The cast iron deck modules is a lightweight deck slab with excellent fatigue resistance. Friction joint are used to join the cast iron deck modules and the main girder. In this study, the effect of the structural type of the support member between the deck and the girder on the slip behavior and composite effect are investigated by FE analysis. As a result, the reduction rate of the slip coefficient due to the difference in shape of the support member between the cast iron deck module and the main girder was evaluated from the coefficient calculated by multiplying the friction coefficient by the correction coefficient of slip coefficient.
