Improvements in the Construction of Ceilings and Walls for Buildings and other Structures.
Year: 1899

page_text: Date of Application, 16th Nov., 1899-Accepted, 16th Dec., 1899
CALL 1
Improvements in the Construction of Ceilings and Walls for Buildings
and other Structures.
I, FRANZ KEMNITZ, of 9, Bayreutherstrasse, Berlin, W., Germany, Architect, 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:
This invention relates to the construction of ceilings and walls for buildings
and other structures and consists,-for the purpose of the construction of such
ceilings and walls-in a new method of arranging and stretching ropes intended
for supporting the mortar. This purpose is attained by placing or securing cramps
(hooks, clasps, eyes and the like,) to which the ropes are to be fastened, into the
walling of the room to be covered, respectively round the flanges of the parallel
girders or round the rails or respective beams. The ropes are then arranged
netlike between these cramps, the ends of the ropes being tightened as much as
possible. At last, the ends of the ropes are knotted together or otherwise fastened.
The whole net-work gets by this treatment such a considerable tension equally
great in all its parts that the net-work is for usual cases strong enough without
further precautions. The mortar (beton, lime-mortar, pumice-beton or any other
hardening artificial stone-material) is then brought upon the thus prepared net-
work, whereby-if ceilings are to be made-preferably a removable boarding is
arranged underneath the net-work, the boarding being removed after the stone-
material has hardened. If, in any case, the use of such a boarding is not suitable,
a narrow-meshed wire-work is laid upon the net-work, a mortar mingled with
cow-hair, glue and gypsum being then spread upon it, and the beton being applied
after the mortar has hardened."
The invention also consists in giving to the said stretched net-work-if very
strong ceilings, or very resisting walls are to be made,--a greater tension than is
possible by simply tightening the ropes. This purpose is attained by catching
always two parts neighbouring or crossing each other of the net-work with a nail
or a strong wire or the like and twisting or screwing them together, whereby the
tension of the network may be increased as much as may be required. In order
to prevent the tension thus obtained from being lost again, the nail or other
instrument is secured in a suitable way after the screwing has been finished.
Then, the wire-work-if used-and at last the beton, or other hardening artificial
stone-material is applied.
The invention also consists in increasing the tension of the said net-work by
arranging a second net-work supported on points underneath the first net-work, laid
partly across the latter and then tightened, whereby a tighter stretching of the
net-work is secured.
The accompanying drawings serve for the better explanation of the above, and
show, by way of example, the application of the invention to the construction of
ceilings.
Figure, 1, represents a sectional elevation of a beton ceiling;
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anal alavation of nurther form of cuah
coiling

page_text: Fig. 3, represents a sectional plan showing the arrangement of the girders, and
a network formed of ropes;
Fig. 4, represents a sectional plan showing the manner of stretching out the
network and the fastening of the stretching instrument in the boarding;
Fig. 5, represents a sectional elevation through A-B, Fig. 4;
Fig. 6, represents a sectional elevation of another form of a ceiling constructed
according to this invention;
Fig. 7, represents a perspective view of the net-work of this ceiling;"
Fig. 8, represents a sectional elevation of another form of a ceiling constructed
according to this invention;
Fig. 9, represents a sectional plan showing the arrangement of the girders
and a net-work stretched in a peculiar way:
-
Figs. 10, 11, and 12, represent details.
The ceiling shown in Fig. 1, is constructed in the following way:
At first, the cramps (b, b, b, etc.,) ending in a hook (b) or a completely formed
eye are placed round the upper flanges (a) of the parallel I-girders (a), and are
preferably so arranged that they are equally distant from each other and are in
opposite pairs (61, and 2; 63, and 64;) always being situated in a plane at right
angles to the length of the girder (a). After all the cramps (61, 62, 63, etc.,) have
been so arranged and have been suitably fastened in their places for instance by
being hammered, the net-work adapted to serve as the support of the beton is
This net-work consists of two ropes (c) and (d), which, as shown
in Fig. 3 are stretched crosswise between the relative cramps (b1, b2, 63, etc.,) and
are suitable fastened at the ends, after having received a very considerable first
tension by tightly stretching their ends. This first tension is of great practical
importance, because the bearing capacity of the finished ceiling is especially
dependent upon the first tension.
constructed.
