Note: Descriptions are shown in the official language in which they were submitted.
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SYSTEM FOR CONSTRUCTING A SEMI-PREFABRICATED BUILDING
Field and Obiect of the Invention
The invention is comprised within the field of building construction and more
specifically to building construction based on semi-prefabricated concrete
slabs, the
type of buildings which could be constructed with this process would be
buildings with
small dimensions as single-family dwellings, small warehouses or industrial
premises
and workshops.
State of the Art
Different systems for constructing buildings with reduced dimensions from mass
concrete are currently known, which concrete is poured in formwork plates or
molds for
its subsequent setting, mainly forming the structure of the dwelling such as
footings,
pillars, floorings, etc.
Different systems for constructing buildings from prefabricated concrete slabs
are also known which are arranged on the sole or floor of the building to
directly form
the walls, floor and roof thereof. Said slabs are normally brought already
shaped to the
building site but in some cases they are molded "in situ", such slabs are
usually formed
leaving gaps therein for the windows and doors of the building.
The stowing operations of the mentioned slabs, which have large weights, are
normally carried out through expensive installations for lifting them such as
cranes with
a considerable size, which must have a large amount of space in the
construction site
for their stable locking to the ground, having to use auxiliary means such as
for
example hooks, straps or similar elements for securing and handling the
mentioned
slabs during the stowing and transport operations thereof. In addition to the
high costs
and the large amount of time consumed in the mentioned stowing operations,
accidents usually occur during such operations due to the breakage of the
auxiliary
securing elements which can trigger both personal and material losses if the
slab falls
from a great height, both the slab itself and the elements of the building
being able to
be completely or partially lost.
Due to the above, a need has been detected to provide a process for
constructing the mentioned type of buildings which, starting from simple
lifting means
for lifting the slabs, achieves that the stowing operations are highly simple
and with a
low cost, to that end the use of a plurality of lifting means fixed to the
base or sole of
the building has been considered, which means are located in the gaps that the
slabs
have for the arrangement of windows and doors, anchoring means for anchoring
the
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slab to the mentioned lifting means being arranged in said gaps, the slabs
being lifted
and placed in an erect position in a controlled and highly safe manner.
This objective is achieved by means of the invention as it is defined in claim
1,
the preferred embodiments of the invention are defined in the dependent
claims.
Description of the Invention
The present invention relates to a system for constructing a semi-
prefabricated
building which is formed by a plurality of slabs corresponding to the outer
walls, floor
and roof of the building, the outer wall slabs having a plurality of gaps
corresponding to
the windows and doors.
The system is characterized in that two of the outer wall slabs are located
parallel to one another in a horizontal position on the floor slab, one of the
sides of
each wall being aligned respectively with one of the parallel edges of the
floor slab,
lifting means being fixed on the floor slab, which means have a fixed part and
another
moving part with respect to said slab, being located in the gaps of the
windows of the
outer wall slabs and the moving part of said lifting means remaining joined to
anchoring
elements located in the mentioned gaps and fixed to the slabs, the outer wall
slabs
being lifted due to the lowering thereof with respect to their lower edge
until said slabs
are located in an erect position and a support structure subsequently being
placed on
the gaps of the windows opposing one another of each of the outer wall slabs,
which
support structure is in turn fixed to both slabs by means of fixing elements,
repeating
the described operations for the case of the other two outer walls and joining
the slabs
of the four outer walls to one another.
Furthermore, the roof slab is located in the gap delimited by the four outer
walls,
and supported on the floor slab, which roof slab has a plurality of openings
located in
coincidence with the position of the lifting means used in the previous steps,
the
moving part of said lifting means being joined to anchoring elements located
in the
mentioned openings, the roof slab being lifted to a height above the height of
the outer
wall slabs, the roof slab being joined to the upper edge of the slabs of the
four outer
walls.
