U.S. patent application number 11/906260 was filed with the patent office on 2008-04-03 for gravel bag and method for protecting and exit point for stormwater.
Invention is credited to Cecil Pershing Cole, Richard Evan Quinley.
Application Number | 20080080936 11/906260 |
Document ID | / |
Family ID | 39261367 |
Filed Date | 2008-04-03 |
United States Patent
Application |
20080080936 |
Kind Code |
A1 |
Quinley; Richard Evan ; et
al. |
April 3, 2008 |
Gravel bag and method for protecting and exit point for
stormwater
Abstract
A gravel bag manufactured from a single layer of a heavy-duty
geotextile composite material (also referred to as
"geo-composite"), said layer comprising a closure device resistant
to opening as pressure is applied from within. The geo-composite
material is formed by affixing at least two fabrics that together
complement each other's performance. The overall structure allows
for a single composite geotextile fabric that is low-slip, low
cost, offers effective padding, has a high tensile strength, is
puncture and tear resistant, and that has low elongation
properties. In use, the single layer geo-composite gravel bag
significantly outperforms all other single layer and multiple layer
geo-composite gravel bags currently in use.
Inventors: |
Quinley; Richard Evan;
(Roseville, CA) ; Cole; Cecil Pershing;
(Sacramento, CA) |
Correspondence
Address: |
MATHEW J. TEMMERMAN
423 E. STREET
DAVIS
CA
95616
US
|
Family ID: |
39261367 |
Appl. No.: |
11/906260 |
Filed: |
September 29, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60848462 |
Sep 29, 2006 |
|
|
|
60898078 |
Jan 29, 2007 |
|
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Current U.S.
Class: |
405/302.7 |
Current CPC
Class: |
E02B 3/127 20130101;
E02D 29/0291 20130101; E02D 31/06 20130101 |
Class at
Publication: |
405/302.7 |
International
Class: |
E02D 31/06 20060101
E02D031/06 |
Claims
1. An improved gravel bag for one of either filtering a flow of
water or diverting a flow of water, the improved gravel bag
comprising: a. a shell made from a non-woven geotextile
substantially tightly affixed to a woven geotextile; and b. an
internal space filled with gravel.
2. The improved gravel bag according to claim 1 wherein said
closure system further comprises: a. flexible material having a
first side and a second side, wherein said second side is longer
than said first side and said second side is folded onto itself to
create an internal flap having an inwardly facing side and an
outwardly facing side, said outwardly facing side further
comprising hook and loop type fasteners and releasably attached to
said first side; and b. internal contents substantially retained
inside said gravel bag, wherein said internal contents assert
pressure against said inwardly facing side, thereby pushing said
outwardly facing side more tightly against said first side.
3. The improved gravel bag according to claim 2 wherein said
non-woven geotextile is needle-punched through said woven
geotextile.
4. The gravel bag according to claim 1 wherein said geotextiles are
heavy-duty geotextiles.
5. The improved gravel bag according to claim 4 further comprising
a closure system.
6. The improved gravel bag according to claim 5 wherein said
closure system further comprises: a. flexible material having a
first side and a second side, wherein said second side is longer
than said first side and said second side is folded onto itself to
create an internal flap having an inwardly facing side and an
outwardly facing side, said outwardly facing side further
comprising hook and loop type fasteners and releasably attached to
said first side; and b. internal contents substantially retained
inside said gravel bag, wherein said internal contents assert
pressure against said inwardly facing side, thereby pushing said
outwardly facing side more tightly against said first side.
7. The improved gravel bag according to claim 6 wherein said
non-woven geotextile is needle-punched through said woven
geotextile.
