Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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1~64725
~ he present invention relates to a device usable for casting concre_
-te Æ faceæ or the like. Wi-th a view to make flat concrete surfaces it is knownto use casting rulers arranged so as to form a formwork, shuttering or like
casing or framing into which the concrete is cast, worked or placed. The flat-
ness of the visible surface is achieved by scraping the top surface of the
concrete.
According to an improvement known in the prior state of the art and
disclosed in the ~rench patent specification N 2,13~,792 in the name of the
same applicant there are used concrete rulePs or like beam-shaped members com-
prising a ridge-like or web-shaped upper portion and a base-like widened lower
portion used as a sacrifice shuttering or formwork and which remain embedded
in the concrete mass after having perfoxmed their function as shuttering ele-
ments or like formwork components.
Such prefabricated elements however suffer from the inconvenience of
being heavy and cu~bersome or bulky. It is difficult and expensive to carry
or convey them to the places of use ; moreoveP their length has been prede-
termined before they are forwarded to the building site thereby involving
difficulties of adapting them to any shapes of ooncrete slabs or like plates.
The objeot of the present invention is to avoid these drawbacks and
for this purpose it provides a ligh~-weight ~3ectional bar or like member the
lower portion of whioh is open ~ h~llow sub~tantially over -the full length
of said sectional bar~
According to another essential characterizing feature of the inven-
tion ~uch light-weight sectional bars are reinforced or strengthened and sta-
bilized by casting concrete or any other settable or hardenable material into
the inside of the open or hollow lower portions of su¢h ~ectional bars. Such
~` a reinforcing enables to aohie~e a good resistance to the pushing forces or
thrust of the concrete when casting the slab. On account of such a filling
the very strong side forces due to the weight of the concrete slabs pressing
or bearing from the outside against the ruler are ea~ily ~ustained.
Accordihg to the invention the users only have to carry or convey
the light-weight sectional members made for instance from plastics material
since concrete is available on the working site.
The deliveries may therefore be accomplished over inter~ational ai8-
tances without substantially burden or encumber the cost prices. In addition
the material used is strong, of light weight, practical and economical.
It does not get ru~ty and wears away at the same time as the slab
is wearing away while retaining the init~al appearance of the latter ; in
addition it makes the use of stripping or releasing oils quite useless as
said sectional bars are adapted to remain or be left embedded within the mass
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Jr body of the concrete slab.
It is moreover possible to make concrete slabs of any de-
sired size by placing these rulers suitably. The junction between
any two sectional bars at a given angle may be carried out perfect-
ly by sawing the plastic shells or members to the desired lengths.
Any special lengths needed may be obtained on the building site ac-
cording to requirements by sawing on the spot.
These purposes and objects are satisfied by the present
invention which specifically relates to a light-weight elongated
sectional member of generally Y-shaped cross-section for use as a
levelling aid and expansion joint and which is embedded during the
casting of paving surfaces, the sectional member being of inverted
Y-shape when in use and comprising a thin web having an upper edge
which provides a levelling edge, and two downwardly diverging legs,
the legs having along their lower edges outwardly extending longi-
tudinal flanges upon which the member stands, and at least one long-
itudinal rib extending along the inner surface of each leg, the
sectional member being of non-metallic substantially inelastic mat-
erial to retain its sectional shape during casting and use and its
upper edge flush with the paving surfaces.
The invention also discloses a method of casting concrete
surfaces, comprising the steps of using the above sectional members
and casting a reinforcing concrete between the legs before employing
said reinforced sectional members as concrete sectional members.
The invention will be better understood and further char-
acterizing features, details and advantages thereof will appear more
clearly as the following explanatory description proceeds with refer-
ence to the accompanying diagrammatic drawings given by way of non-
limiting examples only illustrating several specific presently pre-
- 30 ferred forms of embodiment of the invention and wherein:
Figure 1 shows a perspective view of a cross-section through
a light-weight sectional member or bar forming a casting ruler ac-
cording to the invention;
Figure 2 shows a perspective view of a shuttering or like
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formwork made by assembling rulers extending at right angles toeach other; and
Figure 3 shows a cross-section through another form of
embodiment of the invention wherein a double parallel sectional
shape has been adapted to the sectional bars.
According to the form of embodiment shown in Figure 1,
a sectional member or bar 1 exhibits a thin upper web or ridge 2
which is thicker than the sidewaIls3, 4 of the hollow lower part,
which hollow part 5 comprises on its inner faces projecting ribs 6
with tenons or lugs 7 or other protrusions; bearing flanges or
footings or like bases 8 and 9 are provided at the bottom slightly
at angles opening outwards. On the other hand a sleeve or bushing
10 is provided substantially at the top and in the axial plane of
said open lower portion of the sectional member.
