U.S. patent application number 13/647570 was filed with the patent office on 2013-04-11 for portable above-ground containment system and method.
This patent application is currently assigned to TrussTank, LLC. The applicant listed for this patent is TrussTank, LLC. Invention is credited to Christopher F. Bohley, Richard T. Hughes.
Application Number | 20130087558 13/647570 |
Document ID | / |
Family ID | 48041420 |
Filed Date | 2013-04-11 |
United States Patent
Application |
20130087558 |
Kind Code |
A1 |
Bohley; Christopher F. ; et
al. |
April 11, 2013 |
Portable Above-Ground Containment System and Method
Abstract
An above-ground containment system comprises a plurality of
truss assemblies, a band coupled to the truss assemblies, and a
flexible liner. The truss assemblies are disposed in an arrangement
defining a storage area. The band is coupled to the truss
assemblies and encircles the storage area, and tensionably
maintains the tress assemblies in the desired position. The liner
is coupled to the truss assemblies and includes a central portion
covering a base of the storage area.
Inventors: |
Bohley; Christopher F.;
(Clearfield, PA) ; Hughes; Richard T.;
(Clearfield, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TrussTank, LLC; |
Clearfield |
PA |
US |
|
|
Assignee: |
TrussTank, LLC
Clearfield
PA
|
Family ID: |
48041420 |
Appl. No.: |
13/647570 |
Filed: |
October 9, 2012 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
61545956 |
Oct 11, 2011 |
|
|
|
Current U.S.
Class: |
220/4.12 ;
29/897.3 |
Current CPC
Class: |
B65D 90/50 20130101;
E04H 7/06 20130101; B65D 88/528 20130101; B65D 90/205 20130101;
E04H 7/32 20130101; E04H 7/30 20130101; Y10T 29/49623 20150115 |
Class at
Publication: |
220/4.12 ;
29/897.3 |
International
Class: |
B65D 88/52 20060101
B65D088/52; B65D 90/50 20060101 B65D090/50 |
Claims
1. An above-ground containment system, comprising: a plurality of
truss assemblies, each of said truss assemblies including a first
portion and an opposite second portion, said first portions of said
truss assemblies disposed in an arrangement defining a periphery of
a storage area, and said second portions of said truss assemblies
disposed outwardly from said storage area; a band coupled to said
second portions of said truss assemblies and encircling said
storage area, said band tensionably maintaining said plurality of
tress assemblies in said arrangement; and a liner having a
peripheral portion coupled to said first portions of said truss
assemblies and a central portion covering a base of said storage
area.
2. The containment system of claim 1, wherein the storage tank
system is capable of retaining at least about 50,000 thousand
gallons of material in said storage area.
3. The containment system of claim 2, wherein the storage tank
system is capable of retaining at least about 2 million gallons of
material is said storage area.
4. The containment system of claim 1, wherein said band is high
strength wire strand.
5. The containment system of claim 1, wherein said band is a first
band, further comprising at least a second band coupled to said
outer portions and encircling said storage area.
6. The containment system of claim 1, wherein each of said first
portions comprises a planar panel portion angled outwardly and away
from said base of said storage area.
7. The containment system of claim 6, wherein said second portions
comprise a plurality of support beams disposed substantially
perpendicular to said base of said storage area.
8. The containment system of claim 1, wherein each of said second
portions comprises a load transfer plate, said load transfer plates
collectively forming a load transfer ring encircling said storage
area when said truss assemblies are disposed in said arrangement,
and said band coupled to said load transfer ring.
9. The containment system of claim 1, wherein each of said truss
assemblies includes a plurality of braces extending between and
interconnecting said first portion and said second portion.
10. The containment system of claim 1, wherein said storage area
has one of a substantially circular or a substantially elliptical
configuration in plan view.
11. The containment system of claim 1, wherein said truss
assemblies are formed substantially from a material selected from
the group consisting of wood, wood composite, plastic, and
metal.
12. The containment system of claim 1, further comprising a leakage
monitoring system comprising: a perforated pipe extending across a
portion of said base, said liner covering said perforated pipe; and
a monitoring pipe including a first end portion coupled to said
perforated pipe and a second end portion disposed out of said
storage area.
13. The containment system of claim 12, wherein said monitoring
pipe is coupled to said first portion of one of said truss
assemblies.
14. A truss assembly for a storage structure, said truss assembly
comprising: a planar panel portion disposed in an arrangement with
a plurality of additional truss assemblies to define a periphery of
a storage area; a truss portion including a first portion coupled
to said planar panel portion and an opposite second portion; and a
load transfer plate coupled to said second portion of said truss
portion and including a retaining member configured to secure a
tensioning band thereto, wherein said load transfer plates of said
truss assemblies disposed in said arrangement form a load transfer
ring configured to receive said tensioning band.
15. The truss assembly of claim 14, further comprising a puncture
resistant liner coupled to said planar panel portion.
16. The truss assembly of claim 15, further comprising a backing
layer intermediate said liner and said planar panel portion.
17. The truss assembly of claim 15, wherein said liner is formed
from a linear low-density polyethylene.