In this way, due to simple lifting elements, the walls of the building are
placed in
a vertical position and the roof is lifted quite simply, not being necessary
to use
expensive lifting means such as cranes. Furthermore, with the described
configuration
of the system, the same lifting elements can be used to lift both the outer
wall slabs
and the roof slab.
The outer wall slabs can have at least one gap for the windows.
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The lifting means can in turn comprise a plurality of hydraulic jacks, at
least one
of said hydraulic jacks being locates in at least two of the gaps of the
windows of the
outer wall slabs.
The system can operate with a single lifting element per outer wall slab (a
single
gap of a window) provided that the weight of the slab is such that it is
supported by the
mentioned hydraulic jacks, in the event that said weight is exceeded, more
than one
lifting elements must be used for each slab, its number being determined based
on the
properties of each jack and the weight of the slab.
To join the outer wall slabs to one another, at least two metal reinforcing
bars in
the form of an angle bracket can be used, one of them being located on the
inner face
of the mentioned slabs and the other one on the outer face and being fixed to
one
another and to the corresponding slab, subsequently pouring mass concrete.
A stable and safe joining between the slabs of the four outer walls is thus
achieved.
The outer wall and roof slabs can have a plurality of pins perpendicular to
the
joining edges between said slabs, the ends of said pins being curved.
With the described shaped and placement of the pins it is achieved that the
joinings between slabs are more rigid and resistant to the different stress
which the
building is subject to.
The pins corresponding to the roof slab can initially be bent and when the
roof
slab is lifted above the upper edge of the outer wall slabs, said rods are
straightened.
It is thus possible for the roof slab to fit in the gap left by the slabs of
the four
outer walls when said roof slab is deposited on the floor slab, to later, once
said roof
slab has been lifted, straighten said pins which will be useful as resistant
elements in
the joining of the roof slab with the outer wall slabs.
The anchoring elements, located in the gaps of the windows of the outer wall
slabs and which are connected to the moving part of the lifting means,
comprise at
least one rod having a curved central portion for its seating on said moving
part and the
ends of which are joined to the slab in the stage of molding it.
Said rods are useful for hanging the slabs on the moving part of the lifting
means, which moving part will have a stem perpendicular to the direction of
movement
of said moving part with respect to the fixed part.
The support structure can further be formed by two parallel bars, on each of
which the fixing elements for fixing the support structure to the outer wall
slabs are
located, said joining means comprising two clamps, one of which is located on
the
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inner face of the wall slab and the other of which is located on the outer
face thereof,
respective threaded bushings being located after said clamps, which bushings
will have
the possibility of being threaded on threaded sections made in each of the
bars.
By means of the mentioned clamps, the support structure and the two slabs
connected by it are aligned and solidly joined to one another, forming in turn
a stable
structure preventing said slabs from falling to the ground due to their own
weight.
Finally, the reinforcing bars used for joining the roof slab with the outer
wall
slabs comprise an inner angle bracket and an outer mold provided on one of its
faces
with a wavy surface, defining a projection in the cornice of said roof slab
after it is
joined to the mentioned outer wall slabs by means of mass concrete.
The integral joining between the roof slab and the outer wall slabs is thus
achieved, there being a wavy ending in the cornices of the building which has
a great
aesthetic value.
Description of the Drawings
A series of drawings is very briefly described below which aid in better
understanding the invention and which are expressly related to several
embodiments of
said invention, which are set forth as illustrative and non-limiting examples
thereof.
Figure 1 shows a perspective view of an example of a building constructed by
means of the system object of the present invention.
Figure 2 shows a plan view of an example of a distribution in which the
different
rooms of a building constructed by means of the system object of the present
invention
can be seen.
Figure 3 shows an upper plan view of the floor slab and of the two slabs
corresponding to two of the parallel outer walls in a first step of
constructing the
building according to a system object of the present invention.
Figure 4 shows a plan view similar to that shown in Figure 3 for a second
variant of the system object of the present invention in which the outer wall
slabs and
the floor slab will be joined.
