Thermal Behavior of Composite Girder Bridges

For composite girder bridges, thermal effects could not be ignored which is significant when compared to dead or live load effects. Temperature distributions involved in concrete bridges and composite girder bridges are at best different due to dissimilar material properties and cross sections. This paper presents the characteristics of the temperature field for composite girder bridges. The relationship between the ambient temperature field and the structural temperature field is analyzed. The principle of Fourier heat theory is adopted to establish a numerical model for the composite girder. Simulation results verify the effectiveness of the proposed method. Based on this, the structural temperature filed can be simplified as the thermal gradient for composite girder bridges, which has practical value in the design for reasonable controlling the thermal displacement.