8. An improved gravel bag for one of either filtering a flow of
water or diverting a flow of water, the improved gravel bag
comprising a closure system further comprising: a. flexible
material having a first side and a second side, wherein said second
side is longer than said first side and said second side is folded
onto itself to create an internal flap having an inwardly facing
side and an outwardly facing side, said outwardly facing side
further comprising hook and loop type fasteners and releasably
attached to said first side; and b. internal contents substantially
retained inside said gravel bag, wherein said internal contents
assert pressure against said inwardly facing side, thereby pushing
said outwardly facing side more tightly against said first
side.
9. The improved gravel bag according to claim 8 wherein said gravel
bag comprises a shell made from a non-woven geotextile
substantially tightly affixed to a woven geotextile and an internal
space filled with gravel.
10. The improved gravel bag according to claim 8 wherein said hook
and loop type fasteners are arranged into at least two rows.
11. The improved gravel bag according to claim 10 wherein said
gravel bag comprises a shell made from a non-woven geotextile
substantially tightly affixed to a woven geotextile and an internal
space filled with gravel.
12. The gravel bag according to claim 11 wherein said geotextiles
are heavy-duty geotextiles.
13. The improved gravel bag according to claim 12 wherein said
non-woven geotextile is needle-punched through said woven
geotextile.
Description
RELATED APPLICATION
[0001] This application claims priority from U.S. provisional
application with Ser. No. 60/848,462, which was filed on 29 Sep.
2006, and U.S. provisional application with Ser. No. 60/898,078,
which was filed on 29 Jan. 2007. The disclosures of those
provisional applications are incorporated by reference herein as if
set out in full.
FIELD OF THE INVENTION
[0002] The present invention relates to construction sites, and
particularly methods for regulating construction site stormwater
runoff.
GENERAL BACKGROUND
[0003] The flow of water over land from rain, snowmelt, manmade
means such as irrigation and other sources is termed "runoff".
Oftentimes, and more particularly at construction sites, the runoff
rate exceeds the rate of water infiltration to the ground. Further,
water that has infiltrated an up-slope portion of a hill may flow
through the soil and exfiltrate from the soil further down, adding
to the volume of runoff. Finally, because many construction sites
are in urban areas, the effect of urbanization from structures such
as pavements and buildings further prevent infiltration of excess
water to the soil.
[0004] Runoff is one of the leading contributors to erosion.
Sediment and any other pollutants picked up by runoff are washed
downstream, often causing environmental damage, ecosystem
disturbances, aesthetic problems, and even groundwater
contamination in the process. Soil particles in runoff typically
range from about 0.001 millimeter to 1.0 millimeter in diameter.
Larger particles generally either are not picked up or settle out
from the moving waters, while smaller particles stay suspended in
the water column.
[0005] Because of the problems associated with runoff, several
means of mitigation and treatment are currently employed.
Regulations on urbanization and development, sediment control
devices, flood control programs and landscape maintenance
techniques are now commonplace. One technique commonly used at
construction sites is erosion control devices. As the U.S.
Environmental Protection Agency and other more local regulatory
entities have tightened the rules regarding runoff at construction
sites, adequate performance of sediment control devices employed
must be maintained to stay in compliance, and to avoid fines.
[0006] Sediment and erosion control devices have been used for
centuries by farmers protecting their soil resources from washing
away. Generally, erosion control involves the creation of a
physical barrier to absorb some of the energy in the flowing water
that causes the erosion. They also include filters to prevent
sediment from washing away. One type of physical barrier commonly
used in construction sites today is the gravel bag. A gravel bag is
a bag filled with crushed rock, gravel, or sand, and is designed
for installation across a slope to intercept runoff, reduce water
flow velocity, cause ponding and provide for the settling and
removal of sediment.
[0007] Gravel bags are also commonly used at construction sites to
slow the flow of water entering into storm drain inlets. Because
storm drain inlets are oftentimes on the street or otherwise in the
middle of the active construction sites, they are often in the path
of both regular and construction vehicle traffic. It can be
expected, then, that multiple crushing impacts will be generated on
the gravel bags by these vehicles. Because gravel bags are
typically filled with crushed aggregate (gravel), which is often
very abrasive, jagged, and sharp, the wear on the bags is quite
high. Friction from the sliding effect of vehicle traffic is also a
major contributor to gravel bag failures. When a gravel bag fails,
it can cause crushed aggregate and material trapped in the bag to
spread around the area, which in many cases is a city street or
even the drain inlet sought to be protected. Materials discharged
down a drain inlet and into waterways cause even more destruction.
