Improvements in the Manufacture of Bodies to Serve as Slabs, Planks, Beams, and the like.
Year: 1895

page_text: Date of Application, 13th Apr., 1895
Complete, Specification Left, 10th Jan., 1896-Accepted, 29th Feb., 1896
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Bodies to Serve as Slabs,
Planks, Beams, and the like.
I, PAUL STOLTE, of Genthin, in the German Empire, Manufacturer, do hereby
declare the nature of this invention to be as follows:-
Hitherto it has been the practice in manufacturing slabs, planks, beams and the
like of cement, plaster of Paris, and such like materials, in which iron bars are
inserted, to embed the latter in the mass at the time this mass is compresse'l or
rammed.
It has been found that such bodies constructed in this manner do not possess the
strength desirable for the purposes for which they are used. Experiments which
have been carried out with such bodies that have been in use have shewn that the
iron bars are surrounded by a large number of spaces and consequently have
rusted. Further investigation has demonstrated that the spaces are caused more
especially through small stones which in the process of ramming become wedged
against the surface of the bars and prevent the cement making a good contact at
all points with the iron bars. Further, during the ramming or compression, the
bars are subjected to violent shocks and are even often bent, particularly in the
case of flat bars. The bar seeks to recover its original form and, even though this
tendency of the bar is slight, it is yet sufficient to loosen the bar from the cement
when setting and to cause the formation of spaces or holes on the underside of the
slab, plank or beam.
According to my invention the slab, plank or beam is first prepared by powerfully
ramming, beating or compressing the cement without the insertion of iron bars.
The bars are then carefully pressed on edge from above into the mass and the
spaces left above the bars filled with fluid cement. By this operation the cement
next the bars is still further compressed so that the latter come into intimate
contact at every point with the cement without being subjected to any tension.
To effect a still more intimate contact V-shaped channels are formed in the
upper part of the compressed bodies, which channels extend to the spaces which
the bars are intended to occupy. The channels are then about half filled with
fluid cement, soluble glass, or other suitable material which unites easily and
intimately with iron and cement. The iron bars are then sunk through these
masses which are still in the fluid condition into the slabs, planks or beams to the
necessary depth whereby they become thoroughly wetted before they reach the
compressed cement so that practically all, even the smallest, pores are filled and
the formation of holes or spaces is avoided. Rusting is in this manner excluded
and the resulting slabs, pianks or other bodies will support heavy loads without
breaking.
In manufacturing my cement slabs, planks, beams or the like I employ a mould
the ends of which are preferably inclined to the back and front so that the
resulting bodies will have the form of a parallelogram. Cement or concrete is
then compressed or rammed into this mould for forming solid slabs, planks or
beams whereby, if hollow beams are required, rods or bars are arranged in the
mould and care must be taken that the cement is thoroughly compressed beneath
these rods or bars. When the mould is filled and the mass smoothed on the top,
channels are formed in the wet mass preferably by means of a toothed fillet or
scraper shaped to correspond with the desired shape of the channels.
The flat iron strengthening rods are then inserted preferably by means of fork-
shaped carriers which, if desired, may be provided with handles, and into the slits

