Lateral stress profiles on integral bridge abutments

Abstract

Integral bridges have become established as a viable structural form in many countries for reducing maintenance liability and increasing the robustness of structures. The advent of new design guidance associated with the Eurocodes provides an opportunity to review the design of these structures. Research indicates that peak stresses due to bridge expansion continually increase with cycles and in theory may reach a fully passive state. However, this may not happen in practice during a bridge's life. A numerical model has been developed and calibrated against test data, enabling predictions of the development of lateral stresses acting on a full-height frame integral abutment during its life, both in terms of magnitude and distribution down the wall. Design guidance is shown to be appropriate for bridges up to 60 m long, but to be unconservative for longer bridges. The effect of applying daily cycles of movement rather than just annual cycles has also been investigated.