Strips as external pre-tensioned elements is not only governed by the general structural and dynamic behaviour of the hybrid system but also by having the right concept for the construction joints, i.e. the anchorage of the CFRP-Strips at the deviation saddle and at the deck structure. The load bearing capacity and the deformational behaviour of deviated CFRP-Strips is influenced mainly by contact surface, the deviation angle and the diameter of the deviation saddle. This paper introduces the results of an Experimental program of deviated CFRP-Strips at deviation saddle. The effect of the different parameters on the load bearing capacity, strain responses up to failure and the mode of failure of the CFRP-Strip at the deviation saddle will be investigated. Additionally, analytical study for the application of externally prestressed concrete bridges, i.e. Extradosed bridges is presented to highlight the efficiency of this application.