Abstract: Box culverts are the structures constructed below highways and railways to provide access to the natural drainage across them. The opening of the culvert is determined based on the waterway required to pass the design flood, whereas the thickness of the culvert section is designed based on the loads applied on the culvert. Culverts and bridges often serve the same purpose; however, they differ on the size of the structure. Box culverts are ideal for flows where hydraulic head is limited. For an equivalent waterway area to circular pipes, box culverts can be configured to have less impact on upstream water levels and downstream flow velocities than equivalent pipe structures. This report devotes to the box culverts constructed in reinforced concrete having different aspect ratios. The box culverts are analyzed for varying cushion and no cushion loading. The main emphasis is given to the behavior of the structure under the types of loading as per IRC codes and their combinations top produce worst effect of loading for safe structure. Comparison and conclusion are made on the basis of maximum bending moments shown for different loading cases.

Keywords: Aspect ratio, Bending Moments, IRC, Cushion, Earth pressure, Surcharge loading.