Note: Descriptions are shown in the official language in which they were submitted.
2146216
1
TITLE OF THE INVENTION:
Process for making fibre reinforced cellular cementious
building materials
NAME OF INVENTOR:
Ramsay S. Bellingham
FIELD OF THE INVENTION
The present invention relates to a process for making
fibre reinforced cellular cementious building materials,
including all main structural components.
BACKGROUND OF THE INVENTION
International Patent Application PCT/F192/00233 published
under the provisions of the Patent Cooperation Treaty March 17,
1994 as International Publication Number WO 94/05605, discloses
a fibre reinforced cellular cementious insulation board. The
advantages of such material are discussed in the application,
namely; light weight, tensile strength along with a thermal
insulation capacity. The manufacturing process is not
disclosed. The resulting product is soft and consequently, is
not capable of being used for structural building components.
The specification of U.K. Patent Application 2,225,599A
published June 6, 1990 discusses a method of producing fibre
reinforced cellular gypsum ceiling tile. A highly foamed
slurry of gypsum material is poured onto a moving conveyor belt
on which is positioned a layer of glass fibre tissue material.
A further layer of glass fibre tissue material is then placed
upon the surface of the slurry and passed beneath a gauging
2146216
2
device which determines the thickness of the resulting board.
The slurry is then allowed to penetrate the layers of fibrous
material before the gypsum material sets. The slurry of
consists of gypsum material mixed with water into which air has
been entrapped with the help of a surfactant foaming or air-
entraining agent. The process employed in the manufacture of
such fibre reinforced cellular building materials has an effect
on the ultimate quality of the building materials produced.
The U.K. Patent Application contains a warning that vibration
of the conveyor belt must be avoided, as it has the undesirable
effect of reducing the degree of foaming of the slurry, thereby
increasing the density of the product . However, in the absence
of vibration there is imperfect penetration of the slurry into
the fibrous tissue.
SUMMARY OF THE INVENTION
What is required is a process for making fibre reinforced
cellular cementious building materials that will produce
building materials capable of being used as structural members .
According to one aspect of the present invention there is
provided a process for making fibre reinforced cellular
cementious building materials. Firstly, mix separately a foam
slurry and a cementious mixture containing water and random
glass fibres. Secondly, combine the foam slurry w~_th the
cementious mixture in a container to form a cellular cementious
slurry containing random glass fibres. The container has a
bottom with an orifice positioned adjacent the bottom. Thirdly,
pull two parallel spaced layers of integrally formed glass
fibre reinforcing mesh through the mixing container filled with
cellular cementious slurry and out through the orifice into a
curing tray. As the reinforcing mesh passes through the mixing
container it pulls along with it cellular cementious slurry.
The orifice restricts the amount of cellular cementious slurry
that is drawn into the curing tray, thereby serving to gauge
2146216
3
the: dimensions of the building material. Fourthly le~xve the
cellular cementious slurry to cure in the curing tray until the
cellular cementious slurry has set thereby resulting in a
cellular cementious building material having two rei~~torcing
layers of integrally formed glass fibre mesh with random glass
fibres extending between the two layers of integrally formed
glass fibre mesh.
With the process, as described above, the random glass
fibres become interconnected with the integrally formed glass
fibre mesh to improve the tensile strength of the resulting
product. Using the described process materials can be
fabricated that will substitute for plywood, drywall, studs,
rafters, beams, siding, shingles, shakes, soffits, doors, and
strapping. The resulting products can be made with suf:Eicient
strength that they are capable of serving as structural
members. There is minimal disturbance during processing so the
cementious slurry remains highly foamed resulting in a unique
combination of light weight and strength. The resulting
building materials can be cut, nailed, and otherwise used as
wood building materials are currently used. The resulting
materials are substantially the same weight as wood and can be
used much like wood, but are fireproof and considerably less
costly. The building materials can be made, using the
described process, out of waste materials such as iJ_y ash,
blast furnace slag, silica fume, gypsum, limestone and broken
glass. These waste materials are mixed with sand, and cement
to form a strong cementious mixture.
According to another aspect of the present invention,
there is provided a building material which includes a cellular
cementious body having at least two layers of integrally formed
glass fibre reinforcing mesh with random glass fibres extending
between the at least two layers of integrally formed glass
fibre reinforcing mesh. It is preferred that zirconium glass
fibres be used.
2146216
4
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the invention will be~.orie more
apparent from the following description in which reierc~nce is
made to the appended drawings, wherein:
FIGURE 1 is a diagrammatic representation of the prorer.r_cc~
process for making fibre reinforced cellular c~:aeentioua
building materials.
FIGURE 2 is cutaway perspective view of a b~cr:.i lda_nc~
material made in accordance with the teachings of the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A process for making fibre reinforced cellular cementious
building materials will now be described with reference to
FIGURES 1 and 2.
