U.S. patent application number 13/309726 was filed with the patent office on 2013-02-28 for impact resistant cambered lagging element.
The applicant listed for this patent is Erik Denver, Tyler Proffitt. Invention is credited to Erik Denver, Tyler Proffitt.
Application Number | 20130051931 13/309726 |
Document ID | / |
Family ID | 47743977 |
Filed Date | 2013-02-28 |
United States Patent
Application |
20130051931 |
Kind Code |
A1 |
Denver; Erik ; et
al. |
February 28, 2013 |
IMPACT RESISTANT CAMBERED LAGGING ELEMENT
Abstract
The present invention provides cambered impact resistant lagging
roof panels for an arch support assembly which is designed for
withstanding the effects of rock bursts in an underground mine. The
impact resistant panels are aligned in a parallel series with their
cambered faces facing upwardly and positioned transversely between
adjacent sets of steel arch supports of the assembly. The impact
resistant lagging panels are constructed as C-shaped metal channels
with their channel openings facing downward. The panels are
retained between adjacent beams under compression.
Inventors: |
Denver; Erik; (Keen
Mountain, VA) ; Proffitt; Tyler; (Pounding Mill,
VA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Denver; Erik
Proffitt; Tyler |
Keen Mountain
Pounding Mill |
VA
VA |
US
US |
|
|
Family ID: |
47743977 |
Appl. No.: |
13/309726 |
Filed: |
December 2, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61575726 |
Aug 26, 2011 |
|
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|
Current U.S.
Class: |
405/288 |
Current CPC
Class: |
E21D 11/155
20130101 |
Class at
Publication: |
405/288 |
International
Class: |
E21D 19/00 20060101
E21D019/00 |
Claims
1. An impact resistant lagging panel assembly comprising; spaced
parallel beams; and a parallel series of elongate impact lagging
panels cambered from end to end in the same direction of perceived
impact and positioned transversely to said beams and supported by
and between said beams.
2. The assembly of claim 1, wherein said panels are retained
between said beams under compression.
3. The assembly of claim 1, wherein said panels are metal C-shaped
channels with their camber extending away from the channel
opening.
4. The assembly of claim 3, wherein said panels are retained
between said beams under compression.
5. An arch support assembly for withstanding the effects of rock
burst in an underground mine, comprising: an aligned series of
spaced arch supports; and a parallel series of roof panels which
are upwardly cambered between the ends thereof and transversely
supported by and between said arch supports.
6. The assembly of claim 4, wherein said panels are retained
between said arch supports under compression.
7. The assembly of claim 5, wherein said cambered metal roof panels
are metal C-shaped channels with their channel openings facing
downward.
8. The assembly of claim 7, wherein said panels are retained
between said arch supports under compression.
9. An arch support assembly for withstanding the effects of rock
burst in an underground mine, comprising; an aligned series of
spaced arch supports, each support including a spaced pair of legs
and an upwardly cambered cap beam having opposite ends thereof
secured to upper ends of said legs; a parallel series of roof
panels which are upwardly cambered between their ends and
transversely supported by and between adjacent of said cap beams;
and tie rods tying said adjacent cap beams together with said roof
panels thereby retained between said cap beams under
compression.
10. The arch support assembly of claim 7, said cambered roof panels
are metal and configured as downwardly open C-shaped channels.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Application No. 61/575,726, filed 26 Aug. 2011, the entire content
of which is hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to mine roof
control, and more particularly, it is directed to adding stability
and maintaining the integrity of a steel support assembly or system
designed for withstanding the effects of rock bursts during impact
loading in an underground mine. Specifically, the invention
pertains to lagging panels for roof control in such steel support
assemblies or systems.
BACKGROUND OF THE INVENTION
[0003] As mining conditions continue to deteriorate due to
depletion of easily accessible reserves, arch support installation
is becoming more common. Currently all wide flange arch support
assemblies are rigid. Cambered arch support assemblies are
typically installed in an area where a roof fall has occurred and
loose debris has been removed. In order to protect miners from
secondary rock falls, arch support assemblies must be installed to
protect the miners using the travel way. The object is for the
cambered arch support system or assembly to absorb the impact of a
rock burst impact load.
[0004] Typically, when an underground mine experiences a roof fall,
the rock debris is removed from the area and the area of the roof
fall is bolted and backfilled to reduce the risk of further rock
fall. The process of bolting and backfilling the area of the roof
that experience roof fall, however, is a time consuming process
that requires the mine to stop production. In addition, backfill
material is costly and backfilling the large roof fall area can
become prohibitively expensive. Accordingly, steel arch support
assemblies are more currently utilized as a simple and reliable
system to protect personnel and moving vehicles from falling
rocks.
[0005] Generally, these rigid arch support assemblies incorporate a
roof structure spanning between adjacent arch supports of the
assembly as lagging panels which are intended to absorb the impact
loads from the falling rock. As an example, see the impact
resistant lagging assembly disclosed in U.S. Patent Application
Publication No. U.S. 2010/0266349, published on Oct. 21, 2010.
