Note: Descriptions are shown in the official language in which they were submitted.
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DRAINAGE SYSTEM AND METHOD FOR INSTALLATION of DRAINAGE
SYSTEM
The present invention relates to a system for
draining a surface, such as for example football pitches,
sand volley and tennis courts, riding paddocks, golf
courses, playgrounds and other sports and recreation areas
or to create a pool or area of water suitable for a
skating rink for example. The system comprises a
watertight membrane and an integrated drainage system for
removing water in a controlled fashion which otherwise
would have had to drain into the ground. The system can
also include boundary wall components.
Background for the invention.
Arenas such as, for example, riding paddocks, sand
volley courts, football pitches and the like under the
open sky are subjected from time to time to rainfalls of
differing intensity. This can result in the area being
laid under water or at least becoming soft and unsuitable
for the intended purpose.
It is known to drain such arenas with trenches with
drainage systems comprising drain pipes covered by filter
cloth and hard core material, such trenches running in
both directions along and across the area in question.
However sand volley courts for example are often built for
shorter periods, in such cases a more or less permanent
drainage system is not very practical.
A membrane with an attached filter cloth is also
known, allowing water to filter through the cloth whilst
fine material and particles are held back.
These known methods have the disadvantage that
draining is often insufficiently effective, that costs are
high and that periodic maintenance is necessary since fine
material has a tendency to block the drainage system.
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There is therefore a need for a simple drainage
system making it possible to establish areas as dry as
possible without large and comprehensive building works
and where the need for maintenance is reduced. There is
also a need to reduce the cost of such installations.
Summary of the invention
One objective of the present invention is to provide
an improved drainage system for arenas giving a dry
surface even during heavy rain.
Another object of the invention is to provide an
improved drainage system not requiring extensive building
works prior installation.
A further object of the invention is to provide a
drainage system which, by simple means leads water away
from the arena in question in a regulated and controlled
fashion.
A further object of the invention is to provide a
drainage system which is simple to establish and has a
reduced need for periodic maintenance.
An additional objective has been to provide a
drainage system which is easy to dismantle so that the
installation is quick to dismantle and re-erect on another
site for either permanent or temporary use.
Another objective of the present invention is to
provide a drainage system which is inexpensive to produce
and where the site preparation costs are low.
Yet another objective is to provide a method for the
installation of the system, the said method making
installation easy and esthetically attractive.
A further objective of the invention is to ensure
that the filter cloth and drainage membrane do not
unintentionally loosen from each other and/or from an
eventual surrounding edge.
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Another objective of the invention is to provide an
underlying system having resilient and shock absorbing
properties, particularly but not exclusively for football
pitches and riding arenas.
The objectives of the present invention are achieved
by a system described in more detail in the independent
patent claim. Different types of embodiments based on the
invention are defined in the dependent patent claims.
According to the invention a watertight barrier, for
example in the form of plastic sheets or membranes, is
laid in an overlapping pattern so that between two rows of
such sheets or membranes a drainage channel is provided
which is preferably in fluid connection with a drainage
channel along the area's periphery. Furthermore, a
stabilizing cellular mat is applied, resting on the
previously mentioned sheets or membrane and is open in the
vertical direction but with walls in a sideways direction.
This stabilizing cellular mat is filled with a material
with good drainage properties and is preferably made from
non-woven fibers.
According to another form of application along at
least one side of the arena and in connection with the
previously mentioned watertight membrane an edging profile
rising up from the membrane and arranged to form a
watertight connection between itself and the membrane.
Furthermore this edging profile is formed in such a way as
to hinder any vertical or horizontal movement of the
watertight membrane when connected to the profile thus
locking the membrane in place.
In another embodiment the edging along the side or
sides of the arena can be formed as a hollow oblong shaped
body with a base plate and a U-shaped body connected to
this base plate.
In another form.of the invention the oblong shaped
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hollow body is hinged to the base plate so that the hollow
body can swing along a line which lies along the non-arena
side of the profile.
The hinge connection can preferably be in the form of
a lengthwise bead on the base plate onto which a
corresponding lengthwise groove on the hollow portion can
be clipped.