page_text: of which the flat iron bars are inserted. Instead of forming channels in the slab,
plank or beam after it has been formed, the said channels may be formed during
construction.
When the bars are inserted the channels or grooves may be filled with concrete
or cement and the whole mass may be compressed or beaten together from above.
In this last named beating process the iron bars receive no damage as they are
perfectly immovably embedded in solidly compressed cement. Only the cement
on the top which has just been filled in is hereby compressed so that it forms a
solid mass with the cement compressed or rammed before the bars are inserted.
Dated this 29th day of January 1895.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Bodies to Serve as Slabs,
Planks, Beams, and the like.
I, PAUL STOLTE, of Genthin, in the German Empire, Manufacturer, 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 :-
Hitherto it has been the practice in manufacturing slabs, planks, beams and the
like of cement, plaster of Paris, and such like materials, in which iron bars are
inserted, to embed the latter in the mass at the time this mass is compressed or
rammed.
It has been found that such bodies constructed in this manner do not possess the
strength desirable for the purposes for which they are used. Experiments which have
been carried out with such bodies that have been in use have shewn that the iron
bars are surrounded by a large number of spaces and consequently have rusted.
Further investigation has demonstrated that the spaces are caused more especially
through small stones which in the process of ramming become wedged against the
surface of the bars and prevent the cement making a good contact at all points
with the iron bars. Further, during the ramming, or compression, the bars are
subjected to violent shocks and are even often bent, particularly in the case of flat
bars. The bar seeks to recover its original form and, even though this tendency
of the bar is slight, it is yet sufficient to loosen the bar from the cement when
setting and to cause the formation of spaces or holes on the underside of the slab,
plank or beam.
According to my invention the slab, plank or beam is first prepared by
powerfully ramming, beating or compressing the cement without the insertion of
iron bars. The bars are then carefully pressed on edge from above into the mass
and the spaces left above the bars filled with fluid cement. By this operation the
cement next the bars is still further compressed so that the latter come into
intimate contact at every point with the cement without being subjected to any
tension.
To effect a still more intimate contact V-shaped channels are formed in the
upper part of the compressed bodies, which channels extend to the spaces which
the bars are intended to occupy. The channels are then about half filled with
fluid cement, soluble glass, or other suitable material as shewn at which unites
easily and intimately with iron and cement. The iron bars are then sunk through
these masses which are still in the fluid condition into the slabs, planks or beams to
the necessary depth whereby they become thoroughly wetted before they reach
the compressed cement so that practically all, even the smallest pores, are filled
and the formation of holes or spaces is avoided. Rusting is in this manner

page_text: excluded and the resulting slabs, planks or other bodies will support heavy loads
without breaking.
To enable my invention to be fully understood I will describe it by reference to
the accompanying drawing, in which :-
Figure 1 is a plan of a mould for manufacturing slabs and the like according to
my invention :
Figure 2 is a transverse section of a mould containing cement :
Figure 3 is an elevation of the toothed scraper hereinafter described:
Figure 4 is a transverse section of a mould containing a slab :
Figures 5, 5 and 5 are elevations of three forms of carrier hereinafter
described.
In manufacturing my cement slabs, planks, beams or the like I employ a mould
the ends b, b of which are preferably inclined to the back and front a, a so that the
resulting bodies will have the form of a parallelogram. Cement or concrete d is
then compressed or rammed into this mould for forming solid slabs, planks or
beams whereby, if hollow beams are required, rods or bars c are arranged in the
mould to form the hollow portions and care must be taken that the cement is
thoroughly compressed beneath these rods or bars. When the mould is filled and
the mass smoothed on the top, channels are formed in the wet mass preferably
by means of a fillet or scraper i having teeth k and being shaped to correspond
with the desired shape of the channels.
The flat iron strengthening rods e are then inserted preferably by means of fork-
shaped carriers m which, if desired, may be provided with handles m' and into
the slits n of which the flat iron bars are inserted. Instead of forming channels
in the slab, plank or beam after it has been formed, the said channels may be
formed during construction.
When the bars e are inserted, the channels or grooves kl may be filled with
concrete or cement and the whole mass may be compressed or beaten together from
above. In this last named beating process the iron bars receive no damage as they
are perfectly immovably embedded in solidly compressed cement. Only the
cement on the top which has just been filled in is hereby compressed so that it
forms a solid mass with the cement compressed or rammed before the bars are
inserted.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A process for the manufacture of slabs, planks, beams and the like of beton
or the like having bars or rods embedded therein, such process consisting in first
ramming or compressing the said beton or the like into a suitable mould and in
then inserting the bars or rods into the soft mass before it sets substantially as
described.
2. A method of carrying out the process described in Claim 1 wherein channels
are formed in the beton or the like after it has been rammed or compressed in the
mould, the said channels being filled with a fluid material, capable of hardening
and of uniting with iron and cement before the bars or rods are inserted
substantially as, and for the purpose, herein before described.
3. In a process of the kind described, the use of fork-shaped carriers for
inserting the iron bars into the cement, substantially as described.
4. The improved slabs, planks and beams hereinbefore described and illustrated
in the drawing.
Dated this 10th day of January 1896.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.