Enter the inside length, width and depth, the wall and floor thicknesses and, for a tank, the cover slab. PRAXAO works out the capacity, the excavation with its working space, the blinding and structural concrete, the formwork, the steel and the inside lining. The drawing shows the box in 3D, in plan and in section. Thicknesses, working space and steel ratio are starting values to replace with the drawings.
Enter the dimensions to see the drawing.
Fill in the fields to see the result.
Preliminary estimate from the values entered: not a structural validation and not an execution plan. Check the local rules and the manufacturers’ data.
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Capacity: 24.00 m³ · Capacity in litres: 24000 · Excavation: 53.46 m³ · Blinding concrete: 0.75 m³ · Structural concrete (walls, floor, cover): 11.16 m³ · Formwork: 71.20 m² · Steel: 892.48 kg · Inside lining or waterproofing: 40.00 m²
No. It counts what a set of dimensions requires. The wall thickness against earth and water pressure, buoyancy, the reinforcement and the watertightness details come from the engineer.
Walls: the outside footprint minus the inside footprint, times the depth. Floor and cover slab: the outside footprint times their thickness. The blinding concrete is counted apart.
It is a starting value in kg of steel per m³ of concrete. Replace it with the figure of the engineer’s schedule: the steel weight is only as good as that ratio.
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