Due to these factors, the lifespan of conventional existing gravel
bag products is on the order of weeks to several months when used
in high traffic areas. The cost to constantly replace such gravel
bags is high.
[0008] Conventional gravel bags are also prone to slippage from
contact with vehicles, displacing the bags from their desired
location. In order for a gravel bag to be effective at protecting a
drain inlet it must be in direct contact with the curb so as to
prevent sediment from having a direct flow into the drain inlet.
Even the smallest of gaps can cause the gravel bags to become
completely ineffective in this regard. Because conventional gravel
bags are slippery in nature they can be easily moved by contact
with vehicles and construction equipment. Even if the bag does not
fail as described previously, it may be displaced, causing a street
hazard and allowing sediment to wash into a drain inlet.
[0009] There is thus a need for in inexpensive, slip-resistant,
highly durable gravel bag solution that does not need frequent
replacement. The gravel bag must be able to withstand a high number
of vehicular impacts, while remaining largely in the same position,
and additionally should be inexpensive and simple to
manufacture.
DESCRIPTION OF THE PRIOR ART AND OBJECTIVE OF THE INVENTION
[0010] Numerous technologies and advancements in gravel bag
construction have been developed in an attempt to solve the above
problems. To that end, there are currently four kinds of gravel
bags commonly used, each with advantages and disadvantages.
[0011] As a first type of bag, burlap or woven polypropylene bags
can be filled with sand or gravel and are an inexpensive gravel bag
solution. The drawbacks are that they break easily, and as few as 1
to 2 vehicle impacts can cause the sharp edges of the gravel to
tear through them, or the seams or closure to fail, causing hazards
and the added expense of maintenance and replacement. They also
slip easily upon vehicle impact. Additionally, during the time when
they are broken, the construction site may be out of compliance
with local and federal regulations, potentially subjecting the
construction site to heavy environmental fines. The advantage to
this method is that they bags are very inexpensive, and if
vehicular traffic is light enough, they can be replaced cheaply on
an as-needed basis.
[0012] Second, gravel bags made from woven or knitted geotextile
materials may be used. These bags are generally made from a single
layer of 4 to 6-oz per square/yard knitted or woven fabric. These
bags are stronger than their burlap or woven polypropylene
counterparts. They too fall short in vehicular traffic areas,
breaking after between 1 to 10 vehicle impacts. In these bags, a
lack of padding allows the edges of rock to tear or cut through the
fabric upon vehicular impact. Another drawback to these bags are
that they slide easily, allowing the bags to move out of place, and
also generating dry friction that may lead to premature breakage
and similar environmental problems as described above. The
life-span of this type of bag is on the order of a few weeks to a
month in high traffic areas.
[0013] Third, multiple layer gravel bags are made from several
layers of knitted fabric with padded layers between them. The
padded layers serve to cushion the fabric from the abrasiveness of
the rock upon vehicle impact with the bag. Bags of this sort are
typically constructed of an inner bag made from a 4 to 6-oz/square
yard knitted shade cloth with a zipper or sewn closure, a middle
layer of foam, straw for cushioning, and an outer bag also made
from a 4 to 6-oz/square yard knitted shade cloth. A closure made
from a zipper or hook and loop type fastener secures the gravel
inside the bag. This type of bag is more durable than those
previously described, but can still break under moderate vehicle
traffic. Disadvantages to this type of bag are that the bag is
complicated and thus, expensive to manufacture, requiring that each
layer be sewn separately before being combined together.