The tightly stretched network consisting of the ropes (c) and (d) is then, in
any suitable way, enclosed in a hardening artificial stone material (e), that is,
beton or a similar cement-composition. Also pumice beton and similar mixtures
may as already mentioned-be used, but only for ceilings of which a less bearing
capacity is required.
As also already mentioned, a narrow-meshed wire-work may be used instead of
the boarding, a mortar mingled with cowhair, glue and gypsum being spread upon
it, and the beton being applied after the mortar has hardened. But also, if a
boarding is used, such a wire-work may still be employed, with the intention of
stiffening the body of the beton. After the beton or the mixture used in its
stead has hardened, the boarding--if such an arrangement was used--is removed.
The material of the ropes (c) and (d) is preferably steel-wire, because steel-wire,
tightly stretched, does not extend any more, but, in some cases, wrought iron wire,
though less advantageous, may be used for the said purpose.
In regard to the construction and forming of the net-work, it is to be mentioned,
that, if also in the construction of the ceiling described above (Fig. 1,) the
ropes (c) and (d) have been drawn crosswise and slopingly from one girder to the
other, and then again slopingly to the first girder, and so on, yet it is evident
that also other shapes of the net-work may be used, and, to this end, the ropes
may be drawn in any suitable manner between the girder. Also, the number of
the ropes may be varied; one rope is sufficient; but, two three, four or more ropes
may be used.
The form of construction in Fig. 2 does not substantially differ from the form
described above. The hooks (b) holding the net-work are, in this case, bent round
the lower flanges and are therefore shaped somewhat differently from the
cramps (61, 62, 63 etc.,).
The form of construction in Fig. 9, shows the use of only one single rope (c).
The adjacent cramps (for instance 61, 62, 65, 67;) are stiffly connected with each
other by two crossed stay irons (f), which keep the cramps in their places as
required.

page_text: As already explained above, the first tension of the net-work obtained by tight-
ening the ends of the ropes forming the net-work, does not suffice in all cases,
as, for instance, in the construction of ceilings of relatively very considerable
bearing capacity or where the spaces of tension of the area of the ceiling are very
considerable.
.
A simple method of rendering the tension of the rope net-work sufficient for
such uses, is shown in Fig. 4, a nail (g) of necessary strength and length is put
into each crossing place (h) of two ropes (c) and (d) and then by twisting around
or screwing the nail the tension of these ropes may be increased. In order to
permanently maintain the increased tension thus obtained, the nail (g) may be
driven into the boarding (i), placed as shown in Fig. 5.
Another method of increasing the first tension of the net-work is represented
in Figs. 6, 7, and 8. The cramps (k) used in this case have two parallel side-pieces
and form a bow (2) and a bend (³). The parallel side-pieces of these cramps
are slid over the girders, the protruding ends of the cramps being bent round
the flanges of the girders. Thereby, these cramps are fastened to the girders.
After all the cramps have been affixed, a rope (c) or several such ropes is or are
stretched out in a zigzag way, the rope or ropes being laid into the bows ().
The ends of this rope or of these ropes are tightened and suitably fastened.
end of a rope (1) having been attached to the bend (3) of the first cramp, this
rope () is wound over the nearest part of the rope (c) and passed to the bend of
the opposite cramp (k), drawn through this bend, then again wound over the
nearest part of the rope (e) and so on. At last, the rope (/) is perfectly tightened,
the tension of the rope (c) being thus obtained at the same time, and the free
end of the rope (1) is well fastened.
