Underslab - BWT P-PSC Notice D'installation Et Conseils D'utilisation

4.

UNDERSLAB

NOTE:
THE UNDERSLAB MAY BE POURED AFTER THE PANELS ARE MOUNTED
In this case, the panel structure is positioned, level, on 10 cm blocks after careful tracing and
impeccable alignment of the various components.
Upon pouring the slab, the concrete flows under the panels and encases the supporting braces.
Finish by pouring concrete behind the panels, directly at the feet of the supporting braces to form
the lower ring beam. This method is recommended as it increases the strength with which the
supporting braces are held in position. Furthermore, using this method there is no need to install
formwork 10 cm outside the pool dimensions to delimit the lower ring beam.
THE BASE OF THE EXCAVATION:
Finish the base carefully by hand using a spade and a pick.
Check depth measurements from surface reference points using a spirit level, flat rule, and plumb
line.
LAY THE BASE COURSE:
Depending on the under-lying soil, use one of (or a combination of)
the following:
- A BED OF STONES (diam. 5cm), evenly distributed.
- BLINDING CONCRETE, 5 to 10 cm thick matching the final shape
of the pool base (optional).
- A FILTER COURSE to prevent clay particles from rising up from
under-lying layers.
- A PROTECTIVE FILM or ANTI-TERMITE FILM.
FIT THE MAIN DRAIN:
Connect the main drain to its line (tube - pressure 10 bars, outer
diam. 50 mm, long enough to allow connection in the machine room) and bed it in the middle of the
lowest point. To hold the main drain in position, create a recess by hand and finish by fitting rebar
(6 or 8) staples. Protect the upper surface of the part using the protective cover provided with the
drain to prevent soiling.
The upper surface of the main drain should be flush with the finished surface of the
underslab (slab + any finishing screed).
caution, never install a main drain less than 30 cm from the Pool wall
POSITIONING THE WELDED WIRE MESH:
Steel welded wire mesh, lattice 10 x 10 x 4 (or a double layer of 20 x 20 x 4).
Roll the mesh out over the surface of pool base. Ensure that it is not flattened against the floor of the
excavation so that it may be correctly imprisoned WITHIN THE CONCRETE when the underslab
is poured. Use "L" shaped iron bars to grip the mesh, raise it and position it at about 2/3 the depth
of the underslab.
Sections of mesh should overlap by 20 to 30 cm and should be tied together.
Note: If fibreglass reinforced concrete is used do not reinforce with a welded wire mesh.
PISCINES P-PSC 2020/05 - Indice de révision : B - Code : 37101
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