U.S. patent application number 10/701289 was filed with the patent office on 2005-05-19 for fire barrier system for building panels.
This patent application is currently assigned to E.M.E.H., Inc.. Invention is credited to Barr, Roger.
Application Number | 20050102941 10/701289 |
Document ID | / |
Family ID | 34573315 |
Filed Date | 2005-05-19 |
United States Patent
Application |
20050102941 |
Kind Code |
A1 |
Barr, Roger |
May 19, 2005 |
Fire barrier system for building panels
Abstract
An expansion joint for building panels, such as concrete floor
slabs, comprises a U-shaped drape of a flexible, fire-resistant,
impermeable material such as stainless steel foil. The opposite
legs of the U-shaped drape are fastened between respective adjacent
slabs and a mat of expandable fire-resistant material inserted
within the U-shaped drape between the slabs. The impermeability and
flexibility of the drape, coupled with the insulating property of
the mat provide an inexpensive, effective fire seal between
building panels that can also accommodate seismic displacement.
Inventors: |
Barr, Roger; (Williamsport,
PA) |
Correspondence
Address: |
BAKER & BOTTS
30 ROCKEFELLER PLAZA
NEW YORK
NY
10112
|
Assignee: |
E.M.E.H., Inc.
Lebanon
NJ
|
Family ID: |
34573315 |
Appl. No.: |
10/701289 |
Filed: |
November 4, 2003 |
Current U.S.
Class: |
52/459 |
Current CPC
Class: |
E04B 1/948 20130101;
E04B 1/6804 20130101; E04B 5/023 20130101 |
Class at
Publication: |
052/459 |
International
Class: |
E04C 003/00 |
Claims
I claim:
1. A fire-barrier expansion joint for insertion between adjacent
building panels comprising: a strip of flexible heat-resistant
impermeable sheet material shaped to form an elongated trough with
a generally U-shaped cross-section, and an elongated mat of
expandable fire-resistant material disposed within said trough.
2. The expansion joint of claim 1 wherein the upper edge of each
side of said trough is bent outwardly at approximately a right
angle to said side.
3. The expansion joint of claim 1 wherein said sheet material is
stainless steel foil.
4. The expansion joint of claim 3 further comprising a layer of
insulating material lining said trough.
5. The expansion joint of claim 1 wherein said mat comprises a
combination of non-combustible fibrous material and heat expandable
particles.
6. The expansion joint of claim 1 wherein said mat disposed within
said trough is under compression.
7. The expansion joint of claim 6 wherein said mat under
compression seals said trough to said adjacent building panels.
8. The expansion joint of claim 6 wherein said mat under
compression holds said expansion joint against said adjacent
building panels.
9. The expansion joint of claim 6 wherein said mat under
compression locks said expansion joint to said adjacent building
panels.
10. The expansion joint of claim 1 wherein said mat disposed within
said trough is configured to remain under compression.
11. The expansion joint of claim 1 wherein said mat disposed within
said trough is configured to remain under compression when the
distance between the adjacent building panels varies up to 50% from
the distance between the adjacent building panels when said mat was
inserted within said trough.
12. A method for inserting a fire-barrier expansion joint between
adjacent building panels comprising: (a) inserting between said
adjacent building panels a strip of flexible heat-resistant
impermeable sheet material shaped to form an elongated trough with
a generally U-shaped cross-section, and (b) inserting an elongated
mat of expandable fire-resistant material within said trough.
13. The method of claim 12, further comprising inserting under
compression said elongated mat of expandable fire-resistant
material within said trough.
14. The method of claim 13, further comprising inserting under
sufficient compression said elongated mat of expandable fire
resistant material within said trough so that said mat remains
under compression when the distance between the adjacent building
panels varies up to 50% from the distance between the adjacent
building panels when said mat was inserted within said trough.
15. The method of claim 13, further comprising inserting under
sufficient compression said elongated mat of expandable fire
resistant material within said trough so that said mat remains
under compression when the distance between the adjacent building
panels varies up to 50% from the distance between the adjacent
building panels when said mat was inserted within said trough and
said trough remains sealed to said adjacent building panels.