Referring to FIGURE l, the ingredients selected to be
included in the cementious mixture are placed in a 'cur_ntable
portioning device 12. As previously described, these
ingredients include random glass reinforcing fibres, sznd and
cement; together with such materials as fly ash, blas-c furnace
slag, silica fume, broken glass, gypsum and limestone. The
chosen mixture of ingredients are delivered on a continuous
basis to first mixer 14. The steps in the process are as
follows: Firstly, mix separately a foam slurry in a second
mixer 16 and a cementious mixture containing water and
zirconium random glass fibres in first mixer 14. Secondly,
combine the foam slurry from second mixer 16 w~_th the
cementious mixture from first mixer 14 in a third mixer 17 to
form a cellular cementious slurry containing random glass
fibres . The contents of third mixer 17 are then discharged
into a container 18. Container 18 has a bottom .20 vaith an
adjustable orifice 22 positioned adjacent bottom 20. Thirdly,
pull two parallel spaced layers of integrally formed ~ ~_r Coil~_11m
CA 02146216 1999-10-15
glass fibre reinforcing mesh 24 and 26 through mixing container
18 filled with cellular cementious slurry and out through
adjustable orifice 22 into a curing tray 28. Reinforcing mesh
24 and 26 are pulled by cables 30 and 32, respectively. Cables
5 30 and 32 depend from an overhead loop cable 34 to pull
reinforcing mesh 24 and 26 slowly to the end of curing tray 28.
Reinforcing mesh 24 and 26 are fed from feed stock rollers 36
and 38, respectively. Reinforcing mesh 24 engages positioning
roller 40 and reinforcing mesh 26 engages a lip 42 of orifice
22 which helps to maintain reinforcing mesh 24 and 26 in
parallel spaced relation. As reinforcing mesh 24 and 26 pass
through mixing container 18 they pull along with it cellular
cementious slurry 44 containing random glass fibres 46 which
tend to engage reinforcing mesh 24 and 26. This process is
referred to as "pultrusion". Orifice 22 restricts the amount
of cellular cementious slurry 44 that is drawn into curing tray
28, thereby serving to gauge the dimensions of the resulting
building material. At least one polishing roller 45 is
preferably positioned downstream of orifice 22. Polishing
roller 45 is also capable of patterning or embossing the
resulting product. Fourthly, leave cellular cementious slurry
44 to cure in curing tray 28 until cellular cementious slurry
44 has set.
Referring to FIGURE 2, the process, as described above,
results in a building material 48 having a cellular cementious
material 44 with two reinforcing layers of integrally formed
glass fibre mesh 24 and 26. Random glass fibres 46 extend
between glass fibre mesh 24 and 26. A portion of random glass
fibres 46 become interconnected with glass fibre mesh 24 and
26 to improve the tensile strength of building material 48.
Referring to FIGURE l, it is preferred that curing tray
28 be equipped with rollers 50 which are positioned on
laterally extending rails 52. When one curing tray is filled
it can be pushed laterally out of the way to cure, and a second
curing tray can be used so the process is disrupted only
214 6216
6
temporarily to switch trays.
The preferred mixture ( apart from water and ~.~r..r v,='zi.c:h
averages 50~ by volume j is blast furnace slag ~0 ~, sar.~cks ~.0° ,
fly ash 10~, portland cement 5~, silica fume 3~, and rvi_r_-co~.~iurn
glass fibres 2~. It is preferred that the cementiour ~n.~_x~~~zre
have a low pH level. Curing trays 28 can be pracU;ic:~y.l7_y ~.ry
length, approximately 100 yards long is preferred. It ~~,=~J_1 ~:~:
appreciated that the size of orifice 22 determines whether flat
boards, or dimension lumber is produced such as 2 x Q., 2 :: 10,
etc. Buildings can be constructed with the c:~c:~wca=ib~.d
materials . In fact, the process described can proctu.ce ~~.:~.1 ~tlm
materials necessary for an entire building constructioxz ~ywer7,
including all structural components. The buildings ar_e buil_~t:
by the usual "framing" techniques employed by c~rt?enters
accustomed to working with wood. The materials can posi-Lioned
in place by screws, nails, and glue and then bonded together
in situ by pouring a very light weight short-fibre reinfox=ced
cellular concrete into empty wall spaces. The ce=i_l.al~.r
concrete not only bonds the building components together, but
also serves as insulation and sound proofing. Buildi.nc~:; ~na~~e
from the described materials are low cost, as they ui~ilize in
large part waste materials, as previously described. The
materials can be specially adapted for their intended purposes
by adding ingredients to the slurry, adding a step to the
process or by subsequent treatment while the product i_s curing
in the curing tray. Such treatments include embossing,
colouring, and surface hardening by trays, paddle whe:ea_s, or
other means.
It will be apparent to one skilled in the arL tha'~
modifications may be made to the illustrated embodiment without
departing from the spirit and scope of the invention as
hereinafter defined in the Claims.