Figures 5A to 5C show respective sectional views according to section plane I-
I
of Figure 3 in which the different stages of assembling two of the outer walls
of the
system object of the present invention can be seen.
Figure 6 shows a sectional view according to section plane I-I of Figure 3,
showing a last step of assembling two of the outer walls when they are erect,
as well as
a detail of the joining of the auxiliary structure to the outer walls.
Figure 7 shows a plan view of the floor slab and the four slabs corresponding
to
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the outer walls before they are joined.
Figure 8 shows an upper plan view of the floor slab on which the roof slab is
located before being lifted on it.
Figures 9A and 9B show a sectional view according to section plane II-II of
5 Figure 8, showing the respective steps of the process for lifting the roof
slab with
respect to the floor slab and the outer wall slabs.
Description of an Embodiment of the Invention
Figure 3 shows a plan view of a first step of the building process using the
system object of the present invention. Specifically a baseplate (1) is
observed which
forms the floor of the dwelling and is formed by a prefabricated concrete
slab, on which
two of the outer walls (2-2') are arranged, said outer walls (2-2') are also
prefabricated
concrete slabs and each of them has two gaps (3-4) and (3'-4') respectively
for the
windows, although it could have any number of windows such as a single window
for
example.
The mentioned gaps (3-4) and (3'-4') have been shaped at the same time as
the slab itself is shaped by molding by means of mass concrete.
Inside the gaps left by the windows and anchored to the baseplate (1), there
are
arranged respective lifting means (5-6) and (5'-6') consisting particularly of
hydraulic
jacks, also being able to be pneumatic jacks or any other similar lifting
means.
The windows in turn have anchoring elements, said elements, in this
embodiment of the invention, are corrugated steel rods (7-7') having a
curvature in their
central area and which are introduced (inserted) in the concrete in the stage
of shaping
the outer wall slabs (2-2'). The curved area of said rods (7-7') defines an
anchoring
point with the lifting means (5-6) and (5'-6') and more specifically with the
moving part
(8) thereof through a stem (9) perpendicular to said moving part.
The lifting means (5-5') and (6-6') will be joined to one another by means of
respective bars 31, for the purpose of maintaining the relative position
between them
and will in turn be fixed to the floor slab (1), using to that end known means
such as
screws and rivets. The lifting means (5-6) and (5-6') have the possibility of
rotation with
respect to the floor plate (1) thanks to a ball joint (10), said rotation
occurring in a plane
perpendicular to the floor slab (1) and to the outer wall slabs (2-2')
themselves. Given
that the outer wall slab (2) is linked the rod (7) which is in turn connected
to the moving
part (8) of the lifting means and that the lifting means (5-6) remain fixed
with respect to
the floor slab (1), when said lifting means (5-6) are actuated, the moving
elements (8)
move with respect to the fixed elements and therefore the floor slab (1) and
the outer
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wall slab (2) rotate or better said, it is lowered with respect to an axis
coinciding with
one of the lower edges for the support on the floor slab (1).
This lowering movement can be seen clearly in Figures 5A-5C. The rod (7) will
logically be able to rotate with respect to the stem (9) to thus be able to
convert the
linear movement of the lifting element (5-6) into a lowering movement of the
outer wall
slab (2).
The process for lifting is prolonged until it is achieved that the outer wall
slab (2)
is completely erect and therefore perpendicular to the floor slab (1).
Both outer wall slabs (2-2') are lifted in one and the same operation, the two
standing walls being located in a parallel manner. An auxiliary support
structure (11)
which is introduced through the gaps (3-3') or (4-4') corresponding to
opposing
windows corresponding to each of the outer wall slabs (2-2') is used to
prevent said
outer wall slabs (2-2') from falling due to their own weight.