18. The truss assembly of claim 14, wherein said truss portion is
formed substantially from a material selected from the group
consisting of wood, wood composite, plastic, and metal.
19. The truss assembly of claim 14, wherein said load transfer
plate is formed from a material selected from the group consisting
of wood, wood composite, plastic, and metal.
20. A method of erecting an above-ground storage structure,
comprising the steps of: providing a plurality of truss assemblies,
each of said truss assemblies including a first portion including a
planar panel and an opposite second portion including a load
transfer plate; positioning the plurality of truss assemblies so
that the planer panels of the first portions of the truss
assemblies define a periphery of a storage area, and the load
transfer plates form a load transfer ring; coupling a band to the
load transfer ring so that the band is surrounding the truss
assemblies and the storage area; applying tension to the band so
that the planar panels of the truss assemblies are aligned along
the periphery of the storage area; and coupling a peripheral
portion of a liner to the planar panels of the truss assemblies so
that the liner is covering a base of the storage area.
21. The method of claim 21, wherein the plurality of truss
assemblies are positioned in one of a substantially circular or a
substantially elliptical configuration in plan view.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on U.S. Patent Application Ser.
No. 61/545,956, filed Oct. 11, 2011, entitled "Temporary Above
Ground Tank System Fabricated of Trusses and High Strength Steel
Strand," which application is incorporated herein by reference in
its entirety and to which priority is claimed.
FIELD OF THE INVENTION
[0002] The present invention relates to an above-ground containment
structure, and in particular a portable storage tank suitable for
containing fluid or other solid or granular material.
BACKGROUND OF THE INVENTION
[0003] Various industries and processes require a portable or
movable storage tank or basin for storing product, both fluid and
granular, on a temporary basis and in a cost effective manner.
Several storage systems are known in the art. One conventional
system includes a below-ground basin lined with a polymer material
for retaining fluid. However, such basins or ponds are relatively
expensive to form, requiring extensive excavation, and are prone to
leakage and thus ground water and soil contamination. Other fluid
retaining systems provide for a relatively large steel tank, which
may be positioned below or above-ground. Such tanks are unwieldy
and bulky, prone to rusting, and have not proven viable for
relatively large volumes of fluid.
[0004] Another fluid retaining system includes an above-ground
fluid retaining tank including a network of steel or concrete
supports or walls. While such above-ground systems do not require
extensive below-ground excavation, they are bulky and extremely
heavy given the weight of the steel or concrete supports must
counteract the outward forces generated by the weight of the fluid
being retained. As such, the cost of transporting and installing
the materials needed for such systems is relatively high given the
total weight of the steel and concrete supports and walls.
Likewise, the cost of dismantling and removing the steel and
concrete supports and walls is likewise excessive. Thus, such
conventional retaining systems are not truly portable, given the
cost to assemble, and dissemble and remove such systems is
excessive.
[0005] Such conventional fluid retaining systems are nevertheless
needed and therefore used in a variety of industries and
applications. One such industry that requires a readily available
source of fluid is the natural gas and mining industry. Shale gas
production has grown rapidly in the United States and elsewhere due
in part to improved drilling and extraction methods. One extraction
method is hydraulic fracturing, which involves the propagation of
fractures in a rock layer caused by the presence of a pressurized
fluid. Hydraulic fracturing is used to increase the rate at which
fluids, such as natural gas or oil, can be extracted from rock
layers or reservoirs.
[0006] Hydraulic fractures form naturally, such as in veins or
dikes, and are one means by which gas and petroleum from source
rock may migrate to reservoir rock formations. This fracturing
process may be accelerated by injecting highly pressurized fracking
fluid into a wellbore drilled into reservoir rock formations. The
energy from the injection of the fracking fluid creates new
channels in the rock, thereby increasing the extraction rates and
ultimate recovery of the natural gas or other fuels. Thus, the
created fractures provide a conductive path connecting a larger
area of the reservoir to the well, thereby increasing the area from
which natural gas or oil may be recovered from the targeted
formation.
[0007] A hydraulic fracture is formed by pumping the fracking fluid
into the wellbore at a rate sufficient to increase pressure
downhole to exceed that of the fracture gradient of the rock. The
rock is thereby cracked and the fracture fluid forced farther into
the rock, thereby extending the crack. In order to prevent the
formed fractures from closing when the injection process is
stopped, a solid proppant (e.g., grains of sand or ceramic) is
typically added to the fluid. The fracture is thus permeable enough
to allow the flow of formation fluids (e.g, natural gas or oil) to
the well.
[0008] In addition to proppants, the fracking fluid may also
contain chemical additives, gels, foams, and compressed gases.
However, water is the largest component of fracking fluid,
typically accounting for approximately 98% of fracking fluids.
Low-volume hydraulic fracturing used to stimulate high-permeability
reservoirs may consume typically 20,000 to 80,000 gallons of fluid
per well, while high-volume hydraulic fracturing, such as used in
shale gas wells, may use two to three million gallons or more of
fluid per well. Thus, fracturing operations require a relatively
large and readily available source of water, such as from a fluid
retaining basin or conventional tank.