Additionally, the bag typically has the requirement of being filled
smooth gravel because the inner layers of the bag is more prone to
wear from sharp rock, the closure of the bag is often unusable
after repeated use, prompting a need for replacement of the entire
bag, and the bags are prone to slipping, causing both dry friction
and the displacement of the bag from its intended location.
Although this product is expensive, it does represent the most
effective measure to date for a durable gravel bag able to
withstand multiple vehicular impacts, it still only has a limited
effective lifespan of 1 to 6 months in high traffic areas, breaking
after 10 to 30 vehicle impacts.
[0014] Nonwoven bags are a fourth solution. These bags are commonly
made from a nonwoven polypropylene or polyester geotextile. This
type of bag is particularly slip resistant, but lacks significant
tensile strength and puncture resistance against vehicular impacts.
Because of this, it is only a short-term measure for erosion and
sediment control, requiring replacement after several weeks or 1 to
5 vehicle impacts.
[0015] It is thus an objective of the present invention to provide
for a high strength gravel and durable gravel bag that is able to
withstand the vehicular impacts associated with high traffic
areas.
[0016] It is a second objective of the present invention to provide
a means for closing a gravel bag that will not be destroyed by the
vehicular impacts associated with high traffic areas.
[0017] It is a third objective of the present invention to provide
a gravel bag less prone to slipping out of place than conventional
gravel bags.
[0018] It is a fourth objective of the invention to provide the
above objectives through a simple and low cost design.
[0019] Additional objects and advantages of the present invention
will become obvious to the reader and it is intended that these
objects and advantages be within the scope of the present
invention.
BRIEF DESCRIPTION OF THE FIGURES
[0020] The foregoing aspects and many of the attendant advantages
of the invention will become more readily appreciated as the same
becomes better understood by reference to the following detailed
description, when taken in conjunction with the accompanying
drawings, wherein:
[0021] FIG. 1 is a perspective environmental view of two of
applicant's improved gravel bags placed on either side of a drain
inlet.
[0022] FIG. 2 is a plan view of applicant's gravel bag according to
a first configuration of the invention. Cross sectional lines are
shown, corresponding to figure numbers associated therewith.
[0023] FIG. 3 is a cross sectional view taken along cut line 3-3 in
FIG. 2 depicting the gravel bag according to a first configuration
wherein the bag is empty.
[0024] FIG. 4 is a cross sectional view matching up with FIG. 3
wherein said gravel bag is depicted according to a second
configuration filled with gravel.
[0025] FIG. 5 is a cross sectional view taken along cut line 5-5 in
FIG. 2 depicting the gravel bag according to the first
configuration.
[0026] FIG. 6 is a perspective view depicting the geo-composite
material making up gravel bag. Cross sectional lines are shown,
corresponding to figure numbers associated therewith.
[0027] FIG. 7 is a cross sectional view taken along cut line 7-7 in
FIG. 6.
[0028] FIG. 8 is a detailed view of the circle 8 in FIG. 7.
SUMMARY OF THE INVENTION
[0029] The present invention is a gravel bag manufactured from a
single layer of a heavy-duty geotextile composite material (also
referred to as "geo-composite") comprising a closure device
resistant to opening as pressure is applied from within. The
geo-composite material is formed by combining several fabrics that
together complement each other's performance. The overall structure
allows for a single composite geotextile fabric that is low-slip,
low cost, offers effective padding, has a high tensile strength, is
puncture and tear resistant, and that has low elongation
properties.
[0030] In use, the single layer geo-composite gravel bag has been
shown to significantly outperform all other single layer and
multiple layer geo-composite gravel bags currently in use.
DETAILED DESCRIPTION OF THE INVENTION
[0031] The present invention is an improved gravel bag 1 (see FIG.
1) manufactured from a single layer of a heavy-duty geotextile
composite material (also referred to as "geo-composite") comprising
a closure device resistant to opening as pressure is applied from
within. For purposes of this patent application, the term composite
material shall refer to a material made from two or more
constituent materials with at least two substantially different
mechanical properties, substantially and tightly affixed to one
another across a majority of their sheet like structure, and which
remain separate and distinct within the finished structure.
