Comparing the strain ratcheting of soil behind integral bridge abutments in field and physical modelling data

Abstract

Integral bridge abutments are designed to withstand an increase in earth pressure caused by repeated thermal movements of the bridge deck. UK design is largely based on physical modelling due to challenges in recording long-term pressures in the field, however, there is a need for agreement between the two. This study compared the findings from field monitoring and physical modelling reported in the literature to explore the development of earth pressures in the backfill of integral bridges. The results show similarities between field and modelling data, with a limited pressure increase expected for many bridges due to the low strains experienced. However, the design temperature range used to estimate thermal movements may cause an overprediction of long-term pressures.