Integral abutment bridges (IAB) have become increasingly popular in the past few decades due to their design simplicity. UK design rules limit the length of IABs to 60 m, due to the issues associated with thermal strains, settlement, and pressure build-up behind the abutment. A cyclic loading test, representing seasonal thermal fluctuations, was conducted on a 1/12 scaled-down retaining wall of a conventional full-height IAB. The test was then repeated with the inclusion of displacement compensation units (DCU) in the form of conical disc springs (CDS) and hollow rubber cylinders (HRC), which operate in a pre-deformed shape. The results show some remarkable improvements in the IAB performance with DCUs. The soil backfill pressure was reduced to 30% and 47% with CDSs and HRCs, respectively. Furthermore, no settlement was observed, as compared to the conventional IAB test which recorded a 20 mm settlement after 100 cycles. Non-linearity in the force-deflection behaviour of DCUs enables expansion and contraction of the deck to be accommodated with minimal fluctuation of backfill pressure. Finally, a finite element (FE) model of an HRC applied with two temperatures has been analysed and compared with the IAB wall test, which suggests that both analyses showed some correlation.

Integral abutment bridges (IABs) are a family of jointless bridges that have gained popularity owing to their simplified designs and sustainable construction practices. IABs are small- and medium-span bridges that do not have expansion joints or bearings, thereby reducing the cost of maintenance. The span of IABs is primarily dependent on the magnitude of the thermal stresses considered during the design process. However, the adoption of IABs has been limited globally because of the inherent complexity of the design caused by the large number of indeterminacies originating from rigid connections and soil-spile interactions. This has led to variations in the design of IABs among transportation agencies worldwide. This literature review aims to highlight the variations in major IAB projects constructed worldwide. Additionally, the bibliographic analysis performed for IABs identified key topics studied by researchers, which are discussed in detail in the current state-ofthe-art. The objective of this literature survey is to provide practical bridge designers and researchers with an understanding of previous and ongoing developments in IABs.