Note: Descriptions are shown in the official language in which they were submitted.
BACKGROUND OF THE INVENTION
The presen~ inven~ion rela~es to a demountable, port-
able reservoir structure for holding large volumes of liquids
such as water and free flowing solids such as grain, and to a
method of erection of such a reservoir structure.
There i6 a real and continued need for a ligh-tweight,
low cost, portable reservoir system which may be quickly
erected and dismantled and stored, for example, when a town's
existing reservoir is closed down for maintenance or cleaning.
Use of such a system would ensure that the town inhabitants may
continue to be supplied with water for sanitary, drinking and
fire protection purposes. Because of the difficulties in
maintaining water service to a town while its reservoir is
being serviced or cleaned, veLy often such maintenance and
cleaning i6 neglected or delayed.
There is also a need for a portable reservoir
structure which may be erected and dismantled as required in
remote or frontier areas, for example where oil or mineral
exploration is taking place and where a temporary town site has
been established for those engaged in such operations.
The construction of temporary reservoirs, for example
for water, usually involves standard methodæ of construction
with the use of the usual building materials. Often standard
materials are not readily available and site preparation is a
problem. This is particularly true in earthquake or flood
,~
'7S~7~
devastated areas and in northern areas.
PRI0~ ART
.~
There have been few devices developed previously to
provide a lightweight, low cost portable reservoir system for
liquids ~hich could service ~he temporary needs of communities
or provide a reservoir sys~em whîch is readily transportable to
and erectable in remo~e areas. Two proposals for such
structures are set ou~ in GLeen U.S. Patent No. 3,460,705
issued August 12, 1969 and Levens U.S. Paten~ No. 3,819,079
issued June 25, 1974. Green describes and illustrates a
demountable storage container which has a cylindrical shell
formed of a plurality of detachably connected panel members and
a flexible liner member positioned within the shell. Levens
teaches a modular, portable tank shell and tank that can be
readily erected and dismantled, having an outer shell forming a
generally circular enclosure with an innerO flexible liner.
Inlet and outlet pipes service the tank. The panel members of
Leven6 and Green are both curved to conform to the periphery of
the circle formed by the tank, and are secured directly ~o each
other by a hinge-like mechanism in the case of Levens, and by
bolts extending through the panels in the case of Green. Con-
siderable attention to detail in construction of the elements
of these previously described portable tanks is required, and
considerable time and care in assembling the components is
-- 2 --
~20'~'70
required by the workers constructing the tanks.
Other references of background interest describing
various constructions of storage tanks, some of which are
demountable and some of which are not~ include U.S. Patents
Nos. 2,684,173 of Schmitz issued July 20, 1954: 3,355,052 of
Kaups issued November 28, 1967; 3,471,053 of Endicott et al
issued October 7, 1969: 3,861,552 of Adams issued January 21,
1975; 3,880,315 of Nelson et al issued April 29, 1975;
3,917,104 of Rossitto et al issued November 4, 1975; 3,951,294
of Wilson issued April 20, 1976; 4,240,562 of Holschlag issued
December 23, 1980; and Canadian Patents Nos. 97,692 of Wright
issued February 27, 1906; 194,203 of Nissen issued November,
25, 1919; 560,253 of Tolcott issued July 15, 1958; ~67,707 of
Wiggins issued December 23, 1958; 623,230 of Lindstrom issued
July 4, 1961; 671,336 of Jones issued October 1, 1963; and
1,091,883 of Cazaly is6ued December 23. 1980. As well, Nelson
U.S. Patent No. 4,111,314 describefi and illustrates a trans-
portable storage device (silo) and Svensson Canadian Patent No.
636,339 issued February 13, lg62, describes a method of
erecting walls, for example, for a storage device. Again,
these references are of general background interest.
OBJECTS OF THE INVENTION
It is an object of the pre6ent invention to provide a
demountable portable reservoir structure which is capable of
7g~0
holding large volumes but which is ligh~weight and economical
in cost. It is a further object of the present invention to
provide a reservoir simple and quick to erect and take apart.
