: Horizontal earth pressure due to live load surcharge (typically to ).
Given (assumed typical): span clear = 3.0 m, internal height = 2.0 m, slab/wall thickness = 0.3 m, fill depth above slab = 1.2 m, γ_concrete = 24 kN/m3, γ_soil = 18 kN/m3, φ = 30°, ko = 1 − sin30° = 0.5, LM1 wheel load 150 kN dispersed through 2:1. box culvert design calculations eurocode 2021