Improvements in and relating to Fire-proof Floors and Ceilings.
Year: 1894

page_text: Date of Application, 9th Oct., 1894 -Accepted, 10th Nov., 1894'
COMPLETE SPECIFICATION.
Improvements in and relating to Fire-proof Floors and Ceilings.
We, CHARLES ALEXANDER BALPH, Contractor, and ELISHA PIERSON SWIFT
WRIGHT, Manufacturer, Citizens of the United States of America, residing
respectively at 644 South Negley Avenue, in the City of Pittsburgh, and Forest
Street, in the Borough of Avalon, both in the County of Allegheny and State of
Pennsylvania, one of the United States of America, do hereby declare the nature
of this invention, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
Our invention relates to the construction of fire-proof floors and ceilings.
The fire-proof floor most generally in use to-day is the hollow tile floor composed
of either hard or porous tile. The hollow tile floor is dependent on the skill and
care of irresponsible workmen who may or may not, set the arches properly, and
accordingly, the strength of such a floor is often impaired by poor workmanship.
Again, a sudden jarring load may break the key of a flat tile arch and destroy
its bond, the result being a caving in of a section of the floor. Furthermore, the
bollow tile floor is designed to carry certain loads and cannot be graduated to suit
the requirements of particular buildings, the cost of construction being practically
the same whether the floor is to be used for a heavy storage warehouse or for light
office purposes.
The object of our invention is provide a fire-proof floor or ceiling which does not
require the employment of skilled labor in its construction; one which is not only
incombustible in itself, but capable of resisting to the highest degree the effect of
heat, and one that will not disintegrate under the combined action of licat and water;
one which can be speedily constructed and put into service; one that will prevent
the transmission of sound from one storey to another, together with certain other
advantageous qualities which it is not necessary to enumerate here.
Our invention consists, generally stated, in connecting the floor beams at intervals
by means of rods or bars, placing a wire net-work over said bars or rods, and
embedding and covering the bars and wire net-work with a strong cement concrete.
Our invention further comprises certain details of construction and combination of
parts, all of which will be fully hereinafter set forth and claimed.
To enable others skilled in the art to make and use our invention, we will describe
the same more fully, referring to the accompanying drawing, in which
Figure 1 is a cross section of a portion of a floor and ceiling before the applica-
tion of the cement to the floor, and showing the cemented ceiling;
Figure 2 is a perspective view of a section of the floor and ceiling, showing more
clearly the construction before the cement is applied to the ceiling;
Figure 3 is a like view showing the cement in places;
Figure 4 is a longitudinal section at right angles to Figure 1, showing the cement
applied to the ceiling and showing the construction before the cement is applied to
the floor;
Figure 5 is a like view showing the construction before the cement is applied to
the ceiling;
Figure 6 is a view of the finished floor and ceiling, and showing the means of
opening communication between the different air spaces; and
Figure 7 is a view of a modified form of bar.
Like letters indicate like parte in each of the figures.
In Figure 1.of the drawing we have represented a portion of a floor in section,
a designating I-beams arranged at suitable intervals apart and having their ends
supported in the ordinary manner. Fitting over the I-beams are the stirrups b
D

page_text: which straddle said beans and support the bars c, said bars being of length corre-
sponding substantially to the space between the I-beams, extending across from
one beam to another and arranged at suitable intervals according to the load they
are to carry. By the employment of the stirrups the bars are supported without
having to punch holes through the beams to secure the bars thereto by bolts passing
through an angle connection on said bars, thus tending to diminish the strength of
said beams. The bars c are preferably supported on their edges and are formed
with the longitudinal ribs e', which serve to aid in supporting the concrete, as will
more fully hereinafter appear. A wire netting d of suitable mesh is supported by
the bars, where it is found necessary to sustain the body of concrete between said
bars C, said wire netting by passing as indicated over these transverse supporting
bars enabling them to carry a greater load and to be placed at farther distances
apart, though the transversely extending bars c may be employed to support the
concrete without the use of the wire netting if desired, the bars being placed nearer
to each other.