It is a further object of the present invention to provide such
a structure which has elements which permit containerization
and/or palletizing for easy and guick handling and
transportation.
SUMMARY OF THE INVENTION
According to the present invention there is provided a
demountable, portable reservoir structure having elements com-
prising:
(a) a plurality of flat, elongated base plates
connectable in a plane to form a ring;
(b) a plurality of similar, rigid wall panelæ, the
edges of which define rectangles, the wall panels
when in position to be vertically seated on the
base plates;
(c) means at the base of each of the wall panels and
on each of the base plates to position the wall
panels on the plate6 so that the area within is
enclosed when the panels are vertically oriented;
(d) column means to be positioned within the base
plates and wall panels and to rise above the top
edges of the panels when in position;
ds
~L;2V~9~7~
(e) a plurality of trusses to be supported by and
secured to, the column means and panels;
(f) a flexible liner to be connected to the inside
surfaces of the panels when in position, the
liner to provide an impermeable barrier on the
area circumscribed by the panels and base plates
to a height above the maximum level to which the
reservoir liquid is to come; and
(g) means enabling controlled liguid flow through the
~lexible liner when in position.
These elements are each releasably connectable to contiguous
elements in the structure and are of dimensions and weight to
permit containerization and palletizing for handling and trans-
portation. For most applications of the invention, it is pre-
ferred to also provide a flexible roof cover to be supported on
the trusses, the lower edges of the roof cover, when in
position, to circumscribe the upper, outer surfaces of the wall
panels and to be secured in that position.
As well, according to the present invention there is
provided a method of erecting a reservoir on a levelled surface
serviced with liguid inlet and outlet means. A plurality of
rectangular, s;milar rigid wall panels are mounted contiguously
and in verticaL orientation to form a ring. A vertical column
i6 centrally erected within the ring of wall panels, the column
rising above the top edges of the panel~. Using the column as
a scaffold, trusses are raised into position extending radially
-- 5
d~ 79 ~C~
outwardly from the column and supported by the panels and
column. ~n impermeable flexible liner, within which liquid is
to be retained is then fitted within the reæervoir on the sur-
Eace circumscribed by the panels, and secured in proper
5 position to the panels, the inlet and outlet means providing
controlled liquid flow through the liner.
In a preferred embodiment of the invention, the method
further comprises using the column as a support for a boom to
raise a flexible roof cover to the apex of the reservoir roof
trus6es wheLe it will be unfolded into position on the trusses
and will be supported by these trusses. The lower edges of the
roof cover, when in posi~ion, circumscribe the upper, outer
surfaces of the wall panels. ~'he roof cover is secured in this
position.
The reservoir system according to the present in-
vention is ideally ~uited to, although not limited to, the
holding of water. The present design lends itself to the
construction of reservoirs having capacities of from 100 cubic
metres to 1,300 cubic metres (Z5,000 Imperial gallons to
300,000 Imperial gallons). The structure has proven to be
easily transportable to remote areas and erectable by unskilled
laborers in relatively little time. Once erected, it has
proven reliable and capable of withstanding unusual stresses
such as high winds and snow load~.
~2~7g~0
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and advantages of the present
invention will become apparent upon reading the following
detailed description and upon referring to the drawings in
which:
FIGURE 1 is a side view of an assembled reservoir
structure according to the present invention;
FIGURE 2 is a partial plan view of connected base
plates for the reservoir structure and unconnected wall panels
ready to be mounted on the base plates
FIGURE 3 is a perspective view of a number of wall
panels for the reservoir stcucture in vertical posi~ion mounted
on the hase plates:
FIGURE 4 is a schematic side view of the central
support column of the present invention centrally mounted
within the reservoir structure walls, used as a support for a
boom for raising roof trusse6 into position;
FIGURE 5 i8 a half plane view from above of the
reservoir structure according to the present invention with
roof trusse6 in position;
FIGURE 6 is a schematic side view of the structure
according to the present invention with the roof covering being
raised into position;
FIGURE 7 on the second page of drawings is a detail
view, from the side, of the lower section of the column which
:~IL;20'7~'7~
is removable to enable positioning of the inner liner of the
reservoir; and
FIGURE 8 is a diametric section side view of the com-
pleted reservoir structure according to the present invention,
holding water.