The aforesaid tenons or lugs are provided so as to
be hooked or anchored within the concrete 11 cast inside as shown
more clearly in Figure 2. They perfectly cling to the concrete
as the latter contracts or tightens upon drying or setting; the
; bearing flanges 8 and 9 will later on facilitate the bedding,
fastening or fixing of the ruler upon being laid; as to the sleeve
or bushing 10 it is adapted to receive a rod (not shown) for
aligning the sectional bars end to end in registering relation-
ship.
The symmetrical shape of the ruler which is an isosceles
triangle in the case of Figure 1 enables a uniform shinkage of
t,he filling concrete clinging to or gripping the inside faces of
the hollow part of the sectional bar thereby avoiding any possible
bending or deflexion of this
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sectional member. Moreover as the outer edges of the ruler are smooth they do
not adhere to the slab concrete more especially as when eaid ruler is advan-
tageously extruded from a plastics material of suitable grade or quality. ~he
shri~cage of the concrete of such slabs will take place straig~ forwardly and
avoid cracks outside of these areas. Owing to the steep or very sloping shapes
of the legs or faces 3,4 of the sectional bars only a small portion of the slab
iB supported by the sectional bar. When using such sectional members it is pos-
sible to replace reinforced concrete elements having a certain width by others
which are narrower without reduoing the strength characteristics of the slabs
1~ thereby enabling to significantly reduce the weight and accordingly the cost
price of the construction.
On the other hand a substantial technical ad~antage of tne sectional
members according to the invention is the thinnees or narrowness of the upper ;
ridge or web (a few millimeters) which will be practically invisible once the
flagging, paving or flooring has been formed. It is possible to use this ruler
for flaggings, pavings, or like slabbings which have been increased in hardness
(chafing or wearing layer) by incorporating carborundum therèin for instance.
The sectiOnal member according to the present invention is of course
; ~ not at all limited to the for~ of embodiment shown in ~i F e 1. In particular
the shape of the upper ridge or web may be straight, curved or bulging, tape-
ring or conical, Z-shaped or hollow ; the tenons or lugs of the inner face of
the hollow portion may be provided in a number proportional to -the height of
the ruler ; the assembling or connecting device may be provided at the ends
`~ of the sectional member as well as throughout the length thereof ; it may
differ ~rom the de~ice shown in ~igure 1 or be positioned at any other loca-
tion of the hollow portion. This aforesaid hollow portion may al~o have a
~hape differing from that of an i~osceles triangle or ~ctangle.
Moreover this hollow portion may if desired be closed rather than
opening downwards as previously described.
~ igure 2 illustrates a shuttaring, formwor~ or like casing or fra-
ming made from sectional members according to the present invention in the
case of forming rectangular concrete slabs. Once these light-weight sectional
members have been prepared or made to the desired lengths, stiffened or rein-
forced with filling concrete they are accurately aligned by means of the
assembling or joining devioes mentioned hereinabove. ~he sectional cross-
members joining two lines or ro~ls of sectional bars are prepared by suitable
sawing after ha~ing previously broken off that part of the filling concrete
which is likaly to impede the sawing step. Moreover they are advantageously
sealed or fixed in position before casting the slabs by means of anchoring
joints 18, 19 embedding one portion of the seatings or bearing flanges or
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footingæ 8, 9 of the rulers 1.
Pigure 3 shows another form of em ~diment of casting ~lers
according to the invention compriæing a second substantially flat sectional
member 12 extending in parallel relation to a side face of the first sectlona
member, the s~ace left bet~een this new sectional member and the side face or
wall of the first sectional member being filled with a flexible or yielding
packing material 13 such as polystyrene or neoprene for instance. ~his second
sectional member 12 is secured to~the first sectional member 1 by means of ribs
or tenons 14, 15 which co-operate with the oppositely lying outwards projecting
ridge or flange 9 of the sectional bar 1.
~ he additional provision of the flexible or yielding interme-
diate packing 13 enables to obtain a ruler adapted to absorb stresses upon the
expansions of any two con'fronting concrete slabs 16, 17. The shape of the in-
~e~mediate æpace or gap provided at an open angle prevents the soft packing
w*ichils located therein from being lifted or raised.
, At 18', 19~i are shown fixing or sealing joints for the sec-
tional rulers,1, 12 similar to the sealings or the fixings 18, 19 seen in ~i-
gure 2.
It i~ also posisible to i~void the additional provision of the
' 20 ~ soft packing 13 of the kind described~3;,for this purpose the sectional member
` 12 may exhibl~ resilient thin or fine ribs connecting it at evenly spaced,interval8 throughout its hei~ht to the outside faoe of the first sectional
mèmber.-
he present invention is of course not'at all limited to the
orms of embodiment described~which ha~e been disclosed by way of example only.
~ In particular, it oomprise ,all the means constituting techni~l equivalents
,~ ~ 'of the~means desc~ibed aa well as their combinations if same are carried out
~ aooording to its gist and used wlthin the sc~pe of the appended olaim8.
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