[0009] The gas, oil or other substance is extracted from the
wellbore along with wastewater, which may include the water and/or
other components of the fracking fluid along with other naturally
occurring elements such as salt, metals and other elements.
Retaining basins or tanks are therefore also needed for containing
the wastewater until it can be further processed or hauled away for
treatment and/or disposal.
[0010] Conventional storage tanks and systems fail to provide an
adequate solution for temporarily retaining large volumes of fluid,
such as needed in the natural gas and oil industry. Such
conventional tanks and systems are not easily assembled, dissembled
or moved, and thus are not cost effective.
[0011] Accordingly, there is a need for a storage system that is
relatively easy to assemble and disassemble, and which provides for
the storage of fluids and granular materials on a temporary basis
and in a cost effective and efficient manner. In particular, there
is a need for a portable, above-ground retaining structure that can
accommodate relatively large volumes of material, including fluid
or granular materials, such as one million or more gallons of such
material. The present invention solves some or all of the
above-noted deficiencies of conventional retaining systems.
SUMMARY OF THE INVENTION
[0012] The present invention is directed to an above ground,
portable storage tank system or containment structure that may be
be utilized for various applications for containing or retaining
fluids and granular materials.
[0013] An above-ground containment system according to an
embodiment of the present invention includes a plurality of truss
assemblies, one or more retaining bands, and a liner. Each the
truss assemblies includes a first portion and an opposite second
portion. The first portions of the truss assemblies are disposed in
an arrangement defining a periphery of a storage area. Preferably,
the storage area has a substantially circular or elliptical
configuration in plan view. The second portions of the truss
assemblies are disposed outwardly from the storage area. The
band(s) is coupled to the second portions of the truss assemblies
and encircles the storage area. The band tensionably maintains the
plurality of tress assemblies in the arrangement. The liner has a
peripheral portion coupled to the first portions of the truss
assemblies and a central portion covering a base of the storage
area.
[0014] In one embodiment, the containment system is capable of
retaining at least about 50,000 thousand gallons of material in the
storage area. More preferably, the system is capable of retaining
at least about 2 million gallons of material is the storage area.
In one implementation, the system is capable of retaining at least
about 3 million gallons of material in the storage area.
[0015] In one embodiment, the band is high strength wire strand.
The containment system may include a single retaining band, or
alternatively two or more retaining bands that are coupled to the
outer portions and encircle the storage area.
[0016] In one embodiment, the first portions of the truss
assemblies include a planar panel portion angled outwardly and away
from the base of the storage area. The second portions may include
a plurality of support beams disposed substantially perpendicular
to the base of the storage area.
[0017] In one embodiment, each of the second portions of the truss
assemblies comprises a load transfer plate. The load transfer
plates of the arranged truss assemblies collectively form a load
transfer ring encircling the storage area. The band(s) is coupled
to the load transfer ring.
[0018] In one embodiment the containment system includes a leakage
monitoring system. In one implementation, the leakage monitoring
system includes a perforated pipe extending across a portion of the
base of the storage area, and a monitoring pipe. The liner covers
the perforated pipe and monitoring pipe. The monitoring pipe
includes a lower end coupled to the perforated pipe and an upper
end disposed out of the storage area and accessible by a user.
[0019] The present invention is also directed to a truss assembly
for a storage structure. The truss assembly includes a planar panel
portion disposed in an arrangement with a plurality of additional
truss assemblies to define a periphery of a storage area. A truss
portion includes a first portion coupled to the planar panel
portion and an opposite second portion. A load transfer plate is
coupled to the second portion of the truss portion, and includes a
retaining member configured to secure a tensioning band thereto.
The load transfer plates of the truss assemblies disposed in the
arrangement form a load transfer ring configured to receive the
tensioning band.
[0020] In one embodiment, the truss assembly includes a puncture
resistant liner coupled to the planar panel portion. The liner may
be formed from a linear low-density polyethylene. In some
embodiments, the truss assembly additionally includes a backing
layer intermediate the liner and the planar panel portion. The
truss assembly components may be formed from various materials,
including but not limited to wood, wood composite, plastic, or
metal.
[0021] The present invention also relates to a method of erecting
an above-ground storage structure. The method includes the steps
of: providing a plurality of truss assemblies, each of the truss
assemblies including a first portion including a planar panel and
an opposite second portion including a load transfer plate;
positioning the plurality of truss assemblies so that the planer
panels of the first portions of the truss assemblies define a
periphery of a storage area, and the load transfer plates form a
load transfer ring; coupling a band to the load transfer ring so
that the band is surrounding the truss assemblies and the storage
area; applying tension to the band so that the planar panels of the
truss assemblies are aligned along the periphery of the storage
area; and coupling a peripheral portion of a liner to the planar
panels of the truss assemblies so that the liner is covering a base
of the storage area. In preferred embodiments, the plurality of
truss assemblies is positioned in one of a substantially circular
or a substantially elliptical configuration in plan view.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 illustrates a perspective view of a containment
structure according to an embodiment of the present invention.