While the invention will be described in conjunction
with example embodiments, it will be understood that it is not
intended to limit the invention to such embodiments. On the
contrary, it i8 intended to cover all alternatives, modifi-
cations and equivalents as may be included within the spirit
and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE DRA~INGS
In the drawings, similar features have been given
similar reference numerals.
Turning to FIGURES 1 and 8, there are illustrated
respectively a side view and a diametric section side view of
an assembled reservoir according to the present invention. The
reservoir com~ri6es a plurality of flat, elongated base pla~es
2 (FIGURE 2) which are individually connectable to other base
plates in a plane to form a ring 4 as illustrated in FIGURE 2.
The base plates are provided with hook shaped brackets 6
(FIGURE 3) of any appropriate con~truction, for a purpose which
will be described hereinafter, the hook brackets being
outwardly oriented, away from the center of the circle, when
JI~
base plates 2 are secured in circular position. Base plates 2
are secured together by means of connec~ors 8 which are bolted,
as can b0 seen in FIGURE 3, to the upper surfaces of adjacent
base plates. A hole lO is provided in the central part of each
5 of these connectors 8 to receive, as required, an anchor bolt
(not shown). It is preferred that connector~ 8 be pre-
attached, one to the corLesponding side of each plate, to
simplify and accelerate connecting together of the base plates
in the field. It is relatively easy ~o place the re~uired
number of these base plates into their required circle,
fastened together as above, and to shift them slightly i the
final plate doe6 not exactly close the circle. This plate
placin~ is aided by describing a circle of aepropriate radius
using the center of the centLal base plate as a turning point.
5 This completed circle (actually a polygon) assures tha~ the
wall panels will, when mounted on the base plates, exactly fit
to close the circle.
Forming the vertical, generally cylindrically shaped
wall of the re~ervoir are a plurality of similar, rigid wall
~ panels 12. The panels are preferably~ but not necessarily,
made of corrugated steel, the corrugations arranged in vertical
fashion when the panels are in position, and positioned so that
adjacent vertical edges of panels interlock on a vertical
tongue and groo~e seam. The base of each of the panels is
provided with base hinge bar 14, to the bottom of which are
secured two hinge pins 16. Base hinge bar 14 of each panel
'7~
fits between pairs of hook brackets 6 on each base plate, and
hinge pins 16 are seated at the base of the hook portion of
each hook bracket 6 when the wall panels are in vertical
orientation as illustrated in FIGURE 3. This assures proper
relative positioning of the wall panels. To the out~ide
surface of each wall panel 12 are secured upper ten6ion bar 18
and lower tension bar 20. The adjacent, corresponding tension
bars on adjacent wall panels 12 are secured together by
appropriate bolts through pairs of tension bar connec~ors 22.
It should be noted that the bolts used to connect the tension
bars are in double shear. The tigh~ness of the nuts on these
bolts is not important. Thus, the use of torque wrenches is
not required in this assembly. When thus connected, the
tension bars 18 and 20 form complete rings about the ~uter
surface of panels 12 to absorb approximately 90% of the
pressure exerted against the inside surfaces of the wall panels
by water contained in the reservoir. The remaining 10% is
taken by the cap angles 26 on the wall panels. As can be seen
in FIGURE 3, eye bolts 2~ are provided on tension bars 18.
At the top of each wall panel 12, as can be saen in
FIGURE 3, there is secured a wall cap angle 26. Adjacent wall
cap anglas of the panels, when in position, are secured
together by wall cap angle connectors 28.
On the inside surface of each wall panel 12 there is
preferably provided an appropriately sized rectangular panel 30
of insulation (FIGURE 8). For example, if the wall panels 12
-- 10 --
~l2~ '70
are 4 x 8 feet in outer diamensions, two foam insulakion panels
30 of 2 x 8 feet ou~er dimensions and three inch thickness may
be used. A minimum thickness of one inch insulation is
specified to keep the fabric liner from entering the
corrugations of the wall panels.
