[0001] The present invention relates to a metal frame for embodying building structures
made of reinforced concrete.
[0002] A typical configuration of the metal frame substantially provides for a complex of
longitudinal steel rods interconnected by other transversal steel rods. The frame
is normally formed in the building yard by disposing the steel bars in the form according
to the aforesaid configuration and binding them together with iron wire so as to prevent
them from slipping during the reinforced concrete casting.
[0003] As is known, this usual manner of proceeding is somewhat slow and laborious.
[0004] A proposal for remedying this situation is provided by mass producing the frames
outside the building yards with an industrial process, thereafter transporting them
to the building yards and assembling them, ready-for-use, in the related forms.
[0005] The operation of reinforcing the various elements is in this way considerably streamlined,
since the heavy manual work of forming the frames in the building yard is done away
with.
[0006] However, when these pre-formed frames have a markedly spatial configuration, as for
example in the case of those used for girders and pillars, problems arise in connection
with their transportation to the building yard and their handling when laid.
[0007] For, in view of their skeletal structure, their volumetric bulk is relatively much
greater than their weight.
[0008] It is thus requisite to transport, in a certain volume, a weight of steel rods for
reinforcement purposes very considerably less than the weight it is possible to transport
with loose rods for binding in the building yard. In the former instance, therefore,
costs are clearly higher.
[0009] Moreover, the aforesaid volumetric bulk does not facilitate the placing of the pre-formed
frame into the form.
[0010] The object of the present invention is to provide a metal frame for reinforced concrete
such as obviates the difficulties existing in the known art, as mentioned above.
[0011] Such purpose is fulfilled by embodying'a metal frame characterized by the fact that
it comprises longitudinal rods and transversal rods reciprocally joined by articulated
joints.
[0012] The reciprocal mobility of the longitudinal rods and the transversal rods obtained
as a result of the articulated joints, makes it possible to reduce the volume of the
metal frame, thus overcoming the difficulties noted in the prefabricated frames at
present used.
[0013] The characteristics and advantages of the present invention will be more clearly
seen from the following description of a non-limiting exemplifying embodiment thereof,
illustrated in the attached drawings, in which:
FIGURE 1 is a perspective view of a metal frame according to the invention in operative
configuration;
FIGURE 2 illustrates the frame of FIGURE 1 in a reduced-volume configuration;
FIGURE 3 is a detailed illustration of a variant of the frame of FIGURE 1.
[0014] The frame according to the invention as illustrated, indicated generically by 10,
comprises four parallel, rectilinear, rough-surfaced steel rods, indicated by 11,
which will hereinafter be called length-members, articulated to a series of transversal
steel rods (only three of which are illustrated) bent in the form of a closed ring,
indicated by 12, which will hereinafter be called cross-members.
[0015] The connection between length-members 11 and cross-members 12 is effected by means
of rings 13 consisting of arched or hooped sections of steel bars which are welded
along each length-member 11 and through which pass the cross-members 12 as can be
clearly seen in FIGURE 1.
[0016] The length-members 11 are rigidly restrained in pairs by a series of transversal
bars 14 welded at their ends to two length-members 11 and another series of transversal
bars 14 welded at their ends to the other two length-members 11. The transversal bars
14 thus all have equal length, so as to keep the paired length-members parallel at
the same distance for both the pairs.
[0017] The cross-members 12 are quadrangular in shape and the length of the transversal
bars 14 is such that the pivoting between cross-members 12 and length-members 11 by
means of the rings 13 is at the corners of the cross-members 12.
[0018] The frame 10 which has been described and illustrated can have its volumetric extension
varied. In effect, the pivoting provided enables the cross-members 12 to describe
a rotation of 180° about their pivot- points, with a related oscillation of the two
pairs of length-members 11, parallel-wise one to the other, between a distanced position
and a juxtaposed position.
[0019] It is thus possible to open the frame 10 in a position of maximum volumetric extension
as shown in FIGURE 1, or to fold it back into a position of minimum volumetric extension
as shown in FIGURE 2.
[0020] This characteristic of the frame 10 according to the invention leads to a streamlining
and simplification of all the operations indirectly or directly required for reinforcing
concrete structures.
[0021] In the first place, the frame 10 can be volume- manufactured outside the building
yard by an industrial process.
[0022] During the transportation stage, the fact that the frame can be reduced in volume
makes it possible to optimize the ratio between quantity of material transported and
volume occupied.
[0023] The same consideration naturally also applies to the storage of the frames in question.
[0024] In the building yard, in the folded-back configuration of FIGURE 2, it is very manageable
and easy to place into the form. Once it has been so placed, it opens out into the
operative configuration shown in FIGURE 1.
[0025] If required, it can be locked in this configuration by means of iron wire or by hooks
suitably latched onto the cross-members, or by other means, to prevent reciprocal
movements of the component members, which could alter the operative configuration,
during the casting of the concrete.
[0026] The frame 10 as illustrated is particularly indicated for the reinforcement of girders
or beams or, in vertical configuration, of pillars.
[0027] The proposed arrangement of longitudinal and transversal rods, as also their shape
and number, can in any case vary depending on the building structure to be reinforced,
provided that the longitudinal rods and the transversal rods are reciprocally joined
by means of articulated joints such as allow an articulation between them of a kind
that will vary the volume of the frame.
[0028] In particular, FIGURE 3 shows a variant of the articulated joint. This variant consists
in the fact that, around each length-member 11, correspondingly to each cross-member
12, there is wound an iron wire 15 with a broader central turn which forms a ring
16 into which the cross-member 12 enters. The surface roughness of the length-members
11 which is provided for in order to ensure that they have perfect adherence in the
concrete, prevents any longitudinal slipping of the iron wires 15.
[0029] Both this and the previous solution featuring welded metal rings 13 show themselves
to be considerably economical for volume-production, and are at the same time functionally
effective.
1. A metal frame for building structures made of reinforced concrete characterized
by the fact that it comprises longitudinal rods (11) and transversal rods (12) reciprocally
joined by articulated joints (13,16).
2. A frame according to Claim 1, characterized by the fact that said articulated joints
are realized by means of rings (13, 16) which are secured to said longitudinal rods
(11) and into which the said transversal rods (12) fit.
3. A frame according to Claim 2, characterized by the fact that each of said rings
consists of an arched or hooped section (13) of rod welded to the longitudinal rod
(11).
4. A frame according to Claim 2, characterized by the fact that each of said rings
consists of a turn (16) of an iron wire (15) wound around the longitudinal rod (11).
5. A frame according to Claim 4, characterized by the fact that the surface of said
longitudinal rods (11) is rough, to prevent the longitudinal slipping of the wound
iron wires (15).
6. A frame according to Claim 1, characterized by the fact that said longitudinal
rods (11) are joined in pairs disposed on parallel planes and that said transversal
rods (12) are bent in the form of a closed ring, each restraining two contiguous pairs
of said longitudinal rods (11).
7. A frame according to Claim 6, characterized by the fact that each of said pairs
of longitudinal rods (11) consists of two parallel rectilinear rods rigidly connected
by transversal bars (14).