[0023] FIG. 2 illustrates an exploded perspective view of the
containment structure showing an arranged plurality of truss
assemblies, retaining band and flexible liner.
[0024] FIG. 3 illustrates a side elevational view of a truss
assembly according to an embodiment of the present invention.
[0025] FIG. 4 illustrates a side elevational view of a truss
assembly and liner according to an embodiment of the present
invention.
[0026] FIG. 5 illustrates a front perspective view of a truss
assembly according to an embodiment of the present invention,
showing a cut-away view of layers of a liner system and panel of
the truss assembly.
[0027] FIG. 6 illustrates a side elevational view of a truss
assembly, liner and backing layer according to an embodiment of the
present invention.
[0028] FIG. 7 illustrates a rear perspective view of a truss
assembly and partial views of adjacent aligned truss assemblies
disposed in an arrangement according to an embodiment of the
present invention.
[0029] FIG. 8 illustrates a top plan view of truss assemblies
disposed in a circular arrangement, and showing a portion of a
leakage monitoring system according to an embodiment of the present
invention.
[0030] FIG. 9 illustrates a sectional view of a portion of the
leakage monitoring system according to an embodiment of the present
invention.
[0031] FIG. 10 illustrates a side elevational view of a truss
assembly and a portion of the leakage monitoring system according
to an embodiment of the present invention.
[0032] FIG. 11 illustrates a sectional view of another portion of
the truss assembly and leakage monitoring system according to an
embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0033] The present invention is directed to an above ground storage
tank system or containment structure that may be be utilized in
various industries and applications for the containment of
materials, including both fluids and granular materials. The
disclosed storage system is relatively portable or movable, and may
be quickly and easily erected at a particular site, with little to
no site preparation required. Once the need for storage at the
particular site is met, the disclosed system may be easily
disassembled and/or relocated to another site. The environmental
impact at the site is therefore minimal. The disclosed system
includes a plurality of truss assemblies or segments, which are
coupled together and maintained in position via a retaining band or
wire. Compared to conventional storage tanks and systems, and in
particular non-movable or bulky conventional concrete storage
systems, the system of the present invention provides the user with
the flexibility to assemble and/or disassemble a storage structure
quickly and easily, and for a fraction of the cost compared to
other conventional systems.
[0034] Referring to FIGS. 1 and 2, an above-ground containment
system 10 according to an embodiment of the present invention is
illustrated. The containment system 10 includes a plurality of
discrete truss assemblies 12 that are arranged in a selected
orientation or arrangement A1 to define a periphery 14 of a storage
area 16. As shown in FIG. 3, one or more bands 18 are coupled to
the truss assemblies and surround or encircle the storage area 16.
It should be understood that the illustration of five bands 18 in
FIG. 3 is for purposes of explanation only, and systems including
fewer or more than five bands 18 may be provided depending on the
particular requirements of the systems (described in further detail
below).
[0035] Referring again to FIGS. 1 and 2, a puncture resistant liner
20 overlies the storage area 16 and is coupled to the truss
assemblies 12. The containment system 10 is preferably capable of
retaining at least about 50,000 gallons of fluid or other granular,
powder or other material, more preferably at least about 100,000
gallons of fluid or other material, more preferably at least about
1 million gallons of fluid or material, more preferably at least
about 2 million gallons of fluid or material, and in some
implementations at least about 3 million gallons or more of fluid
or other material.
[0036] Referring again to FIG. 3, each of the truss assemblies 12
includes a first portion 22 and an opposite second portion 24. The
first portion 22 includes a planar portion or planar panel 26
having an outer face 28, whereby the plurality of outer faces 28 of
the planar panels 26 define the periphery 14 of the storage area 16
when the truss assemblies 12 are selectively arranged (e.g., such
as in arrangement A1). The second portion 24 of the truss assembly
12 is disposed outwardly and spaced from the storage area 16. In
one embodiment, a secondary planar panel or top panel 30 is coupled
to and extends between an upper end 32 of the first portion 22 and
an upper end 34 of the second portion 24.
[0037] In a preferred embodiment, components of the truss
assemblies 12 are formed from wood or engineered wood products. In
other embodiments, components of the truss assemblies 12 may be
constructed from other materials such as a polymer and polymer
composites (e.g., a reinforced polymer composite), light gauge
steel, cold formed steel, hot rolled steel, or another material
having sufficient structural properties. Preferably, the truss
assemblies 12 are relatively light weight and/or easily assembled
or disassembled to facilitate ease of transport and positioning
thereof. In one embodiment, the planar panels 26 are constructed of
engineered wood sheeting; alternatively, the planar panels 26 are
constructed of light gauge steel sheeting, or a polymer or polymer
composite material.
[0038] The band(s) 18 is coupled to the second portions 24 of the
truss assemblies 12, and encircles the arranged truss assemblies 12
and thus the storage area 16. The band(s) 18 tensionably maintains
the truss assemblies 12 in the selected arrangement (e.g., such as
arrangement A1). In one embodiment, each band 18 is a high strength
steel tension band, such as utilized for pre-stressing and post
tensioning precast concrete. In a preferred embodiment, the band is
high strength 5 wire or 7 wire strand. For example, the band 18 may
exhibit a tensile strength of 270,000 pounds per square inch or
more.