In ~he center of the area to be circumscribed by wall
panels 12 is positioned an appropriate column base plate 32 of,
for example, 3/8 inch steel (see, eg., FIGURE 2 or 7).
Appropriate apertures are pro- vided in the base pla~e for
liguid inlet and outlet pipes 34 and 36 respectively, and
connection means 38 for these pipes are bolted to the lower
surface of this column base plate 32 as illustrated in FIGURE
7. A third aperture is provided in column base plate 32 to
which is connected by appropriate connection means 38 an
overflow pipe 40 to remove overflow water from the reservoir.
To the upper surface of column base plate 32 is
secured column 42 (see, eg., FIGURE 4). This column is
concentrically positioned with respect to wall panels 12 and is
positioned, on the base plate, over the aperture leading to
overflow pipe 40. ~olumn 42 is made up of a base spool 44, a
lower section 48 and an upper section 50. The column sections
48 and 50 and base spool 44 are pipe section~ (eg. eiyht inch
diameter piping) with flanges at their ends. The lower flange
46 of base spool 44 is bolted to base plate 32. Lower section
48 and base spool 44, when in vertical position as illustrated
in FIGURE 8 provide a passageway for overflow water from the
3'70
reservoir into overflow pipe 40. Lower flan~e 52 of upper
section 50 and u~per flange 54 of lower section 48 are secured
together, but ~paced rom each other, by means of nuts
appropriately positioned on threaded rods 56 spaced about
flanges 52 and 54. This arrangement of bolts and thread rods
separates sections 48 and 50 and thus provides a space ~or
overflow water to enter lower section 48. As well it provides
a means for adjusting the height of column 42 and the vertical
alignment of upper section 50.
It should be noted that the upper portion of base
spool 44 and the lower portion of lower section 48 of column 42
are connected by hinge brackets 58. This enahles the
positioning of base spool 44 on column base plate 32 before the
upper part of column 42 is erected into vertical position, and
then the pivoting of sections 48 and 50 of columns 42 into
vertical po6ition once base spool 44 has been secured in
position on column base plate 32 (see FIGURE 4). Hinge
brackets 58 are relea6ably secured together. so that spool 44
may be disconnected completely from lower section 48 as
required to allow the placement of the fabric liner after the
erection of the reservoir structure and before the cover is
positioned.
Ladder rungs 60 are provided on the outer surface of
column 42 to provide access to the top of the column.
Supeorted by column 42 and the wall cap angles 26 at the tops
of panels 12 are a plurality of trus6es 62 (eg. FIGURES 5 and
- 12
:~2(~'7~
-
8). These trusses are secured at one end to an upper portion
of column 42 and at their other ends to wall cap angles 26. As
can be seen in FIGURE 5 the trusses extend radially about the
column and are spaced equally from each o~her about the
column. If Lequired, for example, where the reservoir roof
will carry heavy loads, the trusses are inter-connected by
appropriate braces 64 as illustrated in FIGURE 5.
~ the top of column 42 is secured a cap 66 (FIGURE
5), this cap and the upper edges of truss braces 64 providing
smooth surfaces for a flexible roof cover S~ which covers the
cap and preferably extends over the wall cap anglas 26 and
upper portions of wall panels. Flexible roof cover 68 is
secured in ~hat position by means of a rope 70 secured through
appropriate grommet6 in cover 68 and through eye bolts 24 on
upper tension bars 18 on the outside surfaces of panels lZ.
This roof cover is made of a suitable polymer fabric.
