The weight of the soil overburden. For deep fills, the "soil-structure interaction" may reduce the effective load.
Basis of structural design, defining load combinations and partial factors. box culvert design calculations eurocode 2021
Actions on structures, specifically Part 2 for traffic loads on bridges. The weight of the soil overburden
Calculated based on a concrete density of approximately box culvert design calculations eurocode 2021
The pressure from water flowing inside the culvert, which can counteract external soil pressure.
Geotechnical design for soil pressures and bearing capacity. EN 14844: Specifically for precast concrete box culverts . 2. Design Loads and Actions
Designing a box culvert requires a multi-disciplinary approach using several Eurocode parts: