Mechanical properties analysis of super-large diameter steel corrugated pipe arch culverts under different high filling depths

The filling height during the construction phase has a significant impact on the mechanical properties of super-large-diameter steel bellows arch culverts. To ensure the construction safety of super-large-diameter steel bellows arch culverts, this paper established 12 super-large-diameter steel bellows arch culverts, and calculated the deformation and stress of the overall structure under the operation stage of self-weight, vehicle load and earth pressure; then the refined finite element models of the No.1 bellows with a diameter of 8.79 m and the No.6 bellows with a diameter of 11.00 m were established. The deformation characteristics and stress of the two corrugated pipe culverts with different diameters were analyzed under different filling heights at different construction stages. The results show that, as the fill height increases to 7 m, the vertical displacement and stress of the No.1 bellows increase continuously, while the displacement and stress of the No.6 bellows initially decrease and then increase, and the horizontal displacements at the top and bottom of the pipe are very small but their vertical displacements are very large. Under the combined action of self-weight and soil stress, the maximum vertical displacement of the soil and bellows is 67.16 mm and 39.28 mm, respectively, and the maximum tension and pressure of bellows are 13.95 MPa and 2.95 MPa; Under the vehicle load, the maximum vertical displacement of the bellows is 10.37 mm, and the maximum tension and pressure of the bellows are 26.65 MPa and 0.47 MPa, respectively. Thus, all the above calculation results meet the structural deformation and stress requirements. As for the larger structural vertical deformations under different fill heights, it is recommended to increase the compaction of the underlying soil. The research results are of great significance for the promotion and application of ultra-large diameter steel corrugated pipe culverts.