Tricel Vitae UK6, Техническое руководство

Страница: 15 / 40

15
Step by step – installation procedure
Steps
Installation required (post-excavation)
Gravel Concrete
Installation
of the tank
base:
1
Remove any soft spots or large stones and boulders.
2
The base is constructed of a 250mm
layer of suitably compacted gravel.
The base is constructed of a 50mm layer
of suitably compacted gravel, covered
with a 250mm layer of semi-dry
concrete.
3
Ensure that base is level and at the correct height to accommodate the
incoming pipework.
4
It is important to maintain a completely
dry excavation until the final pour of
concrete is set. It may be necessary to
line the excavation with a continuous
layer of 1200-gauge polythene to
maintain the integrity of the concrete.
How to
position the
tank on to
the base:
5
Mechanically lift the plant carefully
into the centre of the hole and place
on the prepared base.
Mechanically lift the plant carefully
into the centre of the hole.
6
The plant must sit level on the base.
7
Connect and seal the pipework to the tank.
Backfilling
around the
tank:
8
Ballast the plant by filling each chamber with clean water to a depth of 300mm
and recheck the pipework levels.
9
Commence backfilling with gravel in
layers of 225mm evenly around the
tank ensuring that there are no voids
until gravel has reached 50mm over
the cylindrical body of the tank.
Compact each layer in succession. *
Commence backfilling with concrete in
layers evenly around the tank, ensuring
that there are no voids until it has
reached the outlet invert. Continue
backfilling with gravel, until it has
reached 50mm over the cylindrical
body of the tank. *
Note
* Continue filling the chambers with water while backfilling, ensure that the rising
water level is no more than 300mm above the backfill level.
10
Mount and seal manhole risers (if required). Please refer to section 5.10,
‘Risers.’
11
Complete backfilling with topsoil up to the max ground level. Allow for
subsequent settlement of topsoil.
Note
The use of geotextile barrier fabrics over the gravel backfill is considered good
installation practice. The fabric must be chosen to allow the flow of water in and
out of the excavation but to prevent the movement of fine soil particles into the
gravel backfill.