DESIGN CONSIDERATIONS AND SPECIFICATIONS

1. Design loading requirements for Giant Segmental Box Culvert (GSBC) are in accordance with :
   BS 5400 : Part 2 : 1378 modified by (b).
   Department Standard ED 31/87, Buried Concrete Box Type Structure, issued by Department Transport (UK) Highway and Traffic.
   JKR LTAL (Long Term Axle Load) and SV (Special Vehicle) requirements.
2. Reinforced concrete design in accordance with BS 5400 : Pt.4, 1984.
3. Concrete characteristic strength at 28 days, fcu = 30 Mpa - 40 Mpa.
4. Concrete cover to reinforcement for GSBC = 30mm.
5. Soil parameters used in design :-
6. Coefficient of the earth lateral pressure at rest = 0.5, bulk density of soil = 19 kN/m3
7. Hume's GSBC also complies with proof test load criteria with 2 nos, of 112.5kN loads over an area of 500mm x 150mm, spaced at 1.8meter intervals, placed at any position on the upper unit of the box culvert.
8. Hume's GSBC is designed to cater for backfill superimposed dead load not exceeding 4 meters depth (inclusive of pavements) plus 45 units of HB vehicle primary live loads.
9. Hydrostatic pressures are eliminated by the provision of a series of 50mm diameter weep holes placed along the centerline of the invert wall.