[0039] As noted above, the containment system 10 may include more
than one band 18, depending on the support required to resist the
outwardly directed forces (shown by arrow F1 in FIG. 3) generated
by the fluid or other material being stored within the storage area
16. For example, the system 10 may include five bands 18 coupled to
the second portions 24 of the truss assemblies 12 and surrounding
the storage area 16, as illustrated in FIG. 3. Alternatively and/or
in addition, the strength of the band(s) 18 may be increased or
decreased depending on the support required to resist the outwardly
directed forces F1.
[0040] Referring to FIGS. 1 and 4, an outer portion 36 of the liner
20 is coupled to the outer faces 28 of the planar panels 26 of the
truss assemblies 12. A central portion 38 of the liner 20 covers
and defines a base 40 of the storage area 16. In one embodiment, a
peripheral portion 42 of the liner 20 extends outwardly from the
storage area 16, over and across the top panels 30, and against or
adjacent the second portions 24 of the truss assemblies 12 as well
as one or more of the bands 18, as shown in FIG. 4. The peripheral
portion 42 may, but need not, be secured or coupled to the second
portions 24, either directly or indirectly, thereby further
maintaining the liner 20 in a desired position relative to the
truss assemblies 12. In one embodiment, the liner 20 is formed from
a flexible material, such as for example a linear low-density
polyethylene (LLDPE).
[0041] Referring to FIGS. 5 and 6, according to one embodiment a
backing layer 44 is provided intermediate the liner 20 and the
outer faces 28 of the planar panels 26. The backing layer 44 may
extend against or across the top panels 30, and optionally and
additionally downwardly along or adjacent the second portions 24 of
the truss assemblies 12. Thus, the backing layer 44 aids in
maintaining the arrangement of and coupling together the truss
assemblies 12 in their desired arrangement. Optionally and
additionally, the backing layer 44 may extend outwardly from the
outer faces 28 of the planar panels 26 and into the base 40 of the
storage area 16, as shown in FIG. 6. One or more additional backing
layers may be provided, as necessary for the particular site
requirements. For example, a secondary backing layer 45 may be
provided, on which the truss assemblies 12 rest, as shown in FIG.
6.
[0042] In one implementation, the backing layer 44 is formed from a
flexible, permeable, non-woven material, such as a geotextile
fabric. The geotextile backing material may be constructed of woven
or non-woven material of various thicknesses, such as typically
used in the earth moving and construction industries. The backing
layer 44 may alternatively be constructed from another suitable
material that provides adequate cushioning, adequate puncture
protection, and adequate permeability and gas venting properties to
protect the liner 20.
[0043] The liner system utilized may be constructed of a single
layer or multiple layers of a scrim reinforced LLDPE or other
similar material, such as typically used for landfill liners, pond
liners, in-ground earthen impoundments, or the like. However, the
liner system may alternatively be constructed of another suitable
material capable of retaining fluid or granular material, providing
adequate resistance to chemical degradation from the material being
stored, and providing adequate puncture and ultra-violet
resistance. The actual number of liner layers utilized is dependent
on the material being stored, as well as on any storage regulations
on such stored material.
[0044] With continued reference to FIG. 6, the planar panels 26 of
the truss assemblies 12 are preferably angled outwardly and away
from the base 40 of the storage area 16. Referring to FIGS. 6 and
7, the second portions 24 include support beams 46 that are
preferably disposed substantially perpendicular to the base 40 of
the storage area 16. Thus, the support beams 46 are also preferably
disposed substantially perpendicular to the ground or support
surface on which the containment system 10 rests. A plurality of
braces 48 extend between and interconnect the first portion 22 and
the support beams 46 of the second portion 24. A bottom brace 49
may also be provided adjacent or coupled to a lower end 33 of the
first portion 22 of each of the truss assemblies 12. The bottom
brace 49 provides additional support to the individual truss
assemblies 12, and may be constructed of wood, light gauge steel,
engineered wood products, composite materials, a polymer material,
or another material having sufficient structural properties.
[0045] It should be understood that the specific dimensions and
number of support beams 46, planar panels 26 and other components
of the first portion 22, and/or braces 48 may vary depending on the
structural capabilities necessary and required for a particular
application. Thus, the specific configuration of the truss
assemblies 12 may vary depending on the particular application and
in order to provide adequate structural loading for the particular
application.
[0046] One of more load transfer plates 50 are coupled to and
extend between the support beams 46 of the second portion 24 of
each truss assembly 12. The load transfer plate(s) 50 is preferably
formed from wood or engineering wood products, but may
alternatively be formed from another material such as plastic,
light gauge steel, composite materials, or some other material
having adequate structural properties. Preferably, the load
transfer plate 50 is formed from a relatively light weight material
which permits a sufficient amount of flexure or curvature to
account for the curved configuration of the outer portion of the
truss assembly, as best shown in FIGS. 2, 5 and 7.