Inside of the reservoir structure is provided an
impermeable flexible fabric liner 74 (FIGURE 8) the upper edge
of which is secured to the inside surfaces of the panels 12 or
insulation pa~els 30~ above the desired high water level of the
reservoir. For example, grommets may be provided on the upper
wall edge of liner 74 and hooks ~eg. of stainless steel) may be
secured to wall cap angles 26 to receive a rope pas6ed through
the grommets, with its ends tied, and thereby hold the liner in
place about the inner walls of the reservoir. Alternatively,
the hooks may engage the grommets directly. This liner
- 13 -
` ~L207~
provides an impermeable barrier on the area circumscribed by
the panels. In the center of the liner 74, a hole 76 (FIGURE
7) is provided, this hole to be seated over the apertures
leading to inlet pipe 34 and outlet pipe 36 and overflow pipe
40. Liner 74 is sealed against leakage in the vicinity of hole
76 by means of a sealing ring 78 (eg. of stainless steel) of a
size to circumscribe or cover the edge of hole 76. Sealing
ring 78 is bolted to column base plate 32 to secure flexible
liner 74 about hole 76 to the base plate and thereby prevent
leakage of liquid through that hole.
As required, guide cables 84 (FIGURE 8) may be
provided, preferably above ~he high water level of the
reservoir, between the column and the wall panels to hold the
column in a vertical position during arection and to reinforce
it as a column under heavy snow loads.
Where the reservoir is to be used for holding drinking
water, bolt head~ exposed to the interior of the reservoir, for
example on sealing ring 78, may be covered with plastic.
ERECTION_PROCEDURE
(A) Ground Preparat on
A site of appropriate surface area to receive the
reservoir structure is first cleared and levelled. A trench to
receive inlet pipe 34, outlet pipe 36 and overflow pipe 40
- 14 -
~2(3~
(FIGURE 2) is made at an appropriate position, of àn appro-
priate width and to an appropriate depth. The structure may be
located on compacted earth. A level base area is important and
a surveyor ' 6 level is recommended to ensure that the compacted
area does not vary by more than say one-quarter inch in eleva-
tion. For a 5~,000 Imperial gallon capacit~ reservoir, a com-
pacted circumferential area about ~wo feet in width with an
outside diameter of forty-two feet i6 appropriate.
For a more permanent application and/or w~ere soild
conditions dictate, the reservoir walls may be erected on a
prepared concrete base curb. In this case, be~ore finalizing
the position of the concrete forms, the column base plate 32
should be located so that a tape measure can be stretched from
the column center to the curb forms. The top surface of the
con- crete should be screeded to provide a surface varying not
more than say plus or minus one-quarter inch across and around
the circumference. The inside edge of the top of the concrete
should be bevelled with a trowel before the initial set so as
not to present a sharp edge to the flexible liner 74.
~ three to four inch drop in elevation from the inside
of the wall at the base to plate 32 is desirable.
tB) Placinq of the Center C lumn Base Plate
Column base plate 32 may be laid on top of two timbers
(such as two tiers or two six inch by six inch posts) about
- 15 -
~ ~L%(~ '7~
seven or eight feet long. Care should be taken to maintain the
base plate level. The service pipes, inlet pipe 34, outlet
pipe 36 and overflow pipe 40 may be connected a~ this time to
base plate 32.
(C) Placinq Of The ~all Base Plates
Using, for example, a tape measure and measuring out
from the proposed center of the column on base plate 32, the
wall base plates 2 are laid down. The plates are joined by
means of connectors 8. The intended size of the reservoir
dictates the number of base plates 32 to be used. The base
plates, when in position, should form a completed circle. If a
completed circle is not formed, then the plates should be
shifted on the surface until such circle can be comple~ed.
Anchor bolts or anchor rods as required should be installed at
this time through holes lO.
(D) Erection of Wall Panels
Wall panels 12 should be brought to the site and laid
out like spoke6 of a wheel (FIGURE 2). From this position, two
men can elevate each panel and engage the pins 16 on the hinge
bar 14 at its base into hook brackets 6 on corresponding plate
2. The first panel can be held in place by two workmen or ~ied
in position for example by ropes. The second panel can then be
lZ(~7~7~)
. .~
erected and tension bar connectors 22 between adjacent upper
~ension bars 18 and 20 secured in placed. Care should be taken
that the vertical groove at the edge of each of the panels fits
into the edge tongue on each adjacent panel. The last panel i8
preferably left out to allow passage in and out of the reser-
voir during construction. In this regard, the top wall cap
angle 26 of that final panel can be removed and connected in
position at the top to complete the upper circle of ~all angles
and stabilize the top of the panels. The wall cap angle
connectors 28 are connected at this time.