The base plate and the oblong, hollow element
described can preferably form an integrated unit where the
hinge connection is in the form of a reduced section so
that the hollow element can swing on this lengthwise
reduced section.
The watertight barrier can preferably be locked in
place by a leg on the hollow body the bottom of the leg
being bent right angles to the leg itself and where the
distance between this horizontal portion of the leg and
the base plate corresponds to the height of the studs on
the watertight membrane. The studded membrane is thus
locked in position along its length when this hollow
section is installed.
A means of locking the oblong hollow section to the
base plate and the membrane to the side can be
incorporated.
The same hollow section can be formed with at least
one channel in a lengthwise direction to hold advertising
panels, safety equipment, marking tapes etc.
One or more additional elements can be attached to
the top of the upper section in order to raise the height
of the perimeter wall.
During installation of the drainage system the
membrane can be locked in position along at least one edge
by inserting the membranes free edge into the perimeter
wall system and locking it, using the locking system
incorporated in the hollow oblong section comprising the
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perimeter wall.
Short description of the drawings
Embodiments of the system in accordance with the
5 present invention will be described in more detail with
reference to the drawings where:
Figure 1A shows schematically an arena with membrane
sheets and drainage channels according to the invention,
seen from above before the drainage material has been
applied;
Figure 1B shows a section of an arena, for example
for riding, with membrane and perimeter boundaries
according to the present invention;
Figure 2 shows in perspective and part a vertical
section through an alternative embodiment of the present
invention;
Figure 3 shows a vertical section through an
alternative embodiment of the perimeter edging profile
according to the present invention;
Figure 4 shows a vertical section at A-A, see Figure
1B, through the membrane and the perimeter boundary
profile according to the present invention;
Figure 5 shows an enlarged vertical section marked B
in Figure 4;
Figure 6 shows a view of adjacent membrane sheets
according to the present invention seen from above;
Figure 7 shows a vertical section through one
embodiment of a joint between two adjoining sheets
incorporating a drainage channel seen along line A-A
Figure 6;
Figure 8 shows a vertical section through an
alternative perimeter boundary intended to surround at
least part of, for example, a football field;
Figure 9 shows a vertical section through another
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embodiment of perimeter boundary according to the present
invention designed for coupling to a standardized drainage
pipe;
Figure 10a shows a vertical section through an
alternative design of a drainage channel for use between
two adjoining drainage sheets;
Figure 10b shows a vertical section through an
alternative embodiment of end joint and/or edge;
Figure 11 shows an assembled drainage system
intended to lie between adjoining sheets and drainage
channels; and
Figure 12 shows schematically a system for the
collection of drainage water coming from the system via
the drainage channels.
Detailed description of the invention.
Generally, Figures 1A and 1B show schematically an
arena seen from above. The arena 10 where it is important
to drain away water has a foundation of, for example,
gravel or a layer of concrete or asphalt. At times it is
complicated to ensure sufficiently good drainage of
rainwater and surface water from such an arena. Such
arenas can be permanent or temporary for use as sand
volley courts, riding arenas, football pitches, skating
rinks etc. In order to ensure good drainage watertight
membranes or sheets 11 of a plastic material are laid on
the substratum, such membranes or sheets having a degree
of stiffness so that they can lie with an even slope
towards a drainage channel. In connection with these
sheets a channel system 56 consisting of channels running
in the lengthwise and/or crosswise direction of the arena.
Suitable fittings are used for joining together the
channels leading the water out. The water is lead through
the channels in a direction indicated by the arrows in
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Figure 1A. The sheet 11 is preferably formed with upward
rising studs 12 arranged in a pattern. On top of the studs
12 is either glued or welded fast a filter cloth 13 of a
construction which allows water to pass through whilst
retaining fines, gravel, sand, earth and the like. Onto
the filter cloth 13 a layer of sand, earth or similar
material is laid depending upon the arenas intended use.
When it rains water will pass through the sand, gravel or
earth and down through the filter cloth 13 whilst the
materials above are held back. Water drains thereafter
onto sheet 11 and is lead away from the arena 10 to the
perimeter from where it is lead away through a connected
system of pipes.
