Finite Element Analysis Of Temperature Field And Effect On Concrete Box Girder

Girder bridge is an ancient structure system of bridge structures, Among theexisting large-span prestressed concrete girder bridge, the cross-section usually uses abox-shaped cross section. When the box girder’s deformation due to the heating andcooling was restrained, it will produce thermal stresses. This paper was based on theproject of the XingFuYuan Reservoir Double Track Bridge. The objectives of thisresearch are to investigate the temperature field and thermal effect of the bridge due tothe factors of heating and cooling.The primary work of this paper are as follows:①Measured the temperature distributions on the cross-section of the backgroundbridge. Made a brief introduction of the test plans. Carried out a detailed analysis of thetemperature field of the girder due to the heating and cooling. Provided a great majorityof valuable measured data for the numerical analysis.②Introduced the finite element theory of calculating the temperature field andthermal stresses. Introduced the basic theory of heat conduction, including Fourier heatconduction differential equation and the definite condition of solving the equations.Described the Finite Element Method of calculating the transient temperature fieldbased on the variational principle. Through the establishment of the basic equations ofspace thermal stresses problem, this paper introduced the Finite Element Method forsolving the elastic thermal stress problems which lays a theoretical foundation for thetemperature field and thermal effect analysis.③The FEM software ANSYS was used for numerical simulation of temperaturefield and thermal effect. According to the first kind of boundary condition, this papercreated a2D FE model by using the experimental data and simulated the temperaturefield due to the heating and cooling. Compiled a parameterized command flow based onthe second and the third kind boundary condition and compared the calculated andmeasured data which verified the accuracy and reliability of the numerical analysis.Fitted out the temperature curve along the height and width of the cross section by datasorting and linear regression. Based on the temperature curve fitted previously, an3DFE model was created to analysis the transverse and longitudinal thermal stresses.④Analysised the thermal effects of the girder due to the cooling. By introducing acold wave intensity, the working condition of the four different cold wave intensity were constructed. Based on the third kind of boundary condition, an parameterized FEmodel was created to analysis the thermal effects of different working condition bychanging the intensity of cold wave parameters.