Thermal Effect on Rheological Properties of Epoxy Asphalt Mixture and Stress Prediction for Bridge Deck Paving

摘要

Epoxy asphalt mixture has been widely used as an excellent paving material on long-span steel bridges; however, low-temperature cracking is a significant concern for paving on an orthotropic steel deck. Analysis of low-temperature thermal stress can be a challenge owing to the varying modulus of epoxy resin asphalt mixture at different temperatures. This paper presents an investigation into the rheological behaviors and models for epoxy resin asphalt mixture under different temperatures. Bending creep tests were conducted in a range of temperatures from 10 degrees C to 60 degrees C, and creep compliance curves were obtained. Based on the test results, five succinct but practical viscoelastic models were used for creep modeling, and parameters corresponding to different temperatures were obtained. Using a numerical approach, the creep compliance results were converted into master curves of relaxation modulus, and then the low-temperature thermal stress was calculated for the pavement layer. The experimental and simulation results indicated that the modified second-order extensive Kelvin model could be used to describe creep performance very well for epoxy resin asphalt mixture in a wide range of temperatures, and epoxy asphalt is highly adaptable to a cold working environment when used as the paving layer of steel bridge decks.