A study on structural behaviour of corrugated soil-steel bridge structure (long span) in Southern highway for different depth of soil cover

Abstract

Corrugated Soil-Steel Bridges have been used as underpass and drainage structures in the Southern Highway Project. This design and construction process is novel to the Sri Lankan context. The Ring Compression theory, which is based on two dimensional plain strain idealizations, has been used in the design of the structures. However due to the presence of the ring walls, the effect of uneven loading in the longitudinal direction due to load combinations of HA and HB loads, these assumptions are in question. The maximum and minimum depths of soil covers have been defined according to the results obtained by the Ring Compression theory. The effects of depth of cover in Soil-Steel bridges were evaluated using finite element computer modelling according to the US 5400 The original design results and the results of finite element analysis were compared. The structural stability of the existing bridges with respect to the different fill heights was determined. The Ring Compression and Finite Element Methods results are compatible for higher depth of covers The stresses of the steel structure for defined maximum and minimum depth of cover, at the ultimate limit state conditions are less than the crushing strength of the steel. Butt further buckling analysis should be considered because the corrugated steel structure vulnerable to buckling failure