[0032] Referring now to FIG. 3, in a preferred embodiment of the
invention, the first material is a nonwoven material 40 created
through the compression of loose threads. See FIG. 6. This material
is felt-like in feel and appearance, and comprises flexible yet
strong materials such as polypropylene or polyester (2 to 15-oz per
sq-yd, preferably 6-oz per sq-yd), such as various types of Daltex
polypropylene, which is readily available. In this preferred
embodiment, the second material is a slit tape woven material 42
comprising ribbon like elements woven together. The elements must
be flexible, yet strong. In a preferred embodiment of the invention
plastic elements such as 5 to 15-oz per sq-yd polypropylene or
polyethylene are used. In a preferred embodiment, 10 oz per sq-yd
polypropylene or polyethylene is used, however, other durable
flexible materials may be used as well. As shown best in FIG. 6 and
8, the elements comprise a first slit tape 43 woven with a second
slit tape 44 into a mesh-like material.
[0033] Referring now to FIGS. 6-8, the geo-composite material is
shown in detail. The nonwoven material 40 and the woven material 42
are in substantially continuous contact with one another across
their sheet like structure to create a material sewn and folded
into the shape of gravel bag 1. See also FIG. 1. The materials are
affixed to one another as is commonly known in the art, with
methods including but not being limited to needle punching, gluing,
fusing, and sonic welding. In the preferred embodiment of the
invention and as shown in FIGS. 7 and 8, the nonwoven material 40
is needle punched through the woven material 42. Threads 41 of the
nonwoven material are shown in FIG. 8 protruding through the woven
material. It is noted that threads 41 puncture through the woven
material 40 both between junctions of weaving and directly through
the individual tapes that are woven together. The finished
geo-composite can range between 7-oz to over 30-oz per sq-yd, but
in a preferred embodiment weighs 16-oz per sq-yd. In an alternative
embodiment of the invention, a woven monofilament structure is used
rather than a slit tape woven structure.
[0034] Together, the nonwoven material 40 and the woven material 42
make up the geotextile, which has properties of a permeable textile
material that may be used for filtration, drainage, separation,
reinforcement and stabilization. The woven portion and the
non-woven portion work together to give rise to many of the
advantageous properties of the present invention. First, the
non-woven material 40 gives the gravel bag properties of padding
and slip resistance. These properties are present on both sides of
the finished geo-composite fabric because in the needle punching
process the non-woven is significantly forced through the woven
material to the other side. See generally FIGS. 6 and 7. Second,
the woven material 42 gives the gravel bag the properties of high
tensile strength, low elongation tendencies, puncture resistance
and tear resistance.
[0035] The needle punching process provides a fabric where the
non-woven geotextile has significant volume on both sides and
in-between the weave of the woven fabric. After needle punching the
material is very stable and difficult to separate.
[0036] Because the gravel bag material is manufactured from a
single layer composite it is significantly less expensive to
manufacture than conventional multiple layer gravel bags, yet still
offers significantly improved performance.
[0037] A second important property of the applicant's gravel bag is
its unique closure system, which is an internal envelope style
having a hook and loop closure. The closure is formed providing for
the gravel bag a first side 10 and a second side 20, wherein said
second side is longer than said first side. See FIG. 3. The second
side 20 is folded onto itself at flap fold 23 so that the second
side outer surface 21, containing two rows of hook and loop
fasteners 30 and 31, is abutting two rows of complimentary hook and
loop fasteners 32 and 33 on a first side inner surface 12 of said
first side 10, much like a folded plastic sandwich bag. A second
side outer surface 21 and a first side outer surface 11 are exposed
to the environment outside the gravel bag. Referring briefly to
FIG. 5, second side 20 and first side 10 each comprise a fold,
shown as reference numbers 15 and 25, referring to first side fold
and second side fold respectively.
