2nd Croatian Conference on Earthquake Engineering 2CroCEE

Expansion joints on bridges are devices that enable relative displacements of the superstructure spans from the effects of temperature, traffic load and long-term effects. They are placed at the ends of the bridge, where they bridge the space between the superstructure and the abutment, while on very long bridges they are installed at all places where the superstructure breaks between individual sections of the bridge, in order to enable safe and unhindered traffic. They are the “weak points” of the bridge, as their “leakage” can seriously threaten the function of the bridge. In the seismic prone areas, encompassing seismic action in their design and selection is inevitable.

This paper will overview the types of expansion joints, design approach in their selection for new bridges and problems that may arise during their replacement in the rehabilitation process of existing bridges. Movements due to traffic load, seismic movements, movements due to long term effects of the deck (creep and shrinkage) and thermal movements will be considered. Based on practical examples, design for either no damage due to seismic action or partially damaged expansion joints for seismic action, depending on traffic route importance will be contemplated.