Improvements in or Connected with the Construction of Fireproo Floors and Roofs for Buildings and other Places.
Year: 1889

page_text: Improvements in or Connected with the Construction of Fireproo
Floors and Roofs for Buildings and other Places.
I, CHARLES CARROLL GILMAN of Eldora, Iowa in the United States of America,
Manufacturer of Porous Terra Cotta, 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 :-
My invention relates to improvements in the construction of fire proof floors and
roofs, the beams and rafters whereof are of iron or steel; and it consists in the com-
bination of such a metal frame-work with terra-cotta lumber or porous burned brick
material applied as hereinafter described and claimed.
In the accompanying drawings, which form a part of this specification, Figure 1 is
Figure 2 is an
a perspective view of a fireproof floor embodying my invention.
enlarged detail view of the beam-protecting strip and the means for holding the same
in position. Figure 3 represents a floor as commonly constructed with "voussoir"
blocks of hollow pottery.
The fire-proof floors of iron-framed buildings are at present generally constructed
as illustrated in Figure 3. In such construction the iron I beams A, twelve inches in
depth, are placed five feet apart. The space between the said beams is filled with
"voussoir "blocks of hollow pottery B, bonded together with a stiff mortar of lime or
cement. The upper surface of said blocks is a considerable distance below the upper
surface of said beams, and in this space between the beams is spread a layer of rough
concrete C, as shown in said Figure. To construct such a floor a platform or support
is erected on a level with the under surface of the iron beams to temporarily support
the "voussoir"-blocks, and as these are placed in position they are cemented
together by a thick layer of mortar. The said support or platform must remain
in position until the mortar or cement has hardened which may take from
6 to 10 weeks according to the condition of the atmosphere, for until then
the so-constructed arch cannot maintain itself in position, much less sustain

page_text: a weight thereupon. The "voussoir" blocks owing, to their density, are of
great weight and are good conductors of heat, so that while, such a floor is incom-
bustible, it will, if subjected to great heat, explode or disintegrate, and thus
imperil the whole structure. It will also be noticed that the iron beams are
unprotected on the upper and lower sides, except as protection is afforded by the
floor above and the ceiling of plaster below. (not shewn).
Referring to Figures 1 and 2 of the drawings which illustrate my invention;
D designates the iron beams supported by iron girders. (not shown). Said beams
are of the usual I form in cross section, have a depth of about ten inches and
are placed 5 feet apart from centre to centre. Between said beams I fit what I
designate "joists" of terra cotta lumber or of a porous burned brick material.
Said joists have a depth of 12 inches, or 2 inches in excess of the depth of the
iron beams and are so constructed and arranged as to project one inch above tho
top and the same distance below the bottom flange of said beams. Each joist
consists of three parts, two haunches. F F and a key, H.
The joists may be divided into a greater number of parts; but as the material
thereof can be made in long pieces and can be sawed to effect tight fitting joints,
the division into three parts affording greater strength, is preferred. The ends of
the haunches which abut against the beams are, preferably, given the proper form,
while the material of which they are made is in a plastic state, though this may
be done subsequently to firing, since the material can then be readily worked
with edged tools. The opposite ends of the haunches, as also the opposing ends
of the key, are sawed diagonally to the proper angle after the material has been
burned, so as to insure closely-fitting joints.
The sections composing the joist can be cut or trimmed by the use of edged
tools to the exact size required, and the parts can be duplicated so exactly as to
be interchangeable. The said joists are placed side by side, so as to touch each
other and fill the space between the beams. They can be rapidly placed in position
in the following manner: The haunches are first adjusted to the iron beams, and
their free ends supported by a platform or temporary scaffolding erected from the
floor below. The key is then inserted between the haunches from above and driven
firmly into position by the use of a heavy mallet.
To obviate the tendency of the key to draw or rebound (which occasionally
happens) when being driven to place I preferably apply a very thin layer of lime
mortar or cement or melted asphaltum to the impinging edges thereof.
Owing to slight inaccuracies in the adjustment of the beams, which cannot be
guarded against, it occasionally occurs that the key, after having been driven
firmly into place, will project below the haunches to the extent of about an inch,
(more or less) and in order that the key may not be impeded in its downward
movement the platform supporting the haunches must be so arranged and placed as
not to interfere therewith. The projecting part of the key may subsequently be
trimmed off with an adze.
The blocks composing the sectional joists may be solid or hollow and from three
to six inches in width.
To perfectly fireproof the top and bottom of the iron beams I apply thereto the
bevelled protecting strips 1, which match the bevelled haunches F, and are fastened
thereto by nails K. These protecting strips are about one inch in thickness
formed of the same material as the said joists. A lumber floor may be laid upon,
and nailed to said joists and a ceiling of plaster applied without the use of
laths.
As the terra cotta lumber weighs much less than the "voussoir" blocks of hollow
pottery, iron beams of lighter construction may be employed, and as the said material
is a very bad conductor of heat it is proof against the joint action of fire and water,
and thus completely protects the iron beams from the action of said elements. The
cost of said material and that of erection is considerably less than that of the construc-
tion first described. Such a floor may be profitably erected in cold weather, and is
ready for the application of boards P and plaster M immediately after erection, which

page_text: is a work of carpentry rather than masonry, for its' retention in position is not depen-
dent upon the hardening of mortar joints. The thin film of mortar, which I preferably
employ, does not perform the function of an ordinary mortar joint, as in the floor of
"voussoir "-blocks, but serves to prevent rebound of the key. If it served the function
of a mortar joint it would be necessary to await the hardening of the same before
removing the support, which in practice is not done for the support is generally
removed immediately after the joists are in position.
The construction herein described may also be employed in the construction of roofs
of iron-framed buildings.
The expression or term "terra cotta lumber "as used in the Specification and claims,
is to be understood as including any porous burned-brick material possessing the
qualities herein set forth.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that
what I claim is :-
1. The combination of iron beams with sectional joists of a porous burned brick
material, said joists consisting of three blocks, the opposing edges of which have been
sawed to the proper angle, and are closely fitted together without the intervention of
the ordinary mortar joint substantially as described.
2. The combination of iron beams with sectional joists of a porous burned brick
material, said joists projecting beyond the top and bottom of said beams, and each
joist consisting of three blocks the opposing edges of which have been sawed to the
proper angle, and which blocks are closely fitted together without the intervention of
the ordinary mortar joint, and protecting strips applied to the upper and lower surface
of said beams and secured to said joists substantially as described.
3. The combination of iron beams with blocks of fireproofing material occupying
the space between said beams, said blocks projecting beyond the top and bottom
thereof, and protecting strips applied to the top and bottom of said beams and secured
to said blocks, substantially as described.
4. The combination of iron beams with blocks of fireproofing material occupying
the space between said beams and projecting beyond the top and bottom thereof, and
having bevelled corners adjacent thereto and bevelled protecting strips laid on the top
and bottom of said beams and secured to mid blocks, substantially as described:
5. The combination of iron beams with sectional joists of fireproofing material
supported between the same and projecting beyond the top and bottom thereof, pro-
tecting-strips covering the top and bottom of said beams and secured to said sectional
joists and with a floor applied to the top and a ceiling of plaster to the bottom of said
strips and joists, substantially as described.
1000