U.S. patent application number 13/914655 was filed with the patent office on 2013-12-19 for yieldable mine roof support.
The applicant listed for this patent is FCI Holdings Delaware, Inc.. Invention is credited to Dakota Faulkner, John C. Stankus, Bevan G. Thompson, Joshua D. Verbano.
Application Number | 20130336727 13/914655 |
Document ID | / |
Family ID | 49756048 |
Filed Date | 2013-12-19 |
United States Patent
Application |
20130336727 |
Kind Code |
A1 |
Faulkner; Dakota ; et
al. |
December 19, 2013 |
YIELDABLE MINE ROOF SUPPORT
Abstract
A mine roof support includes a rigid body having a first end and
a second end and defining an interior space, a cementitious
material positioned within the interior space of the body and a
plurality of support members extending circumferentially around the
body and engaging an outer surface of the body. A method includes
providing a mine roof support comprising a rigid body having a
first end and a second end, a cementitious material positioned
within an interior space defined by the body, and a support member
extending circumferentially around the body and engaging an outer
surface of the body. The method also includes selecting a load
capacity and elongation value of the support member to provide
controlled yieldable confinement of the mine roof support during
loading of the mine roof support.
Inventors: |
Faulkner; Dakota; (New
Kensington, PA) ; Stankus; John C.; (Canonsburg,
PA) ; Verbano; Joshua D.; (Pittsburgh, PA) ;
Thompson; Bevan G.; (Pittsburgh, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FCI Holdings Delaware, Inc. |
Wilmington |
DE |
US |
|
|
Family ID: |
49756048 |
Appl. No.: |
13/914655 |
Filed: |
June 11, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61659758 |
Jun 14, 2012 |
|
|
|
Current U.S.
Class: |
405/288 |
Current CPC
Class: |
E21D 15/005 20130101;
E21D 15/483 20130101 |
Class at
Publication: |
405/288 |
International
Class: |
E21D 15/00 20060101
E21D015/00 |
Claims
1. A mine roof support, comprising: a rigid, generally circular
body having a first end and a second end, an outer surface, and an
inner surface defining an interior space; and a support member
extending circumferentially around the body and engaging an outer
surface of the body.
2. The mine roof support of claim 1, further including a
cementitious material positioned within the interior space of the
body, wherein the cementitious material has a strength in the range
of about 200 psi to about 900 psi.
3. The mine roof support of claim 1, further including additional
support members extending circumferentially around the body.
4. The mine roof support of claim 3, wherein the support members
are spaced apart along the body.
5. The mine roof support of claim 1, wherein the support member
extends horizontally about the body.
6. The mine roof support of claim 1, wherein the support member
extends helically about the body.
7. The mine roof support of claim 1, wherein the support member is
formed of a polyester material or a metal material.
8. The mine roof support of claim 1, wherein the body is generally
cylindrical.
9. The mine roof support of claim 1, wherein the support member has
a width in the range of about 2 inches to about 5 inches.
10. A mine roof support, comprising: a rigid body having a first
end and a second end, and defining an interior space; a
cementitious material positioned within the interior space of the
body; and a plurality of support members extending
circumferentially around the body and engaging an outer surface of
the body.
11. The mine roof support of claim 10, further including additional
support members extending circumferentially around the body.
12. The mine roof support of claim 11, wherein the support members
are spaced apart along the body.
13. The mine roof support of claim 1, wherein the support member
extends horizontally about the body.
14. The mine roof support of claim 1, wherein the support member
extends helically about the body.
15. The mine roof support of claim 1, wherein the support member is
formed of a polyester material or a metal material.
16. The mine roof support of claim 1, wherein the body is generally
cylindrical.
17. The mine roof support of claim 1, wherein the support member
has a width in the range of about 2 inches to about 5 inches.
18. The mine roof support of claim 1, wherein the cementitious
material has a strength in the range of about 200 psi to about 900
psi.
19. A method comprising: providing a mine roof support comprising a
rigid body having a first end and a second end, a cementitious
material positioned within an interior space defined by the body,
and a support member extending circumferentially around the body
and engaging an outer surface of the body; and selecting a load
capacity and elongation value of the support member to provide
controlled yieldable confinement of the mine roof support during
loading of the mine roof support.
20. The method of claim 19, further including: providing additional
support members extending circumferentially around the body; and
spacing the support members along a length of the body.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Application No. 61/659,758, filed Jun. 14, 2012, the entire content
of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] This invention is related to a mine roof support and, more
particularly, to a yieldable mine roof support formed from a pipe
that receives cementitious material.
[0003] Cribbing is frequently used to provide support in
underground mine openings. One type of cribbing is formed using a
standard corrugated culvert pipe that is filled with a cementitious
material that is allowed to cure such that the pipe becomes a
load-bearing structure. The culvert pipe is typically formed from
16 gauge galvanized steel sheet that is helically wound and joined
along a continuous seam. When the corrugated pipe support is placed
under a load, however, the corrugated pipe will eventually begin to
separate along the continuous seam as the load and deformation of
the pipe increases. The separation of the continuous seam typically
results in a loss of confinement, thereby reducing the
load-carrying capacity of the support.