It should be noted that some outward give is provided
in the construction of wall panels at their bases and at the
ten6ion bar 18 and 20 surrounding the panels 12. This permits
any existing slack in the tension bars to be taken up due to
pressure, when the reservoir is filled with liguid.
lE) In6tallation of the Center_Column
The column base 6pool 44 is bolted to the overflow
hole of base plate 32. The hinge bracket 58, secured to the
spool, is preferably oriented toward6 the panel gap left in the
erected wall.
The lower sectiQn 48 of column 42 and upper section 50
are preferably prejoined with appropriate threaded rods or
studs 56. The~e connected sections are joined, while in the
horizontal position, to base spool 44 by their hinge brackets
- 17 -
:~0'~9'7~)
58 by fitting an appropriate hinge bolt through these brackets
~see phan~om in FIGU~E 4). The top column cap 66 is then
attached to the top of column 42 and a "Chicago" boom device 9O
(FIGU~E 4) is releasably secured through a hole in the cap to
the ~op of the column 42. The boom device 9O con~ains a pulley
92 through which a rope 94 is threaded. The column is then
elevated by pivoting it from horizontal to vertical position
about hinge brackets (58), by the use of a powered or hand
operated winch. Side guy ropes are attached to the column to
keep it from falling sideways during this elevation procedure.
When the column is in vertical posi~ion, it is secured to base
spool 44 with appropriate bolts through confronting flanges.
Of cour6e, although not shown, gaskets are used between the
flanges of the base spool 44 and lower section 48 and in other
connection6 of elements of the structure as required.
At this point, i~ is preferable that guide cables 84
be attached between the column 42 and wall cap angles 26. Four
such guide cables, at about 90 angles to each other, have
been found to be adequate. These guide cables 84 are tightened
as required by adjusting the turn buckles 98 on guide cables 84
(FIGURE 8). The lower section 48 is thus brought into proper
vertical position using a carpenter's level. The upper section
50 of column 52 can be brought into vertical alignment with
lower section 48 at this point by appropriate adjustment of the
bolts on threaded rods 56 and the use of the carpenter's level.
- 18 -
~Z(~'79'7~
. .
(F) Installat on of Roof Trusses
Trusses 62 are brought into the reservoir area through
the panel opening one at a time. They are elevated with the
lower end of the truss placed on a wall cap angle 26. A
workman climbs column 42, a snap hook is tied securely to one
end of rope 94 and the snap hook is fastened to the upper end
of the truss 62. Workmen on the ground can ~hen pull the upper
end of the truss up to its position supported on truss plate
lOO at the top of column 42. That end is secured in place and
the other end is elevated and secured radially in place on a
wall cap angle 26, supported by a wall panel 12. Additional
trusses are brought in and placed in position in a similar
fashion. The first four trusses are placed at 9O angles to
each other. The threaded Lods at ~he overflow point on the
column are then adjusted to provide the required elevation.
The remaining trusses can then be installed. Truss braces 64
may be installed as required at this time.
(G) Installation_of R servoir Fabric Liner
Prior to installation of flexible liner 74, insula~ion
panels 30 are put in place on the inside surfaces of panels
12. To install the liner, the lower bolts securing the upper
flange of lower section 48 on threaded rods 56 are slackened
off and the lower section 48 is elevated from the top of base
-- 19 --
:~ ~075~'71)
.
spool 44 by tightening the lower nuts. This is done after
remvoing the upper bolts on the base spool. The base spool can
now be remo~ed after removal of the bolts on its lower flange,
connecting it to the base plate. Section 48 and 50 are now
supported by trusses 62. Final le~elling of the area within
the walls is now carried out. The reservoir liner 74 is then
brought in and unfolded. Grommets (not shown) may be provided
around the lower edge of the liner to as~ist in manoeuvring it
into position. Short ropes can be placed in these grommets to
drag it into position. The large hole 76 in the centre of
liner 74 is positioned with its edge on base plate 32. A
special neoprene gasket (not shown) may be provided to assist
the seal at this location. The base spool 44 is now returned
to its postion and bolted to the base plate. The nuts on ~he
threaded rods 56 about the lower flange 54 are adjusted to
close the gap to the base spool and to ensure a downward
pressure ensuring a slight upwards thrust of the column to its
truss plate and the trusses.
