Optimization For Small Box Girder Design Based On ANSYS

In small and medium-span simply supported-continuous beam bridges, the forms of the main beam’s section are T-shaped, hollow slab, I-shaped, box, combination box, etc. Box-section is more widely used than other forms of cross-section based on their characteristics. The box beam is closed thin-walled cross-section under the structure force, good sectional flexural and torsional stiffness, which can effectively resist the car load, wind load and weight. Its bending and torque are more uniform compared to each piece T-shaped beams under transverse partial load, which has a good integrity in the force. The height and width of precast beam section have little difference so that the beam has good stability in the construction and using of the process. From the view of aesthetic point, box girder cross-section have simple shape and straightforward lines applicable to flyovers, overpasses, etc. It is because of box-section girder bridge so widely used that optimizing the size of the box girder to achieve better economic efficiency has a very important practical significance.This article relies on actual projects through embedding concrete sensors in the beam prefabricated and conducting the load test for the box girder bridge when the bridge is built, then measures strain and deflection when the bridge under loads. Creating a box girder model calculation model with the ANSYS finite element software simulates the bridge under the actual load. The reasonableness of the finite element model is verified through comparative analysis of the measured data by the finite element analysis.The bending capacity optimization of small box girder cross-section is designed under the load using sub-problem approximation method to meet regulatory requirements and working conditions,which is based ANSYS optimization module.The conclusion is optimal size of small box girder cross-section, and its economic analysis of material consumption.