In order to ensure that the layer of earth 14 is
kept in place and hindered from sliding or being washed
away from the arena 10 perimeter profiles 15 resting on
the ground are positioned round the arena and rise above
ground level to a height preferably but not necessarily
higher than the height of the layer 14 of sand, earth or
the like. Where large areas are to be covered sheets are
laid in overlapping lengths so that a continuous and
preferably watertight membrane is formed on the ground 16.
In this connection see Figures 2, 6 and 7, the studs 12,
in this connection together with the jointing profile 31,
can according to the invention be used to position and
hold two adjoining sheets 11 in place.
Perimeter edging 15 can be formed from a series of
similar sections put together to form, with the help of
corner profiles 32, a continuous edge 15 round the whole
of the arena 10. The ends of each section can for this
purpose be made interlocking, alternatively jointing
sockets can be used together with corner profiles 32. Such
jointing sockets being made so that the sections entering
these do so as to form a connecting joint without sharp
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edges.
Figure 2 shows in perspective part of a vertical
section through an arena 10 of the type mentioned above
with football pitches or tennis courts as typical
examples. When laying such an arena 10 a level substrate
40 must first be established. If it is desirable to
protect the area from cold or heat an insulating layer 41
of firm material for example expanded polystyrene is laid.
Thereafter studded membrane sheets 11 with welded filter
cloth 13 are laid according to the invention. The sheets
11 with filter cloth 13 are laid in an overlapping pattern
so that a more or less watertight joint is formed between
the adjoining sheets 11. The filter cloth 13 can for this
purpose be stretched sideways longer than the studded
sheet 11. Along the arenas 10 perimeter edge profiles 20,
to be described in more detail under, are employed. On top
of the sheets 11 with filter cloth stabilizing mats 42 of,
for example, non-woven polypropylene or polyethylene fiber
are laid and filled with earth or a gravel containing
material 44. The mats can have a height of, for example 5,
10 or 15 cm and can be filled with a material with good
drainage characteristics but not necessarily with good
sideways stability such as shingle. Alternatively ordinary
drainage material can be used. The object of using
stabilizing mats is to achieve a sideways stabilizing of
the materials whilst maintaining good vertical and/or
horizontal drainage. The sections 42 can, with advantage,
have hexagonal shape since this gives a stabile solution
and since the sections can be also supplied in ready made
mats into which the earth or gravel containing material 44
can be filled after laying. Even though a hexagonal shape
is preferred other shapes for example triangular, square
or many sided are possible. The object of the sections 42
is to establish a stable base for the top layer 43 and to
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simplify laying so that a plane underlay for the top layer
43 is established in an efficient way. Additionally this
type of solution makes it possible to use less material
which increases the drainage effect and contributes to
quicker draining and easier application of the materials.
Fig.3 shows a vertical section through an
alternative design of an edge profile 20. This edge
profile 20 is designed with a straight, vertical wall 45
configured to face inwards towards the arena 10. The
profile 20 comprises two separate parts which together
form edge profile 20. The upper part can preferably
consist of a hollow, closed portion 46 where the lower
part has a longitudinal groove 47 stretching along the
whole length of a side and constructed to function
together with a tongue on the other element 48 so that a
hinge acting lower edge is established. The bottom end of
the profile 20 functions as a drainage channel for leading
away water flowing from the top side of the sheet 11.
Instead of a horizontal base the bottom of channel 55 can
also be formed as a continuation of the circular shape for
which space must be made in the underlying ground. An
opening at the bottom of the profile 52 is formed by the
upper and lower lips 53 and 54. The opening communicates
with the internal channel 55. When installed the edge of a
sheet 11 is inserted in the opening 52 and is held in
place by the lips 53,54. In this way water which trickles
along sheet 11 enters the profile and can be lead out
through channel 55. When the sheet 11 is pushed into the
opening 52 the inner wall 45 is forced upwards since the
tongue and groove joint 47,56 acts a sprung hinge. To
ensure a good grip the height of the opening 52 can be
somewhat less than the height of the sheet 11 thus
establishing a downward gripping pressure.