SUMMARY OF THE INVENTION
[0004] In accordance with an aspect of the invention, a mine roof
support includes a rigid, generally circular body having a first
end and a second end, an outer surface, and an inner surface
defining an interior space. The mine roof support also includes a
support member extending circumferentially around the body and
engaging an outer surface of the body.
[0005] In accordance with another aspect of the invention, a mine
roof support includes a rigid body having a first end and a second
end and defining an interior space, a cementitious material
positioned within the interior space of the body and a plurality of
support members extending circumferentially around the body and
engaging an outer surface of the body.
[0006] In accordance with another aspect of the invention, a method
includes providing a mine roof support comprising a rigid body
having a first end and a second end, a cementitious material
positioned within an interior space defined by the body, and a
support member extending circumferentially around the body and
engaging an outer surface of the body. The method also includes
selecting a load capacity and elongation value of the support
member to provide controlled yieldable confinement of the mine roof
support during loading of the mine roof support.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is an elevational view of a mine support, in
accordance with an aspect of the invention.
[0008] FIG. 2 is a cross-sectional view of the mine support shown
in FIG. 1, in accordance with an aspect of the invention.
[0009] FIG. 3 is a graph of testing results of mine supports
showing load versus deflection, in accordance with an aspect of the
invention.
[0010] FIG. 4 is an elevational view of another mine support, in
accordance with an aspect of the invention.
[0011] FIG. 5 is an elevational view of n additional mine support,
in accordance with an aspect of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0012] The present invention will now be described with reference
to the accompanying figures. For purposes of the description
hereinafter, the terms "upper", "lower", "right", "left",
"vertical", "horizontal", "top", "bottom", and derivatives thereof
shall relate to the invention as it is oriented in the drawing
figures. However, it is to be understood that the invention may
assume various alternative variations and step sequences, except
where expressly specified to the contrary. It is to be understood
that the specific apparatus illustrated in the attached figures and
described in the following specification is simply an exemplary
embodiment of the present invention. Hence, specific dimensions and
other physical characteristics related to the embodiments disclosed
herein are not to be considered as limiting.
[0013] Referring to FIGS. 1 and 2, one aspect of a mine support 10
includes a rigid body 12 having a first end 14 and a second end 16,
and defining an interior space 18. The body 12 is generally
cylindrical and includes an inner surface 20 and an outer surface
22. In one aspect, the body 12 may be, for example, a corrugated
metal pipe formed from 16 gauge galvanized steel sheet that is
helically wound and joined along a continuous seam (seam not
shown), although other suitable arrangements for the body 12 may be
utilized such as, for example, bright steel pipe (uncorrugated) or
tubing of suitable dimensions.
[0014] The mine support 10 further includes a support member 26
that extends circumferentially around the body 12 and is configure
to contact or engage the outer surface 22 of the body 12. As shown
in FIG. 1, the mine support 10 includes three support members 26
spaced from each other and generally positioned adjacent to the
second end 16 of the body 12. The mine support 10, however, may
include one or more support members 26. The one or more support
members 26 may also be positioned at the first end 14 of the body
12, the second end 16 of the body 12, or any position intermediate
the first and second ends 14, 16 of the body 12.
[0015] The support member 26 may be formed from a polyester fabric
strap that is positioned around and in contact with or engaged with
the outer surface 22 of the body 12. The polyester fabric strap may
have, for example, a 4,000 lbf peak load and have generally high
elongation properties, such as, for example, 14% elongation at
4,000 lbf load.
[0016] The support member 26 may also be formed from a metal
material, such as, for example, a steel strap, such as in the form
of a steel pallet strap, having, for example, a 3,000 lbf peak load
and generally low elongation properties. In one aspect, a steel
pallet strap having 3% elongation at 12,000 lbf load.
[0017] Accordingly, the support member 26 may be formed from a
strap of material having, in one example, a first end 27 and a
second end 29, with the first end 27 secured to the strap or the
second end 29 via any suitable fastening element 31. The support
member 26 may also be provided as a single piece of material
extending from the first end 14 to the second end 16 of the body
12. In one aspect, the support members 26 may have a width W of 2-5
inches. Other suitable support members 26 may also be utilized
having various dimensions, configurations, and physical
properties.
[0018] Referring again to FIGS. 1 and 2, in use, the second end 16
of the body 12 is engaged with a roof portion 30 of a mine opening
32, and the first end 14 of the body 12 is engaged with a floor
portion 34 of the mine opening 32. A cementitious material 36 is
received and contained within the interior space 18 of the body 12.
The mine support 10 may be installed as a completed unit, with the
body 12, support member 26, and cementitious material 36 forming an
integral support that is positioned within the mine opening 32. The
mine support 10 may also be installed as separate components. The
cementitious material 36 may be aerated cementitious filler having
a strength between 200-900 psi, although other suitable
cementitious materials may be utilized. In one aspect, the
cementitious material 36 has a strength of 350-400 psi.