16. The method of claim 13, further comprising inserting under
sufficient compression said elongated mat of expandable fire
resistant material within said trough so that said mat remains
under compression when the distance between the adjacent building
panels varies up to 50% from the distance between the adjacent
building panels when said mat was inserted within said trough and
said mat under compression holds said expansion joint against said
adjacent building panels.
17. The method of claim 13, further comprising inserting under
sufficient compression said elongated mat of expandable fire
resistant material within said trough so that said mat remains
under compression when the distance between the adjacent building
panels varies up to 50% from the distance between the adjacent
building panels when said mat was inserted within said trough and
said mat under compression locks said expansion joint to said
adjacent building panels.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to expansion joints
for building panels and more particularly to expansion joints for
building panels such as concrete floor slabs that provide the
necessary flexibility for expansion and contraction and at the same
time, block fire and heat flow between adjacent panels.
BACKGROUND OF THE INVENTION
[0002] It is generally understood that in building construction, it
is necessary to provide expansion joints between abutting floor or
wall panels to allow for expansion and contraction of the material
under varying temperatures. In concrete construction, such joints
typically comprise a strip of a relatively soft material interposed
between the edges of abutting slabs of concrete when poured. Over
time, the joint material tends to dry out and pull away from the
opposed concrete surfaces. While this effect poses little problem
in concrete slabs poured on grade, it is a matter of significant
concern when the slabs constitute the floors of a multilevel
structure. Not only would the joint material tend to separate from
the slabs over time, it could even fall out completely during
periods of extreme contraction. In either event, this would leave
gaps between adjacent slabs that would act as chimneys in the event
of a fire in the structure, thereby enabling the fire to rapidly
spread to upper levels.
[0003] In one known form of expansion joint, described in U.S. Pat.
No. 4,756,945, a blanket of non-combustible, heat-expansible
material is folded over on itself to form a barrier strip and
inserted between adjacent building panels. The strip, comprising
inter alia, a combination of non-combustible fibrous material and
heat expandable particles, is secured between the panels by backer
rods pressed in on either side of the strip. Elastomeric sealing
material is then added to cover the backer rods.
[0004] While the material described in the above-mentioned patent,
manufactured and sold by Backer Rod Manufacturing, Inc. of Denver,
Colo., under the name Ultra Block, has suitable heat-resistance and
expansion characteristics for building applications, the manner
disclosed in the patent for securing the material between building
panels is relatively complex and suffers the disadvantage that the
sealing rods and elastomer used to retain the material in place are
subject to drying over time and dropping out.
[0005] In another type of expansion joint, manufactured by the
Watson Bowman Acme Corp. of Amherst, N.Y. and marketed under the
names Wabo Fire Flex and Wabo Flame Guard, heat-resistant material
is formed into a U-shaped trough and secured between adjacent
panels by sheet metal strips along the edges of each leg of the U.
The material is otherwise unsupported or protected against
accidental damage. A similar fire barrier is manufactured by MM
Systems and sold under the name PYRO-FLEX.
SUMMARY OF THE INVENTION
[0006] The object of the present invention is to provide a
fire-resistant joint for building construction that overcomes the
disadvantages of prior art expedients.
[0007] In accordance with the invention, this object is achieved
with a two-piece joint system comprising a strip of fire-resistant,
flexible sheet material formed into a U-shaped trough or drape and
an elongated mat of expandable fire-resistant mat retained within
the drape. The edges of the flexible drape are bent outwardly to
overlay the surfaces of the adjacent building panels and secured
thereto by suitable fasteners. Little or no adhesives and no
sealants are required to secure the joint in place and the
impervious nature of the drape guards against the chimney effect.
The savings in installation time and cost of the invention provides
a further significant advantage over prior art systems.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The foregoing objects, features and advantages of the
invention will become apparent from the following detailed
description thereof, taken in conjunction with the appended
drawings, in which:
[0009] FIG. 1 is a pictorial representation, partially cut away,
illustrating the installation of the expansion joint of the
invention between adjacent building panels;
[0010] FIG. 2 is a cross-section taken along the lines 2-2 of FIG.
1;
[0011] FIGS. 3A, B and C are cross-sectional views similar to FIG.
