Bridges

Wheel loads are often a critical design case for buried arch structures, especially for structures with shallow cover, or loaded by large mining vehicles. Analysis for wheel load effects on these structures is normally carried out on the basis of a 2D analysis with simplified load distribution in accordance with the Australian Standard Bridge Design Code, but the provisions of the code for distribution of wheel loads through fill are based on classical elastic solutions for stress distribution in uniform materials. They do not take account of non-linear soil behaviour, 3D interaction effects between the soil and the structure, or of the behaviour of structures with differing longitudinal connectivity.This paper provides a brief review of previous research and reports the results of a series of non-linear 3D finite element analyses on typical concrete buried arch structures, comparing the results with standard 2D analysis methods. The analyses include varying vehicle loads, fill heights, and arch dimensions, and three different longitudinal arrangements, from independent pre-cast segments to fully continuous structures.The paper provides recommendations for the analysis and design for vehicle loads on buried arch structures, both for critical design actions in the structure, and for prediction of structural deflections.