It should be mentioned in this connection that this
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profile can be made in one piece as shown in Figure 3.
As indicated the profile has a sloping side 49 and a
top surface 50 which has a lengthwise slit 51. This slit
can be used to fasten advertising boards or other material
5 designed to stand up from perimeter profile. Alternatively
the slit 51 can be used to fasten a protective sheet to be
drawn over the arena when this is not in use. The slit 51
can also be used to fasten marking lines to divide the
arena in sections for a particular sport.
10 Figure 4 shows a vertical section through another
embodiment of the perimeter wall 15 seen along line A - A
in Figure 1B. Preferably the wall 15 rests freely on the
substrate (not shown) without being fastened to it.
Alternatively the perimeter wall 15 can be fastened to the
substrate so that it can move neither vertically nor
transversally. Any suitable fastening method can be chosen
for example by making the periphery wall 15 with a flange,
preferably on the opposite side to that facing the arena,
which can be anchored to the substrate with spikes.
According to the present invention the perimeter
edge 15 also has a function to drain water running along
sheet 11 away from the arena 10. To ensure that this water
is led away the perimeter edging 15 and the sheet 11 with
filter cloth 13 are designed to form a watertight
connection between the edging 15 and the sheet 11.
As shown in Figure 4 the perimeter edging 15
incorporates a base plate 17. This base plate can stick
out sideways either inwards towards the arena or outwards
away from the arena or in both directions. The base plate
17 can, on the side away from the arena, have a vertical
wall 18 stretching the whole length of the perimeter
edging and having a beading shaped top 19. The base plate
17 can be shaped to form a channel under the perimeter
edging 15 to lead away collected water.
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In. addition to the base plate 17 the perimeter
edging 15 also comprises an upper part 20. This upper part
can have an inverted U-shape where the open end of the U-
shape faces downwards towards the base plate 17. This
upper body can preferably be hinged to the base plate
along the edge on the base plate facing away from the
arena so that this upper body can be swung up from the
base plate 17 along this outside edge. In order to make
this hinge connection possible the lower edge on the side
of the section 20 facing away from the arena 10 is
provided with an open downward facing longitudinal pocket
21 shaped like a Y. This longitudinal pocket 21, open
underneath, is designed to snap onto the longitudinal bead
19 along the top edge of the vertical section 18 of the
base plate 17.
As is also shown in Figure 4 the upper body 20 can
be formed as a hollow, separate, closed body 22 running
the whole length of the perimeter wall 15. In the form
shown in Figure 4 this hollow body 22 is an integral part
of the upper body 20. It should be noted that this hollow
body 22 can also be formed as a separate unit which can be
fixed on top of the upper body 20. In yet another
embodiment the height of the perimeter can be further
increased by mounting additional units (not shown) on top
of the upper body 20 or on the hollow body 22. The upper
body 20 or alternatively the mounted or integral hollow
body 22 can, along at least the side facing the arena 10,
be formed with a channel 23. The upper body 23 can also be
formed with longitudinal channels on top and/or on the
side facing away from the arena 10. The profile(s) 23 can
be used to fasten markings for sand volley ball courts,
safety cushions, advertising material and so on. The
inward facing channel can also be used to fasten a cover,
which can also be watertight, to draw over the court 10
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when it is not in use to protect it from, for example,
leaves, animal excrement or snow.
As is also shown in Figure 4 the base plate 17 and
the upper body 20 have the same cross section and shape
along their whole length. These two bodies 17 and 20 are
preferably extruded in a plastic material such as a
composite material for example but not exclusively WPC
(Wood Plastic Composite) or in another suitable plastic
material. Alternatively, the base plate 17 can be extruded
or made of a stiff solid material whilst the upper
portions or components can be made from a softer material.
However, it should be pointed out that the base plate 17
and/or the upper body 20 can be made of wood, plastic,
glass fiber reinforced polystyrene, metal such as
aluminium or similar materials. The upper closed body 22
can be designed so that it can be filled with a material
to give extra weight such as water or sand. In such a case
can each perimeter wall section be given closed ends (not
shown) and openings for filling or emptying the above
mentioned material.
