Micromechanical Model for Predicting Coefficient of Thermal Expansion of Concrete

Abstract

Thermal cracking of Portland cement concrete (PCC) decreases rideability and accelerates deterioration of concrete pavements. Coefficient of thermal expansion (CTE) is one of the most important parameters to evaluate the thermal sensitivity of PCC. The AASHTO mechanistic-empirical pavement design guide (MEPDG) requires CTE as a basic input for concrete pavement design, which has increased interest in studies related to concrete CTE in the United States. Several test methods have been developed and used to determine concrete CTE. Nevertheless, concrete CTE testing is time-consuming. Most of the currently available concrete CTE prediction models are empirical and do not reflect the microstructure of PCC. This paper developed a micromechanical model based on thermal mechanical analysis to predict concrete CTE. Concrete CTE data found in the literature validated the applicability of the developed model. Factors affecting concrete CTE were examined using the proposed model. The model has the potential to estimate concrete CTE for concrete pavement design and to help select appropriate raw materials for PCC to achieve low CTE.