On a box culvert:

Hand calculation approximation (simplified frame method):

Box culverts are essential hydraulic structures used for drainage, underpasses, and utility crossings. The transition to Eurocode 7 (Geotechnical design) and Eurocode 2 (Concrete design) – with national annexes – has standardized design across Europe. The 2021 updates (primarily amendments to EN 1992-1-1 and EN 1990) introduced refined load combinations, durability requirements, and sustainability considerations. This article provides a robust framework for box culvert design calculations Eurocode 2021, covering loading, structural analysis, reinforcement design, and serviceability checks.