[0047] In one embodiment, the load transfer plate(s) 50 is
connected to and extends across the support beams 46. Preferably,
each truss assembly 12 includes at least an upper load transfer
plate 50 proximate to a top portion 52 of the truss assembly 12,
and a lower load transfer plate 50 proximate to a bottom portion 54
of the truss assembly 12. One or more intermediate load transfer
plates 50 may be provided intermediate the upper and lower load
transfer plates 50, as shown in FIG. 7. Preferably, the load
transfer plates 50 extend substantially parallel to each other, and
substantially perpendicular to the length and longitudinal axis of
the support beams 46.
[0048] As best shown in FIG. 2, the ends of each load transfer
plate 50 associated with one truss assembly 12 align with
correspondingly positioned ends of load transfer plates 50 on
another adjacent truss assembly 12 when the truss assemblies 12 are
disposed in the selected arrangement A1 forming the storage area
16. In this way, the load transfer plates 50 of the arranged truss
assemblies 12 form one or more load transfer rings 56 surrounding
the storage area. Opposite ends of the wire or cable material
forming the band(s) 18 are coupled together using clamps, brackets
or other such devices known to those of skill in the art. The
band(s) 18 is coupled to one of the load transfer rings 56, such as
via brackets, clamps or other such retaining members. Preferably,
one or more bands 18 are coupled directly to and in engagement with
the load transfer ring 56, as shown in FIGS. 3, 4 and 6. Additional
bands 18 may be coupled to other load transfer rings 56 provided on
the truss assemblies. For example, two or more bands 18 may be
coupled to one of the load transfer rings 56. Preferably, the load
transfer rings 56, and thus bands 18, are vertically spaced along
the height of the truss assemblies 12 in order to effectively
resist the outwardly directed forces F1 (shown in FIG. 3) from the
fluid or material being contained in the storage area 16.
[0049] The various loops of the bands 18 provide the necessary
support required to resist the outwardly directed forces F1 or hoop
stress generated by the fluid or granular material being contained
in the storage area 16. Once the bands 18 are installed and an
initial stress is imparted to each of the bands 18, the backing
layer 44 may be draped over the top panel 30 and outer faces 28 of
the planar panels 26 of the truss assemblies 12. The liner 20 is
then placed within the storage area 16, and unrolled or positioned
therein so that the entire base 40 of the storage area 16 is
covered by the liner 20. The outer portion 36 of the liner 20 is
coupled to and/or overlaps the backing layer 44, and thus is
coupled to and/or overlaps the planar panels 26 and top panels 30
of the truss assemblies 12, such as shown in FIGS. 1 and 6.
Depending on the required diameter of the storage area 16, the
liner 20 may be formed from a single width of material (having one
or more layers) or alternatively multiple pieces of material may be
bonded or coupled together, such as by heat welding multiple pieces
together, to achieve the required width.
[0050] In preferred embodiments, the storage area 16 has either a
circular or elliptical configuration, as shown in FIG. 1. A
circular or elliptical arrangement of truss assemblies 12
distributes the outwardly directed forces F1 generated by the fluid
or material being stored in the storage area 16 more evenly to the
encircling or surrounding band(s) 18. However, the storage area 16
may be of various shapes and sizes to meet the requirements of the
particular application. In addition, the specific size and
configuration of the truss assemblies 12 may vary depending on the
requirements of the particular application. For example, the size
and configuration of the containment system 10 may be determined
based on the required storage volume, the material type (liquid or
granular) to be stored, and the site requirements (e.g., regulatory
requirements, topographical features, geological considerations,
drainage considerations, waterways and ground water features of the
site). The location, configuration and size of the system 10 may
then be designed with consideration of such site requirements.
[0051] Preferably, the truss assemblies 12 are prefabricated off
site, and then transported to the site as assembled and discrete
segments to minimize on site construction time. The truss
assemblies 12 may be placed directly on the ground or another
suitable surface, which will ultimately serve as the base of the
storage area 16. Preferably, the truss assemblies 12 are positioned
on a relatively flat area. Alternatively or additionally, the
ground G may be leveled or smoothed, with any larger rocks, brush
or vegetation removed, in preparation for locating the containment
system 10. A sand bedding S or other similar material suitable for
quickly leveling the ground G may alternatively or additionally be
utilized, as shown in FIG. 4.
[0052] It should be understood that the sand bedding S or other
level material, and/or other ground preparations required prior to
assembly and installation of the system 10, are minimal compared to
site preparation requirements for conventional storage systems. For
example, the sand bedding S for system 10 may have a depth of only
several inches, depending on the conditions of the surface of the
ground G. By comparison, a conventional above-ground storage tank
typically requires a sub-base including structural fill (e.g.,
stone) having a depth of 8 feet or more in order to support the
high forces and weight of the resulting tank. Conventional
above-ground tanks, when filled with fluid, transfer virtually all
of the weight from the material being stored downwardly or
vertically relative to the ground. For example, a conventional
above-ground tank may easily transfer a downward or vertical force
on the ground exceeding 6000 pounds per square foot. By contrast,
the disclosed system 10 transfers a substantial portion of the
force from the weight of the stored material outwardly or
horizontally, transferring the horizontal forces F1 outwardly and
to the load transfer rings 56 and bands 18, as described above.
