Thermal Stress Calculation Method for Concrete Pavement Based on Temperature Prediction and Finite Element Method Analysis

Abstract

A method to predict thermal stress of a concrete slab was developed in this study. In this method, temperatures and thermal stresses in a concrete slab are predicted by solving a one-dimensional heat transfer equation with the control volume method and three-dimensional finite element method (3DFEM). Predicted temperatures were compared with those measured in various regions in Japan to validate the method. The thermal strains calculated with 3DFEM were also compared with those measured in test concrete pavement slabs to confirm the method’s validity. The relative frequencies of thermal stress for one year were obtained from the calculated stresses. In thin slabs (20 and 23 cm), tensile thermal stress at the bottom was greater than those estimated with the current thermal stress equation, which considers internal stress due to the nonlinearity of the temperature profile in the slab. In thick slabs (25 and 30 cm), by contrast, the current thermal stress equation gave almost the same thermal stress as the finite element method did, although the peak time for the maximum tensile stress was delayed in the thick slabs. The proposed method can be applied to a variety of concrete pavement structures under various temperature conditions.