Finite Element Modeling of the Structural Response of a Reinforced Concrete (RC) Box Culvert with Edge Beam and Skewness

Abstract

Reinforced concrete (RC) box culverts are buried in structures installed under highways for various purposes, primarily for water flow. Usually, non-skewed culverts are preferred, but in areas with topography that require skewed culverts, cast-in-place RC culverts may be considered. Researchers have extensively investigated the structural performance of the non-skewed culverts.  Limited research studies are available to understand the structural behavior of RC-skewed culverts. Therefore, this study examined the impact of a skew angle in the top slab on the structural response of an RC culvert provided with an edge beam. Finite element modeling  (FEM) was employed to simulate RC culverts using a shell element model with varying skew angles of 0, 15, 30, 45, and 60 degrees in Abaqus. A solid model was introduced to confirm the shell model’s limitation of capturing localized failure in the edge beam. It is observed that the culvert’s edge beam with adequate shear reinforcement is essential to maintain its ultimate capacity. The study establishes a finite-element-based approach for evaluating load-deflection response in skewed culvert systems, supported by solid-element modeling to examine localized effects. The results provide a consistent basis for comparison across configurations, with emphasis on relative response trends rather than absolute prediction of ultimate capacity.