One
In the above, only constructions of ceilings supported by I-girders have been
described; but it is evident, without any further consideration, that also girders
of another sectional shape, for instance 1-girders, U-irons or rails and the like
may be used for the said purpose. Likewise, instead of these girders, wooden
beams or joists may be employed, the ends of the hooks and cramps being then
bent round or driven into the beams as shown in Figs. 10, 11, and 12. As already
has been mentioned in the beginning, the cramps, hooks, clasps &c., may also
be inserted directly into the walling. It is also evident without further con-
sideration that other shapes of cramps hooks and clasps then those shown in the
Irawings may be employed for the purpose of the invention.
:
About the ceilings constructed according to this invention, the following is to
be mentioned: As of first importance, their production is exceedingly simple and
also cheap for, though the cost of the steel and iron-ropes is somewhat higher
than that of most iron enclosures used hitherto for the production of ceilings, vet
the difference of such cost is not very considerable, and for that an advantage not
to be undervalued is obtained by the quicker and easier production of the ceilings.
The most important advantage of the new ceilings is that the thickness of
material of the ceilings may be relatively small even if a great bearing capacity
is required. Really strong beton ceilings of so small a thickness of material have
not yet been known.
Finally, it may be said that in order to ensure a sufficient first tension of the
steel and iron ropes, mechanical appliances of any suitable kind may be used, for
instance pulleys, winches, levers and other similar pulling instruments being
used in such a manner that they exercise a stretching effect only on the ends or
by pulling endwise of the ropes.
Likewise, the said cramps or the like may be fitted with rings or wheels, through
which the ropes are drawn for facilitating their stretching.
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. A method of producing strong ceilings and walls for buildings and other

page_text: structures consisting in stretching out metal ropes and in tightening and fasten-
ing them at their ends, the metal ropes being then enclosed in a hardening arti-
ficial stone material, substantially as described.
2. A method of producing strong ceilings and walls for buildings and other
structures consisting in stretching out metal ropes between cramps, hooks, clasps,
eyes and the like inserted into the walling of the building or structure, and in
tightening and fastening these ropes at their ends, the metal ropes being then
enclosed in a hardening artificial stone material, substantially as described.
3. A method of producing strong ceilings and walls for buildings and other
structures consisting in fitting girders, rails, beams or-the like with cramps, hooks,
clasps, eyes or the like, in stretching out metal ropes between these cramps,
hooks, clasps eyes or the like, and in tightening and fastening the ropes at their
ends, the thus formed metallic framework being then enclosed in a hardening
artificial stone material, substantially as described.
4. A method of producing strong ceilings and walls for buildings and other
structures, consisting in fitting girders, rails, beams and the like with cramps,
hooks, clasps, eyes and the like, in stretching out metal ropes between these
cramps, hooks clasps, eyes and the like, in tightening and fastening these ropes at
their ends and in twisting or screwing the ropes at their crossing places by means of
a nail or like staff-shaped instrument for increasing the tension of the ropes,
whereupon the nail or staff shaped instrument is fastened, the metallic frame-work
of thus increased tension being then enclosed in a hardening artificial stone
material, substantially as described.
5. A method of producing strong ceilings and walls for buildings and other
structures, consisting in fitting girders, rails, beams and the like with cramps,
hooks, clasps, eyes and the like, in stretching out metal ropes between these
cramps, hooks, clasps, eyes and the like, in tightening and fastening these ropes
at their ends and in twisting or screwing the ropes at their crossing places by
means of a nail or the like for increasing the tension of the ropes, whereupon
the nail is driven into the boarding, the metallic frame-work of thus increased
tension being then enclosed in a hardening artificial stone material, substantially
as described.
6. A method of producing strong ceilings and walls for buildings and other
structures consisting in fitting girders, rails, beams and the like with cramps,
hooks, clasps, eyes and the like, in stretching out metal ropes between these
cramps, hooks, clasps, eyes and the like, in tightening and fastening these ropes
at their ends, and in then, for increasing the tension of the tightened ropes,
affixing underneath them, winding round them and then tightening other ropes,
substantially as described.
DAY, DAVIES & HUNT,
Chartered Patent Agents, 321, High Holborn, London, W.C.,
Agents for the Applicant.