[0038] Referring back to FIGS. 3 and 4. The gravel bag is sealed
closed with said first row of hook and loop fasteners 31 and said
second row of hook and loop fasteners 32. Both rows of fasteners
are sewn onto the portion of the second side outer surface 21 of
the second side 20, above said flap fold 23. A first row of
complementary hook and loop fasteners 33 and a second row of
complementary hook and loop fasteners 34 are sewn into said first
side inner surface 12 and said first side 10. Both rows of hook and
loop fasteners are are substantially aligned with their
complementary counterparts to allow normal use and operation of the
hook and loop fasteners as is well known in the art.
[0039] Because second side 20 is folded at flap fold 23 back onto
itself, it may be constructed from one piece of material, thereby
reducing the cost of construction. This envelope hook and loop type
of closure allow the bags to be filled to 100% of their volume,
giving them a larger surface area and larger core space than most
of the other similar products. The core space of the bag is in a
preferred embodiment filled with gravel 5 but may in alternative
embodiments be filled with crushed aggregate, sand, smooth rock,
compost, wood chips, crumb rubber, and mixtures of all of the
above. The closure is very strong because under a crushing force,
such as by a vehicle, the pressure of the gravel 5 is not exerting
a great force on the opening or closure of the bag, thereby tending
to cause it to open. Instead, the pressure is primarily exerted on
the second side inner surface 22. This unique closure adds strength
to the bag and allows for potential re-use because the bag can be
emptied of gravel 5, stored, and re-filled on another job site.
Additionally, if the opening does fail at the hook and fastener
closure, it can simply be resealed.
[0040] The overall structure allows for a single composite
geotextile fabric that is low-slip, low cost, offers effective
padding, has a high tensile strength, is puncture and tear
resistant, and that has low elongation properties. In use, the
single layer geo-composite gravel bag has been shown to
significantly outperform all other single layer and multiple layer
geo-composite gravel bags currently in use.
[0041] The applicant has demonstrated that the bag can be utilized
for long periods of time in areas of extreme vehicular traffic.
Impacts from traffic (both regular and construction) have little
effect, both on the placement of the bag and the bag's condition.
Testing has shown that the improved gravel bag routinely withstands
hundreds of vehicular (both regular and construction) impacts, and
in many instances over one thousand vehicular impacts (both regular
and construction). The improved gravel bag is thus between four and
ten times more durable than conventional gravel bags currently in
use.
[0042] The expected life of the product is entire length of most
construction projects, or between 6 months and 2 years. Testing has
yielded failure rates under 1% after 6 months and under 5% after 12
months. This durability and the properties of the bags
significantly reduce maintenance and replacement costs when
compared to existing products. In most construction projects, the
need to replace the product is completely eliminated. Because of
the durability of the bag and relatively low cost to manufacture,
this improved gravel bag offers a high value and significantly
decreases overall costs over the duration of construction. They
gravel bag can also be re-used, further reducing overall costs.
[0043] In an alternative embodiment the bag is not re-sealable, and
does not utilize the hook and loop type fasteners. (Embodiment not
shown). Instead, the two sides of the bag can be sewn, fused, or
glued together permanently.
[0044] With respect to the above description then, it is to be
realized that material disclosed in the applicant's drawings and
description may be modified in certain ways while still producing
the same result claimed by the applicant. Such variations are
deemed readily apparent and obvious to one skilled in the art, and
all equivalent relationships to those illustrated in the drawings
and equations and described in the specification are intended to be
encompassed by the present invention.
[0045] Therefore, the foregoing is considered as illustrative only
of the principles of the invention. Further, since numerous
modifications and changes will readily occur to those skilled in
the art, it is not desired to limit the invention to the exact
disclosure shown and described, and accordingly, all suitable
modifications and equivalents may be resorted to, falling within
the scope of the invention.
* * * * *