Integral abutment bridge hysteresis model for long prediction

Abstract

A numerical prediction methodology utilising hysteresis models was developed to enable long-term response prediction of integral abutment (IA) bridges. Long-term IA bridge behaviour prediction is important due to the nonlinear response of this bridge type, resulting in cumulatively increasing deformations over repeated annual temperature cycles. In order to limit computational demand for long-term simulations, a numerical model condensation technique was performed. Although the condensed model is intended to be simple, the complexity of inelastic IA bridge behaviour and time-dependent effects is fully captured for accurate prediction. The condensed model predicted response is compared with measured responses from field monitoring of three IA bridges in Pennsylvania, as well as predicted responses from two- and three-dimensional (2D and 3D) finite-element (FE) models. Abutment longitudinal displacement is used as a basis for comparison among models, as pile and girder stresses are directly related to this measure. Predicted long-term responses over a 100-year simulation period based on the condensed model and complex 2D FE model are presented and compared. The results indicate that the condensed model is an accurate and efficient alternative to more complex 2D and 3D FE models for predicting the long-term response of IA bridges.