Thus, the system 10 results in a substantial decrease in the
downward forces (e.g., system 10 may transfer a vertical force of
only 600 pounds per square foot, or 1/10 the vertical forces
exhibited by a conventional tank of comparable size and storage
holding capabilities).
[0053] When the truss assemblies 12 are properly positioned
relative to each other at the desired site location, such as in a
circular arrangement A1, the load transfer plates 50 are aligned to
form load transfer rings 56, as described above. The specific size
of the truss assemblies 12 and overall system 10 may vary depending
on the particular application. For example, the truss assemblies 12
may have a height of about 12 feet or more, with the storage area
16 having a diameter of about 200 feet or more. Larger or smaller
storage areas may be provided as desired. Thus, the height and
width of the truss assemblies 12 may vary depending on the desired
size of the storage area 16. Moreover, the angle at which the
planar panels 24 are disposed relative to the base 40 of the
storage area 16 (and thus the resulting configuration of the truss
assemblies 12) may also vary depending on the size and load
requirements for the system 10.
[0054] According to one embodiment, the containment system 10
includes a leakage monitoring well or system. In one
implementation, the monitoring system includes a section of
perforated pipe 60 extending across the base 40 of the storage area
16. Referring to FIGS. 8 and 9, the perforated pipe 60 extends
across substantially across a diameter of the storage area 16. As
shown in FIG. 9, a channel C or depression may be formed or
utilized in the ground G, and/or optionally or additionally in the
bedding S. The perforated pipe 60 is then disposed within the
channel C, so that the perforated pipe 60 is disposed beneath and
vertically lower than the liner 20. One or more secondary liners 62
or fabric layers may be provided within the channel C, so that the
perforated pipe 60 is disposed within the channel C, and between
the secondary liner 62 and liner 20. Additionally, sand or other
filler material may be placed around the perforated pipe 60, so
that the perforated pipe 60 is substantially buried or disposed
within the channel C beneath the base 40 of the storage area 16.
Any fluid or material that leaks through the liner 20 is directed
and flows toward the channel C and then into the perforated pipe
60.
[0055] The perforated pipe 60 is preferably angled downwardly
within the channel C and along its longitudinal axis, so that an
end 64 of the perforated pipe 60 is slightly lower than the
opposing end 66 thereof. In this way, any fluid that collects or
migrates into the perforated pipe 60 flows downwardly to the lower
end 64. Referring to FIGS. 10 and 11, the lower end 64 of the
perforated pipe 60 is coupled to a lower end 68 of a monitoring
pipe 70. The monitoring pipe 70 extends upwardly and out of the
storage area 16, so that an upper end 72 thereof is disposed out of
the storage area 16 and accessible to a user. Preferably, the
monitoring pipe 70 is coupled to or adjacent the planar panel 26 of
one of the truss assemblies 12, so that access to the upper end 72
of the monitoring pipe 70 is provided from or near the top panel 30
thereof.
[0056] The monitoring pipe 70 may be disposed between the backing
layer 44 and the liner 20, as best shown in FIG. 11. Additionally,
one or more secondary liners 74 or fabric layers may extend over
and cover the monitoring pipe 70, so that the monitoring pipe 70 is
disposed between the secondary liner(s) 74 and backing layer 44.
Preferably, the monitoring pipe 70 is not porous and/or does not
include any openings or perforations.
[0057] Any fluid that collects in the perforated pipe 60 is
channeled downwardly and flows toward end 64, and is then visible
through the monitoring pipe 70. Alternatively or additionally, the
user may readily lower an appropriate gauge, fluid detection
equipment, or absorbent material into the monitoring pipe 70 to the
end 64 of the perforated pipe 60. Any fluid present at the end 64
of the perforated pipe 60 is readily detected. Thus, a cost
efficient leakage monitoring system may be easily provided for the
containment system 10.
[0058] After the truss assemblies 12 are in positioned in the
predetermined arrangement (e.g., arrangement A1), the high strength
steel tension wires are positioned around the arranged truss
assemblies, with opposing ends of the wires connected to form the
bands 18. The bands 18 are coupled to the load transfer ring(s) 56,
as described above, so that the bands 18 surround the truss
assemblies 12 and the storage area 16. The bands 18 and load
transfer ring(s) 56 are distributed over the exterior or second
portions 24 of the truss assemblies 12, so that the outwardly
directed forces F1 or hoop stresses imparted on the truss
assemblies 12 by the weight of the fluid or material ultimately
disposed within the storage area 16 may be resisted. Upon coupling
the bands 18 to the load transfer rings 56, the bands 18 are
initially minimally pre-tensioned or pre-stressed in order to seat
and further align the planar panels 26 of the truss assemblies 12
in their desired arrangement. As the bands 18 are further tensioned
and tightened around the load transfer rings 56, the truss
assemblies 12 are drawn into relatively tight engagement with each
other.
