PURPOSES : Steel deck bridges are the preferred structural type for reducing dead load, and the use of thin-layer asphalt concrete with excellent adhesion to the steel deck and excellent deformation followability is increasing for bridge pavements. However, because these materials are constructed at a high temperature of 240 °C or higher to maintain high fluidity during construction, excessive thermal deformation and stress may be temporarily induced in the steel deck. Therefore, the stability of the structure must be assessed by considering the environmental conditions of the site during pavement construction. Herein, a method is presented for estimating the heat source equation, in which conduction and convection effects are removed using temperature measurement data, for modeling U-rib using plate elements. The validity of the study is assessed by deriving the equivalent heat source equation using the temperature data measured from the underside of the steel deck while constructing a 40-mm-thick goose asphalt concrete pavement layer on a 12-mm-thick steel deck. In addition, the practicality is verified by performing heat transfer and thermal stress analyses. METHODS : By comparing the temperature data measured during the construction of high-fluidity asphalt concrete with the results of repeated heat transfer numerical analysis, heat source data without field conduction and convection conditions are obtained. Subsequently, a heat source equation suitable for the heat source data is derived using the least-squares method. RESULTS : The results of the heat transfer analysis using the equivalent heat source equation calculated using the presented method are almost consistent with the measured temperature data. In addition, the behavioral characteristics of the structure that matches the behavior of the actual structure can be derived through thermal stress analysis, which considers heat conduction and convection to adjacent members. CONCLUSIONS : Even when the steel deck and U-rib member are modeled as plate elements, thermal effect analysis can be performed reasonably while considering field conditions.