Two-Dimensional Analysis of Invert Paving of Deteriorated Steel Culverts

This paper presents two-dimensional finite element analysis performed on corrugated steel culverts, whose inverts are badly deteriorated and treated with concrete paving for rehabilitation. In the study, the culvert analysis and design software (CANDE) was employed to perform the plane-stress analysis of the buried circular pipe and pipe-arch culverts. Thrust, bending moment, and deflection responses of the deteriorated culverts were compared with those of the invert-paved culverts. For each computer simulation, a half-mesh was constructed at level 2 CANDE and then imported into level 3 CANDE to use its versatility. An extreme deterioration with 95% metal loss was simulated by introducing reduced cross-sectional properties (thickness and modulus of elasticity) over the bottom portion as opposed to the remaining part of the culverts. Similarly, concrete paving was simulated while assuming the culvert invert consists of concrete alone. The results showed that through invert-paving deflections decrease and thrust force becomes more uniform while bending moment increases over the invert. While this plane-stress analysis may not be able to sufficiently predict the actual responses of metal culverts in the field, it can serve as a rapid analysis tool to understand the structural benefits that a local improvement made over the invert can offer to the entire culvert structure.