[0059] Once the truss assemblies 12 are fully seated via the
pre-tensioned bands 18, the backing layer 44 may be installed on
the truss assemblies 12, followed by the liner system (e.g., such
as liner 20). The liner 20 is coupled to the top panels 30 and
planar panels 26 as noted above. Thus, the liner 20 covers the
planar panels 26 and also defines the base 40 of the storage area
16. The particular configuration of the liner system, including the
number of layers of liner to be utilized and installed, is
determined in part by the material being stored, environmental
regulations for storing such material, and other structural and
safety considerations, as noted above.
[0060] Once the containment system 10 has been installed on site,
the storage area 16 may be filled with material (fluid or granular)
as needed for the particular application. As the storage area 16 of
the system 10 is filled with the material, a horizontal load from
the weight of the material is transferred outwardly (shown by
outwardly extending forces F1 in FIG. 3) through the truss
assemblies 12 and into the load transfer rings 56, and then to the
high strength steel tension bands 18. As the height of the stored
material is increased within the storage area 16, the tension
forces within the bands 18 are increased. In addition, the slope of
the outer faces 28 of the planar panels 26 imparts a vertical load
or downward force F2 by the truss assemblies 12 so that the weight
of the material within the storage area 16 is directed downwardly
and into the ground G, thereby providing stability to the
containment system 10.
[0061] The containment system 10 may be utilized on the site until
storage at the site is no longer required. After the system 10 is
no longer needed at the site, and the storage area 16 is emptied of
any material therein, the system 10 may be easily disassembled and
relocated to a different site and/or stored for future use. The
liner system (e.g., backing layer 44 and liner 20) may be
transported away for further use, or discarded. The bands 18 may
then be unstressed and removed from the load transfer rings 56, and
either salvaged or discarded. The truss assemblies 12 may then be
disassembled and/or relocated to another site, where the system 10
may be readily reassembled for further use.
[0062] Having generally described the invention, the same will be
more readily understood through reference to the following example,
which is provided by way of illustration and is not intended to be
limiting of the present invention.
EXAMPLE
[0063] 1.25 Million Gallon (30,000 bbl) Design Specifications:
[0064] Panel Configuration: [0065] Outside Diameter=160 ft [0066]
Average Inside Diameter=150 ft [0067] Panel Length=15 ft-9 in
[0068] Panel Width at Base=6 ft-0 in [0069] Panel Width at Top=2
ft-0 in [0070] Number of panels=32 [0071] Allowable Fluid Storage
Height=10 ft (2 ft Freeboard) [0072] Design Fluid Storage Height=12
ft (Load Factor of Safety=1.2) [0073] Fluid Density=64 pcf [0074]
Panel Loading=96 pcf (Load Factor of Safety=1.5) [0075] Truss
Chords=Min grade SYP No 2 (Some Pressure Treated) [0076] Truss
Webs=Min Grade SPF No 2 (Some Pressure Treated) [0077] Truss
Connections=TPA rated plates suitable for use with PT Material
[0078] Plywood Sheeting=APA Rated Struct I sheeting, T & G
(Some Pressure Treated)
[0079] 7 Strand Steel Pre-stressing/Post-tensioning Cables: [0080]
f.sub.pu=270 ksi [0081] Nominal Diameter (in)=0.6 [0082] Area,
A.sub.ps (sq. in)=0.215 [0083] Weight (plf)=0.74 [0084] 0.7
f.sub.pu*A.sub.ps=40.7 kips (Resistance Factor of Safety=1.3)
[0085] 50 mil protective sheathing
[0086] Liner System: [0087] Geotextile Fabric: 10 oz heavy weight,
needle punched, non-woven, self-venting fabric [0088] Liner
Material: 30 mil LLDPE, scrim reinforced, UV stabilized, 20 year
rated material [0089] Geocomposite Material: 200 mil drainage
material with 6 oz needle punched, non-woven, self-venting fabric
on each side.
[0090] System Features: [0091] Fully supported liner system [0092]
Zero ground penetrations [0093] Above ground system provides
minimal earth disturbance [0094] Low ground pressures, less than
650 psf [0095] All system layers are self-venting [0096] Integrated
leak detection system
[0097] It should be understood that the example disclosed above is
provided for purposes of illustration only, and the present
invention is not so limited. A larger or smaller containment system
may be provided as required by the particular application. For
example, as disclosed above, a storage tank able to contain 3
million gallons or more of material may be provided. Accordingly,
the specific dimensions and system capabilities noted in the
example above are exemplary only.
[0098] All publications and patents mentioned in this specification
are herein incorporated by reference to the same extent as if each
individual publication or patent application was specifically and
individually indicated to be incorporated by reference in its
entirety. While the invention has been described in connection with
specific embodiments thereof, it will be understood that it is
capable of further modifications and this application is intended
to cover any variations, uses, or adaptations of the invention
following, in general, the principles of the invention and
including such departures from the present disclosure as come
within known or customary practice within the art to which the
invention pertains and as may be applied to the essential features
hereinbefore set forth.
* * * * *