[0006] Presently, wide flange arch support assemblies deform when
an impact load is applied and the arch sets comprising the assembly
are compromised and cannot be preserved and therefore have to be
replaced. Currently all lagging elements (roof impact yielding
panels) used in these steel support systems have been designed
using static load conditions without attention to dynamic impact
loading. It is an object of the present invention to provide a
lagging element which allows the steel support system to absorb and
dissipate the impact energy from a mine roof fall.
[0007] The lagging elements currently used do not sustain impact
loading adequately; particularly if more than one impact occurs.
This usually results in a required replacement of the lagging
elements or panels, which can create unsafe working conditions.
SUMMARY OF THE INVENTION
[0008] The impact resistant lagging panel system of the present
invention is comprised of a parallel series of the elongate impact
lagging panels which are cambered (curved) from end to end whereby
the curvature of the panels protrudes or extends in the direction
of perceived impact from rock bursts. The lagging panels are
generally positioned transversely to and supported by and between
cap beams of the arch support assembly. The lagging panels are
preferably retained between the cap beams under compression and are
also preferably constructed of metal C-shaped channels with their
camber extending away from the channel opening.
[0009] The cambered lagging element of the present invention allows
the steel support system to absorb and dissipate the impact energy
from a mine roof fall. The cambered shape of the lagging element
allows for a spring like resistance when impact loading is
incurred. When the cambered lagging element of the present
invention is subjected to impact, structural integrity is
preserved.
[0010] The cambered lagging roof panel of the present invention is
useful in areas where the immediate mine roof is unbolted or has
the potential to become dislodged and fall on to the steel support
system. The cambered lagging elements of the present invention are
installed in the course (open area between steel support sets) to
provide a means for the steel support system to dissipate the
impact energy of falling rock from the mine roof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Other objects and advantages appear hereinafter in the
following description and claims. The accompanying drawings show,
for the purpose of exemplification, without limiting the scope of
the present invention or the appended claims, certain practical
embodiments of the present invention wherein:
[0012] FIG. 1 is an isometric view of the cambered impact resistant
lagging panel of the present invention; and
[0013] FIG. 2 is an isometric view of an arch support assembly
incorporating the cambered impact resistant lagging roof panels of
the present invention, with portions of the roof panels sectioned
away to expose the tie rods disposed thereunder.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
[0014] Referring to the drawings, the impact resistant lagging
panels 10 are elongate elements cambered from end to end in or
toward the direction of perceived impact. The panels 10 are
preferably constructed of metal and provided with a C-shaped
channel configuration with the camber extending away from the
channel opening as illustrated.
[0015] The cambered lagging panels 10 are incorporated into the
steel arch support assembly 11 shown in FIG. 2 as an aligned
parallel series of adjacent roof panels supported by and between
adjacent cambered cap beams 12. Tie rods 13 tie adjacent cap beams
12 together with the roof panels 10 thereby retained between the
cap beams 12 under compression. Portions of the assembly of roof
panels 10 is broken away in FIG. 2 to disclose tie rods 13.
However, most of the tie rods 13 in FIG. 2 are not visible because
they run under the C-shaped metal channels which form the lagging
elements or panels 10.
[0016] The cap beams 12 have their opposite ends secured to upper
ends of legs 14. The cap beams 10 and legs 14 are steel I-beams.
The bottom ends of legs 14 are in turn secured to and supported on
steel runner channels 15 which permits sliding of the entire arch
support assembly 11 along a ground surface as a unit.
[0017] The curved lagging members or panels 10 are formed through
conventional bending processes. The ends of the metal panels 10 are
cut in a manner to allow maximum contact to the outer resisting
surfaces, namely, the beam webs and flanges of the arch support set
16 being lagged. Once the arch support sets 16 are lagged 100%, the
cambered lagging elements or panels 10 are pulled into compression
via tie rods 13 between adjacent arch supports of sets 16, creating
the resistance required to allow the panels 10 to function most
effectively.
[0018] Once the panels 10 are pulled into compression using tie
rods 13 this creates maximum resistance on both ends of the
cambered lagging elements. This process allows any vertical loading
incurred to be partially transitioned axially into the lagging
panels 10, rather than strictly placing the panels 10 under bending
stress.
[0019] The impact resistant lagging panels 10 are cambered or
curved to allow spring-like resistance to dynamic loading. All
vertical forces incurred are partially transitioned into an axial
force, dampening bending stress effects. The enhanced integrity of
the cambered lagging of panels 10 lengthens the life span of the
panels 10 and the arch support set 16, minimizing replacement.
[0020] The lagging panels 10 are preferably constructed of steel.
However, other suitable materials may be substituted. In addition,
configurations other than the C-shaped channels may be
utilized.
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