Where a ceiling is desired, tie-rods e are employed to connect the beams a, but
said tie-rods are preferably placed as close as possible to the lower flange of the
beam, instead of in the centre thereof. The tie-rods e are brought to perfect
tension by the nuts e'. A wire netting e³ also passes over the tie-rods e in the same
manner as the wire-netting d above referred to.
beam a.
As the construction of the ceiling is usually the first step, a temporary platform
to support the concrete while it is being laid is first erected. This platform is.
usually termed by the builder "a centering," and we will designate it by that term
throughout the Specification and claims. This centering,, is usually formed of
wood, and is supported by the rods g, said rods.g in turn being supported by the
bolts having the hooked ends h². We prefer to employ pipe for the rods
they are lighter and more easily handled. The bolts are held at their upper ends
within the plates i, said plates being bent to engage one of the flanges of the
The centering is drawn up into position and held securely in place by
means of the nuts on said bolts h, but when it is desired to draw the centering
forward to construct another section of ceiling, by removing the nuts the plates i
can be moved along the beam, while by striking the upper end of said bolts they
can be withdrawn from the concrete from below, and moved forward together with the
centering supported thereby, when said centering is again erected in position as
before. Before drawing up the centering to position, however, the bottom faces of
the lower flanges of the beams are protected by strips of asbestos, or like.
incombustible material. The edges of the asbestos strips are turned up
slightly. so that when the concrete is packed the edges will be embedded therein
and the asbestos securely held in place flush with the ceiling. The centering having
been drawn up to position and the wire netting having been passed over the tie-rods.
a concrete such as Portland cement and crushed furnace slag of the proper
consistency, is thrown upon the wire-netting and then packed down through the
said netting onto the centering which gives the concrete a smooth even surface..
The concrete is laid on thick enough to embed the tie-rods.e. As the ingredients
which compose the concrete are the products of the most intense heat, the result is
a thoroughly fire-proof and non-conduction ceiling, which is entirely independent of
the floor. The wire-netting e² sustains and imparts tensile strength to the concrete,
and transmits the weight to the tie-rods e, while the asbestos under the beams a
furnishes a thorough protection from heat where most needed.
e,
n
In constructing the Hoor, a centering & is employed, said centering being supported
in the same manner as the centering, namely, by the use of bolts which
support the rods m, said bolts being secured to plates n by nuts o.
The plates
engage the upper flange of the beans a in the same manner as the plates 7.
centering is provided with the sides so that when said centering
The
is in position
a space will be left between the web of the beams a and the sides for the reception
of the concrete to protect said beams.
The centering having been arranged at the proper height to give the proper

page_text: thickness to the floor, and the bars e and wire-netting d having been arranged as
above described, a concrete similar to that before described is thrown onto the.
netting and packed down through said netting onto the surface of the centering k,
and at the same time into the space between the sides k¹ of the centering and the
webs of the beams a. Sufficient concrete is employed to completely cover and
embed the barse as well as the top of the beams a. The ribs.c' o the bars c serve
to aid in supporting the concrete, while at the same time they increase the strength
of said burs. The concrete is omitted, however, just around the bolts h and land
the supporting plates i and n to allow for the removal of the nuts thercon and the
loosening of said bolts so that they can be withdrawn from below when the
centering is withdrawn. After the withdrawal of the bolts and the removal of
the plates i, n, the space around said bolts and plates can then be filled up with
concrete uniformly with the rest of the floor.
The steel bars e transmit their load to the beams by means of the stirrups b and
practically take the place of small beams, as they are equivalent in carrying power,
the weight of the flanges being saved, as the concrete takes the place of the
flanges, bracing the bars laterally so that the full carrying power of the web is
secured. The bars e are even stronger than the beams are, proportionally, as the
concrete adds a greater strength to the bar than does the flange to a beam, the
bars being embedded in and surrounded by a solid mass, which in time becomes as
stone, and absolutely prevents any tendency to side deflection or buckling.
In Figure 7 we have shown a modified form of the bars for supporting the floor.
This bars instead of having longitudinal ribs thereon, is formed with the projections t
which serve to catch the concrete and support the same. We do not confiue
ourselves to any particular form of projections on the bars, as they may vary as
desired. Any kind of roughened faces ou said bars which will act to catch and
hold the concrete may be employed. If the bars are arranged sufficiently near to
one another the net-work covering may be omitted.
