Effects of CFRP Strengthening on Dynamic and Fatigue Responses of Composite Bridge

Abstract EN

This paper investigates the effect of CFRP strengthening on dynamic and fatigue responses of composite bridge using finite element program ABAQUS.

Dynamic and fatigue responses of composite bridge due to truck load based on AASHTO standard are investigated.

Two types of CFRP strengthening techniques, CFRP sheets and CFRP deck, are applied to both the damaged and undamaged bridges.

For the case of damaged bridge, two through-thickness crack sizes, 3 mm and 6 mm in depth, are assumed at midspan of the steel girders.

Furthermore, effects of the number of steel girders on the dynamic and fatigue responses are also considered.

The results show that the maximum responses of composite bridges occur for dual lane cases.

By using CFRP as a strengthening material, the maximum stress and deflection of the steel girders reduce and consequently increase the fatigue life of the girders.

After introducing initial crack into the steel girders of the composite bridges, the fatigue life of the bridges is dramatically reduced.

However, the overall performance of the damaged composite bridge can be improved by using CFRP, albeit with less effectiveness.

Therefore, if cracks are found, steel welding must be performed before strengthening the composite bridge by CFRP.