2 showing the expansion joint as installed, under compression and
when expanded, respectively; and
[0012] FIG. 4 is a cross-sectional view, similar to FIG. 2, showing
a modification of the expansion joint of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0013] Referring now to the drawings, FIGS. 1 and 2 illustrate the
novel expansion joint of the invention as installed between
adjacent building panels of a structure. In this example, the
building panels are shown as adjacent horizontal concrete slabs 12,
14 forming part of a floor of a structure, but it will be
understood that the invention is applicable to adjacent vertical
wall panels as well.
[0014] The joint structure 10 comprises a heat shield or drape 16
made of 2 mil (0.002 inch) thick impermeable stainless steel foil,
formed into a longitudinally extending generally U-shaped trough,
the opposite legs of which are indicated at 18 and 20. The legs 18,
20 are bent along their longitudinal edges at 90.degree. to form
flanges 18a and 20a. The drape 16 can be either metallic or woven
ceramic. The drape 16 can also be woven from fire retardant fabric
and should be flexible. When installed between slabs 12 and 14, the
flanges overlay the upper surfaces of the adjacent slabs and bolts
or other fasteners 22 secure the drape to the slabs. These
fasteners may also serve to secure rails of a raised floor system
installed over the slabs.
[0015] Between legs 18 and 20 of the U-shaped drape 16 is inserted
an elongated mat 24 of expandable fire resistant material, such as
the Ultra Block discussed above. The material is compressible at
nominal (room) temperatures and is partially compressed when
inserted between the legs 18, 20 of the drape, as shown in FIG. 3A.
This permits the mat to be compressed when the adjacent slabs 12,
14 expand at elevated temperatures, as shown in FIG. 3B, and to
expand at cooler temperatures, as seen in FIG. 3C, without
separating from the inner surfaces of legs 18, 20. No sealants or
other inserts are required to maintain the joint structure between
the slabs. The material is inherently resilient and, when installed
under compression, will successfully cycle plus or minus 50% or
more of the nominal joint width. This compression feature also
serves to hold the legs 18, 20 tight against the concrete slabs 12
and 14, which in effect prevents hot gases from breaching the
system.
[0016] As seen in the drawings, a space is left between the bottom
of mat 24 and the curved bottom of drape 16. This allows the drape
to flex without impediment during expansion and contraction of the
joint. A small amount of adhesive may be applied to secure the mat
to the drape after the mat is inserted.
[0017] The stainless steel foil drape 16 is impermeable to gases
and thus forms an impenetrable fire and smoke barrier between the
adjacent slabs. This prevents the occurrence of the so-called
chimney effect, which would otherwise enable heat and fire to rise
up through the floor and enter the space above the slabs. This
increases the fire rating and safety of the structure and aids in
compliance with Underwriters Laboratory standards.
[0018] It will be seen that the expansion joint of the invention is
readily adaptable to different slab thicknesses and separation,
because of the flexibility of the foil drape and the
compressibility of the mat material. Moreover, the joint is
assembled and installed on site, with minimal off-site preparation
required.
[0019] Where the nominal separation between slabs is greater than 3
inches, it may be desirable to supplement the stiffness and fire
resistance of the drape. This may be accomplished, as illustrated
in FIG. 4, by adding a liner 28 to the inside surface of the drape.
Liner 28 may be made of a flexible insulating material inserted
within the drape 16 before insertion of mat 24. Liner 28 may be
made of ceramic fiber blanket, for example, or other flexible
insulation materials, and may be thicker along the bottom of drape
16 than between the legs 18, 20 and mat 24, as shown in FIG. 4.
[0020] Although the invention has been described above as applied
to horizontal concrete slabs in a building structure, it will be
apparent that it has equal utility between vertical wall panels of
a building, whether such panels are concrete slabs or
wallboard-covered framing.
[0021] Moreover, while the heat and fire resistance characteristics
of the inventions have been discussed above, it will be realized
that the enhanced flexibility of the inventive expansion joint
enables it to retain its integrity when the adjacent panels are
moved as a result of seismic activity, as well. This is yet another
advantage of the invention not found in prior art devices.
[0022] Although the invention has been described above in
connection with its preferred embodiments, it will be appreciated
that other embodiments and variations of the invention will occur
to those skilled in the art. Accordingly, it is understood that the
scope of the invention is to be limited only as set forth in the
appended claims.
* * * * *