The concrete used for this work is quick-setting, so that the centering can he
moved in a few hours and the next section may then be constructed. The floor
and ceiling are put in by sections, beginning at one wall and building out therefrom
to the opposite wall, but at the last section a light sheet-iron centering is used
which remains permanently in the structure.
The floor is brought up level with the beams a and within the concrete are the
Hoor strips p, in case a wooden floor is.employed. But in case an asphalt, tile, or
cement topping is to be applied the strips p are omitted, while the concrete forms
an excellent base for any such topping of asphalt, tile, or cement.
The space q between the floor and ceiling forms a sound deadening chamber,
while at the same time, by opening communication between the several air spaces,
the air may be circulated throughout the building and may be employed for
ventilating rooms. To form this communication between the air spaces y we
employ the conduits which may be formed of tin or other suitable material, said
conduits extending from one air space up over the beam into the next one, and so
on throughout the building.
The features of advantage to the builder which may be mentioned are these:
The absence of great quantities of tile, which greatly obstruct a building in course
of erection and interfere with the progress of other work. Our floor can be put
up quickly without obstructing the building, and can be used immediately after
construction. It leaves a floor as perfectly level as a cement floor in a cellar. By
having the floor entirely independent from the ceiling a heavy loud carried by the
floor puts uo strain whatever on the ceiling. Any sagging of the Hoor will not
affect the ceiling. Holes can be cut through the floor at any point without
impairing its strength, while at the same time pipes, conduits, etc, can be conducted
through the air spaces between the floor and ceiling without the labor and incon-
venience of embedding them in the floor filling. Furthermore, our construction
tends to tie the building together, the floor being a homogeneous mass, which adds.
strength to the entire structure.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:
1. In a floor or ceiling, the combination with the beams, of metal bars connecting
said beams, an open-work covering extending over said bars, and concrete completely
embedding said barsiand open-work covering, substantially as and' for the purposes
set forth.
2. In a floor or ceiling, the combination with the beams, of metal bars connecting
said beams, said bars being supported by hangers on said beams, an open-work
covering extending over said bars, and concrete completely embedding said bars
and open-work covering, substantially as and for the purposes set forth.
3. In a floor or ceiling, the combination with the beains, of hangers straddling
said beams, metal bars supported thereby, an open-work covering extending over
said bars, and concrete completely embedding said bars and open-work covering,
substantially as and for the purposes set forth.
4. In a floor or ceiling, the combination with the beams, of metal bars connecting
said beams, said bars being supported on their edges, an open-work covering
extending over said bars, and concrete completely embedding said bars and open-
work covering, substantially as and for the purposes set forth.
5. In a floor or ceiling, the combination with the beams, of bars having longitudinal
ribs formed thereon connecting, said beams, said bars being supported on their
edges, an open-work covering extending over said bars, and concrete embedding
said bars and open-work covering, substantially as and for the purposes set forth.
6. In floor or ceiling construction, the combination with the beans, of a centering
suspended therefrom, said centering having side pieces, substantially as and for the
purposes set forth.
7. The combination with the beams, of bars connecting the upper portions of
said beams, an open-work covering extending over said bars, concrete embedding
said bars and open-work covering, bars connecting the lower portions of said
beams, an open-work covering extending over said bars, and concrete embedding
said 'bars and open-work, substantially as and for the purposes set forth.
8. The combination with the main supporting beans, of solid metal supporting
bars of length corresponding substantially to the space between the beams and
extending transversely of and connected to the beams, said bars being supported
on their edges, and a filling of concrete completely surrounding said bars and
supported thereby, substantially as and for the purposes set forth.
9. The combination with the main supporting beams, of solid metal supporting
bars of length corresponding substantially to the space between the beams and
extending transversely of and connected to the beams, said bars being supported
on their edges and having longitudinal ribs on their side faces, and a filling of
concrete completely surrounding said bars supported thereby, substantially as and
for the purposes set forth.
Dated this 9th day of October 1804
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.