In accordance with the design shown in Figure 4 the
base plate 17 is flat. This solution is, for example, well
suited to use on a hard surface such as asphalt, concrete
or similar, preferably on a level surface which is more or
less self-draining. It should be noted however that the
base plate in conjunction with, for example, a gravel
substrate where it is not so easy to drain away the water,
can have a concave shape which forms a drainage channel
for removal of water along the base of the perimeter wall
15. In order to lead the water away the base plate 17
and/or the lower end of the perimeter wall 18 have holes
(not shown) which are connected to a pipe (not shown)
which carries the water away from the arena 10.
In order to establish a drainage system in
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accordance with the invention a sheet 11 with studs 12 is
laid in an overlapping pattern with the studs 12 of the
underneath sheet being covered by the corresponding void
in the overlapping sheet 11. The filter cloth 13 is a
little wider than the sheet 11 to which it is attached, so
that the filter cloth 13 can also overlap..At the same
time as sheet 11 is laid a section of perimeter wall 15 is
also laid so that an end of sheet 11 can be entered into
the base plate 17. To make this possible the upper part 20
is swung on the hinge connection. When the end of the
sheet 11 is in position on base plate 17 the upper part 20
is swung back into position. The inner edge 24 continues a
short vertical distance beyond the horizontal foot 30
(Figure 5) and onto a stud thus stopping any lateral
movement of the sheet 11 out of the base plate 17. In
order to avoid this edge 24 jumping up again and thereby
losing-its locking function the upper part 20 can be
locked to the base plate 17 by a locking arrangement (not
shown). In the design shown in Figure 4'locking is by a
20' screw or bolt from a recess 29 and protected by it,
entering into part 27 of the base plate 17 and holding the
upper body 20 in place. Alternatively the upper part 20
can be clicked into place by the provision of suitable
extruded bead and pocket elements.
To ensure a stiff connection between the perimeter
wall 15 and the sheet 11 a horizontal part 30 of the upper
body 20 is arranged to clamp in position on the top of the
studs 12 so that a stable connection is established
between the perimeter wall 15 and the sheet 11. The
horizontal plate 30 is arranged somewhat above the inner
end edge 24 and is configured to rest against the surface
25 of the studs 12, so that a stable, locking connection
between the perimeter wall 15 and the plate 11 is
established. According to the invention the sheet 11 is
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thus prevented from moving vertically or horizontally out
of the perimeter wall 15.
As indicated in Figure 4 all the elements
constituting the perimeter wall 15 such as the vertical
wall 18, the beads 19, the Y-shaped pocket 21, the recess
29, the horizontal plate 30 etc. run lengthwise making the
perimeter wall suitable for extrusion.
Although the hinge shown in Figure 4 is of a beading
and pocket construction which is snapped on the beading 19
the hinge can take other forms for example a thinner, more
flexible longitudinal section along which the upper body
can be turned in relation to the base plate 17. In such
case the upper part 20 and the base plate 17 will be one
unit and not two as shown in Figure 4.
15 Figures 6 and 7 show schematically a joint between
two sheets 11 where one sheet has a flap along the edge 16
which overlaps the joint. Figure 6 shows two sheets 11
seen from above whilst Figure 7 shows a vertical section
through the joint at A-A in Figure 6. As shown in Figure 7
20 a jointing profile 31 is used, made to lie in a shallow
trench (not shown) in the ground. Jointing profile 31
consists of a base plate 33 intended to lie on the bottom
of this shallow trench. Each side of this base plate 33 is
formed as an S 34 with a horizontal supporting surface 35.
A centrally positioned column 38 rises up from the base
plate 33 to form a central support for a jointing plate 36
designed to tie together the studs on the sheets 11 on
each side of the profile 31. For this purpose the plate 36
is equipped with downward facing edges 37. The jointing
plate 36 is wide enough to encompass the first row of
studs on the sheets 11 on each side of the jointing
profile. The jointing profile 31 is stiff enough to
support the sheets 11 and forms at the same time one or
more longitudinal channels 39 which lead away the drainage
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water along the length of profile 31.