[0019] Under loading and vertical displacement of the mine support
10, the support member 26 is placed under load and increases the
confinement of the cementitious material 36, thereby increasing
peak load and residual loads. In particular, the support member 26
substantially minimizes the degree to which the body 12 separates
along its continuous seam and increases confinement by minimizing
the amount of fractured cementitious material 36 from leaving the
body 12. Thus, the mine roof support 10 has improved peak load and
residual loading compared to conventional mine roof supports.
Further, specific load capacity and elongation values of the
support member 26 may be selected to optimize the performance of
the mine support 10. As the mine support 10 undergoes deformation,
the body 12 will start to separate along its continuous seam which
is contained by the support member 26. The elongation value of the
support member 26 will affect the degree to which the cementitious
material 36 and body 12 will deform outward and the degree to which
the seam of the body 12 will separate. Accordingly, the support
member 26 along with the body 12 provides for controlled yieldable
confinement, which may be optimized by selecting the load capacity
and elongation values of the support member 26 alone or in
combination with the load capacity and/or elongation value (or
other physical properties) of the body 12. The circumference of the
body 12 may expand upon loading in addition to elongation of the
support members 26.
[0020] Referring to FIG. 3, mine supports 10 according to two
embodiments of the present invention were tested along with a
control. "Test A" tested a mine roof support 10, as described
above, with a single support member 26 formed from polyester fabric
placed one foot below the second end of the body. After 7 inches of
deformation, the support member 26 broke, resulting in a sudden
loss of confinement and its supporting capacity, as indicated at
point "X" on the curve for Test A. "Test B" tested a mine roof
support 10, as described above, with three spaced-apart support
members 26 formed from steel straps having a 3,000 lbf peak load.
As the mine roof support 10 was loaded, the three support members
26 broke during different points of deformation, which resulted in
higher peak and residual loads. The three straps broke at points
#1, #2, and #3 on the Test B curve. The support in Test C included
no confinement bands or support members 26. It should be
appreciated that prior to breakage of the support members 26 in
Tests A and B, the supports thereof exhibited continued increased
loading and 50-100% greater load than the support of Test C. In
addition, after breakage of the support member in Test B and of all
the support members in Test A, the performances of the mine
supports A and B were similar to that of mine support C. These
tests demonstrated that the performance of a conventional mine roof
support can be manipulated through the use of one or more support
members 26. By adjusting the type and number of support members 26,
the performance of the mine roof support 10 can be tuned to achieve
a specific response curve. The support member 26 may be formed from
a number of different straps having various load-carrying
capacities and elongation properties to assist in fine tuning the
performance curve.
[0021] In one aspect of the invention, the mine support 10 provides
sequential confinement thereof. The body 12 may bulge or otherwise
yield followed by yielding of the support members 26, or support
members 26 may yield first followed by yielding of the body 12. It
has been found that the mine support 10 can exhibit at least 25%
reduction in height upon loading without failure.
[0022] FIG. 4 illustrates an additional mine support 110, in
accordance with another aspect of the invention. Mine support 110
includes a rigid body 112 having a first end 114 and a second end
116, and defining an interior space 118. The body 112 is generally
cylindrical and extends along a longitudinal axis A-A and includes
an inner surface 120 and an outer surface 122. In one aspect, the
rigid body 112 may be, for example, any suitable material having
sufficient mechanical properties for supporting a cementitous
material in the interior space 118. In another aspect, the outer
surface 122 may be generally smooth as illustrated in FIG. 4.
[0023] The mine support 110 further includes a plurality of support
members 126 that extend circumferentially around the body 112 and
configured to contact or engage the outer surface 122 of the body
112. As shown in FIG. 4, the mine support 110 includes four support
members 126 spaced apart from each other and generally positioned
along the length of the body 112. In one aspect, the support
members 126 extend horizontally about the body 112, e.g. generally
horizontal with respect to the roof portion 30 and/or the floor
portion 34 or generally perpendicular with respect to the
longitudinal axis A-A.
[0024] FIG. 5 illustrates an additional mine support 210, in
accordance with another aspect of the invention. Mine support 210
includes a rigid body 212 having a first end 214 and a second end
216, and defining an interior space 218. The body 212 is generally
cylindrical and extends along a longitudinal axis A-A and includes
an inner surface 120 and an outer surface 222. In one aspect, the
rigid body 212 may be, for example, any suitable material having
sufficient mechanical properties for supporting a cementitous
material in the interior space 218. In another aspect, the outer
surface 222 may be generally smooth as illustrated in FIG. 5.
[0025] The mine support 210 further includes a continuous support
member 226 that extends circumferentially around the body 212 and
configured to contact or engage the outer surface 222 of the body
212. As shown in FIG. 2, the support member 226 is configured to be
spaced apart generally positioned along the length of the body 212.
In one aspect, the support member 226 extends angularly or
helically about the body 212, e.g. generally angularly or helical
with respect to the roof portion 30 and/or the floor portion 34 or
generally angularly or helical with respect to the longitudinal
axis A-A.
[0026] While several aspects of the invention were described in the
foregoing detailed description, those skilled in the art may make
modifications and alterations to these aspects without departing
from the scope and spirit of the invention. Accordingly, the
foregoing description is intended to be illustrative rather than
restrictive.
* * * * *