A Modeling Approach of Heat Transfer of Bridges Considering Vehicle-Induced Thermal Effects

Abstract

AbstractThe design and application of bridge deicing systems require an understanding of heat-transfer mechanisms of the bridge. One of these systems is geothermal foundations that support structural loads and utilize heat exchange with the surrounding soil. To design such a bridge deicing system and ensure ice-free surfaces during winter, accurate prediction of the temperature of bridge decks is vital. Heat-transfer mechanisms of the bridge deck include many factors such as convection between air and deck, solar radiation, and longwave radiation. Despite considerable research in this area, traffic vehicle effects on the heat balance of the bridge have not been fully investigated. In this paper, a two-dimensional finite-element analysis that focuses on natural factors is proposed and validated using measured data. After the validation, the model was extended to include the vehicle effects for conditions of both light and heavy traffic, considering tire frictional heat and vehicle-induced convection and radiation. The results show that the vehicular traffic increased the bridge surface temperature by up to 2°C with light traffic and by up to 4°C with heavy traffic, thus providing an advantage for deicing. Traffic effects can cool the bridge surface temperature down by up to 2°C, mainly during the summertime. Therefore, the traffic effects can be optionally considered during the design of bridge deicing systems.