Finite Element Simulation And Application Of Highway Widening Bridges

The existing structure of the bridge reconstruction and expansion project does not correspond to the load grade of the old bridge.The materials and construction techniques used in the old bridge are backward,and the stress performance test of the bridge structure is difficult and costly.However,with the development of computer simulation technology,it provides a convenient and fast method for testing the performance of bridges.Based on the reconstruction and expansion project of the Jing-Tibet Expressway,this paper carried out finite element simulation on the upper and lower structure of the widened bridge,simulated and analyzed some of the structures in the bridge widening scheme,and provided the choice for the highway bridge widening scheme.Theoretical basis.This paper first compares the widening schemes commonly used in the reconstruction and expansion projects and their advantages and disadvantages.Combined with the actual situation of the project,the principle of widening the upper structure and the unconnected lower structure is selected.Using the finite element simulation software MIDAS/Civil to build the finite element simulation model of the upper bridge structure,the lower structure and the widened rear upper structure of some hollow slab girder bridges,the finite element simulation model was established according to different spans and pier heights.Calculation of bending load capacity and calculation of bending,compression and crack width of the substructure.The calculation results show that the bearing capacity of 8m and 10 m span hollow slabs in the superstructure does not meet the requirements of widening bearing capacity and the difference is large.The 13 m hollow slab also does not meet the bearing capacity after widening but the difference is small;1620m hollow slab Meet the requirements of the load capacity after widening.The lower structural experience calculations all meet the requirements of the bearing capacity and crack width after widening.Based on the analysis and calculation results,this paper establishes and improves the 8m,10 m,13m span hollow slab girder bridge to adopt the demolition and reconstruction plan and the 16 m,20m span hollow slab girder bridge to adopt the scheme of repairing and strengthening the original structure and then widening the utilization.The research results have certain guidance and reference significance for the subsequent decision-making and widening program design of similar projects.