| Parameter | Value / Design decision | |------------------------|--------------------------------------------------| | Cover depth | 1.2 m soil + asphalt | | Slab thickness | 300 mm | | Concrete grade | C30/37 (XC4, C1 strength) | | Steel grade | B500B | | Top slab main reinf. | H12 @ 150 c/c (top and bottom) | | Side wall reinf. | H12 @ 150 vertical faces (inner/outer) | | Shear links | H10 @ 150 mm (near supports) | | Crack width (SLS) | 0.22 mm (w_max allowed 0.3 mm) | | Bearing pressure | 133 kPa ≤ 210 kPa (OK) | | Buoyancy safety factor | 1.35 (OK for accidental) |
To guarantee durability throughout a typical design life of 50 to 120 years, SLS checks are mandatory under Eurocode. Stress Limitation (Clause 7.2)
Assuming pure bending for conservative approximation at midspan: box culvert design calculations eurocode 2021
σc≤0.60⋅fcksigma sub c is less than or equal to 0.60 center dot f sub c k end-sub
Defines traffic load models (LM1 to LM4). | Parameter | Value / Design decision |
The vertical load from the top slab, walls, and self-weight must be balanced by soil pressure underneath the bottom slab. In basic calculations, a linear uniform soil pressure distribution is assumed:
: Specifically addresses precast concrete box culverts, covering manufacture and installation. Stress Limitation (Clause 7
Top Slab Weight=Thickness (m)×25 kN/m3Top Slab Weight equals Thickness (m) cross 25 kN/m cubed
