Integral bridge abutment-soil interaction analysis using PIV technique

Integral abutment bridges(IABs) are bridges designed without the use of expansion joints. Hence, the superstructure and substructure of IABs translate or rotate in unison to accommodate alternate cycles of expansion and contraction due to temperature changes. IABs are less expensive to construct and easier to maintain, compared to traditional bridges with joints. However, IABs also result in complex soil-structure interactions problem created by thermally induced cyclic movements imposed on the approach embankments to integral bridge abutments. As a consequence, the wall movements create more uncertainty in predicting the lateral earth pressure distributions, and the soil settlement and heaving behind the abutment wall. This paper presents a study of the soil-abutment interaction of an IAB during translational active and passive movements of the abutment. Particle image velocimetry(PIV) technique has been used to observe the soil deformation, and to explain the ratcheting of the lateral earth pressure distribution and the development of settlement trough and surface heave at the back of the abutment