The final wall panel 12 is now to be secured in
position before the raising of the liner up the weall to its
final position.
A length of plastic rope is threaded through the grom-
mets (not shown) on the upper wall edge of the flexible liner
74 and the rope ends are tied together. Stainless steel hooks
are then secured in position in appropria~te holes on the inside
edges of wall cap angles 26. The liner is pulled up the wall
- 20 -
~ ~Z~'~9'~
and the rope is hoo~ed onto the stainless steel hooks, OL ~he
hooks may be engaged into the grommets directly. The edge of
liner 74 should sit above the elevation of the highest level of
liquid to be held in the reservoir structure, to ensure that
the liquid does not overflow down between the liner and the
insuation.
(H~ Installatio,n of the Reservoir Cover
The Chicago boom device 90 is removed and a pipe
fairlead 104 (FIGURE 6) installed. A rope is fed through pipe
fairlead 104 and down to the ground on opposite sides of the
reservoir structure. A special roller 106 to assist in raising
flexible roof cover 68 is installed at the top of an
appropLiate section of wall of the reservoir. Cover 68 is
folded pie fashion so that the centre of the cover is at the
point of the rope pull attachment. Using a clamp 105 secured
to the rope, or by securing with the end of the rope itself.
the fold- ed roof cover 68 may be dragged up over roller 106,
up the slope of trusses 62, to the apex of the reservoir. The
rope is removed and pipe fairlead 104 removed. The roof cover
68 i6 then unfolded and ~ half pulled over the top to its final
position. The r~of cover should be adjusted so that it extends
evenly down over the outer surface of the wall panels 12. ~n
appropriate nylon 70 is provided for lacing the cover to
eyebolt~ 24 on the upper tension bar 18. Rope 70 is preferably
~..
3797(;)
in parts 80 that a portion may be unlaced for access into the
reservoir or for the addition of chemicals etc., without
slackening the remainder of the ropes.
It will be understood that the reservoir structure
according to the present invention may be quickly erected and
dismantled in a manner requiring very little expertise and very
~ le manpower. The elements making up the structure are of
regular shape, and of relatively small size, permitting their
containerization or palletization and ready transportation.
The flexible liner is installed, according to the
method of the eresent in~ention, as one of the last steps of
the process of construction of the container. This means that,
where the reservoir is intended to be used for a supply of
drinking water, workers erecting the structure have minimum
need to walk on the liner, thereby assisting in maintaining
cleanline6s of the inneL surface of the liner as well as
avoiding damage to it.
Moreover, it should be noted that there are very few
bolts or sharp edges exposed to the flexible liner 74 when it
is pulled into position through the column gap in the reservoir
structure - flush inner &urfaces are provided by the wall
panels and insulation, and by the bottom prepared surace
within the walls. Another advantage of the present structure
is that the central column 42 i6 seated not on the liner, but
instead on column base plate 32. This reduces wear on the
liner and improves the structural soundness of the system.
~ lZ(~'7~'7~
Thus it is apparent that there has been provided in
accordance with the present invention a demountable portable
reservoir structure that fully satisfies the objects, aims and
advantages set forth above. While the invention has been de-
scribed in conjunction with specific embodiments thereof, it isevident that many alternatives, modifications and variations
will be apparent to those skilled in the art in light of the
foregoing descrip~ion. Accordingly, it is intended to embrace
all such alternatives, modifications and variationsnas fall
within the spirit and broad scope of the appended claims.