Figure 8 shows a cross section of a perimeter wall
or edge 15 for a football pitch 10. The height of such a
wall can be for example 5 - 15 cm. The perimeter wall or
5 edge 15 has three main functions namely i) to contain the
material on the inside ii) to lead away the water draining
from the pitch along the sheets 11 and iii) to function as
a support for advertising placards, protection mats,
fencing posts etc. The perimeter edging 15 is made with a
10 channel 43 designed to receive a fin 54 on a channel
shaped body 44. This channel shaped body has a
corresponding fin 54 which, together with the fin or edge
53 on the perimeter edging 15 is designed to clamp the
sheet 11 with filter cloth 13 so that water running along
15 sheet 11 is collected in the channel 44 to be thereafter
led away from the pitch. Although the Figure 8 shows a
channel with a semi-circular shape the body 44 can have
any suitable shape for example square or rectangular.
Figure 9 shows another embodiment of a perimeter
edge 20 according to the invention. In this case the
perimeter edging comprises, in relation to the arena 10,
an outside element 49, an inside element 45 and a third
element 48 which forms the bottom of the drainage channel.
These three elements 45,48,49 are designed so that
together they form a perimeter wall unit as shown for
example in Figure 3, that is to say with a drainage
channel and a recess 51 for fastening, for example,
advertising placards.
Figure 10a shows schematically a cross section
through a drainage channel designed to lie between to
adjacent sheets 11 with filter cloth 13 where the channel
is intended to lie in the lengthwise direction of the
arena and where at least one end is connected to a further
channel in the perimeter wall 20.
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Figure 10b shows schematically a vertical section
through an alternative embodiment of a joint and/or edge
according to the invention. According to this embodiment
the perimeter edge is in the form of a channel 55 arranged
along one edge being provided with to sideways and
outwards extending fins 56, extending along the entire
length of the body and being designed to lock the plate
11. Between said fins 56 an opening is formed, and since
such embodiment is made of one integral body, the circular
or oval shape will produce a clamping force.
Figure 11 shows schematically an embodiment of a
channel system built up of elements shown in Figure 10
where sockets of different sizes are used whilst Figure 12
shows a collection system including a collection tank 57.
Drainage water is led from the arena 10 and led to the
collection tank 57 through the drainage channels. The tank
57 is equipped with a pipe 58 through which water can be
pumped back to the arena 10 when this is desirable because
of drought or when the surface requires watering. For this
purpose the piping system is equipped with a pump 59 and
valves (not shown).
In a solution according to the present invention
water on the arena or falling as rain or melting snow or
ice sinks through the surface material of the arena and
down through the filter cloth 13. Since the sheet 11 is
watertight the water will run along the sheet out to and
into the perimeter walls 15. Thereafter the water will run
inside the perimeter wall 15, along its length and out to
a drain (not shown) leading to a cistern or tank 57.
The membrane according to the invention can be
delivered as more or less stiff sheets or in roll form.
The membrane can, according to the invention, be
further equipped with fins, grooves and other profiles or
patterns to ensure that the membrane lies firmly and
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safely on the substrate and which hinder displacement of
the membrane sheets during the construction phase.
It should also be noted that the invention can also
be applied in connection with ice rinks where the membrane
lies on a substrate, cooling pipes are laid between the
studs of the membrane with filter cloth and then covered
by a layer of gravel or similar material.
The membrane should preferably be thick enough to be
robust but nevertheless easy to handle, for example
delivered in rolls.
Advertising boards previously mentioned can for
example be made in aluminium and can be fastened to a
groove in the upper part of the perimeter wall and
thereafter bent towards the spectators.
The invention is also suitable for use in connection
with skating rinks where a controlled and quick method of
removing the water from melting ice is needed. The
invention is also suitable for use where damage to the
substrate due to sudden, unexpected and large quantities
of water is to be avoided.
In order to lock the edges of the watertight sheets
to the channels 44,55 wood screws can for example be used.
These are screwed through the upper flange 54 and sheet 11
and into the lower flange 56. Similarly screws can be used
to fasten the edges of the sheet 11 to the flanges 53,54
on the edge 20.