Said support structure (11) is formed by at least two parallel bars (30)
joined to
one another by a plurality of bars which are inclined with respect to them,
determining a
spatial structure. Joining means for the joining to the windows are arranged
on the free
ends of each of said bars (30), specifically each of the bars will be joined
to one of the
lateral sides of the gaps of the windows. The mentioned joining means comprise
two
clamps (13-14), one of which (14) is located on the inner face of the wall
slab and the
other of which (13) is located on the outer face thereof, as can be seen in
the detail of
Figure 6, respective threaded bushings (15) being located after said clamps,
which
bushings will have the possibility of being threaded on threaded sections made
in each
of the bars (30). In a preferred embodiment of the invention, the mechanisms
that are
currently used to place and lift scaffolds, which will be welded to the ends
of the bars
(30), leaving enough space between them greater than the thickness of the
slabs
forming the outer walls (2-2"), will be used.
As a result of the structure (11) and its due fixing to the outer wall slabs
(2-2'), it
is achieved that the stability of the assembly is greater and that said slabs
do not fall to
the ground due to their own weight.
The same process is carried out with the slabs corresponding to the other two
outer walls (16-16') of the building which are perpendicular to the slabs (2-
2'), i.e. they
are located horizontally on the floor slab (1), lifting means (5-6) and (5'-
6') being used,
being able to use the same elements for the outer wall slabs (2-2') or other
independent elements and a similar support structure (11), thus stowing the
four outer
wall slabs (2-2') and (16-16') of the building to subsequently join them to
one another,
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as can be seen in Figure 6.
The slabs of the four outer walls (2-2') and (16-16') are joined perpendicular
to
one another by means of corrugated rod pins (17) with bent ends integrated in
the
slabs themselves during the process of prefabricating such slabs, such pins
(17)
correspond to the ends of the mat reinforcement which are included inside the
slabs
during the "in situ" molding thereof.
The slabs of the four outer walls (2-2') and (16-16') are joined using
respective
metal reinforcing bars (18-19) for each of the edges of the building.
Specifically, two
metal reinforcing bars in the form of an angle bracket will be used, one of
them (18)
being located on the inner face of the mentioned slabs and the other one (19)
being
located on the outer face and being fixed to one another and to the
corresponding slab
to subsequently pour the mass concrete in the gap existing between contiguous
slabs
and thus join slabs of the four outer walls (2-2') and (16-16') in a safe and
long-lasting
manner.
The walls of the house are thus lifted, only the roof remains to be lifted,
which is
lifted as follows.
Figure 8 shows how the roof slab (20) is located on the floor slab (1) in the
gap
left by the four outer wall slabs (2-2') and (16-16') once they have been
joined. The roof
slab (20) has at least four openings (21), circular in this case, to allow the
passage of
respective lifting means (5-6) and (5'-6'). Each of the openings (21) has
engaging
means similar to those used in the case of the outer wall slabs, which means
consist of
bent rods (22) introduced in the roof slab (20) itself during the process for
molding such
slabs, which rods define a connection point with the lifting means (5-6) and
(5'-6') such
that when the moving part of the four lifting means is lifted at the same
time, the roof
slab (20) is in turn lifted parallel to the floor slab (1) until reaching a
height
approximately equal to the height of the outer walls. On this occasion, the
lifting means
(5-6) and (5'-6') will be fixed to the floor slab (1) such that its rotation
with respect to
said slab is not possible, using a bushing fixed the floor slab (1) or a
similar element
which can retain the fixed part of the lifting means (5-6) and (5'-6') without
it rotating.
The roof slab (20) in turn has a plurality of pins (23) by way of a hook made
of
corrugated steel, integrated in the slab in the molding process using a mat
reinforcement, with the particularity that said pins (23) are bent at the time
of placing
the roof slab (20) on the floor slab (1) so that said roof slab (20) and its
corresponding
pins (23) fit in the gap between the outer wall slabs. Once the roof slab (20)
has been
lifted, the mentioned pins (23) are straightened, extending beyond the upper
edge of
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the outer wall slabs (2-2') and (16-16').
As can be seen in Figure 9A, the upper edge of the outer wall slabs (2-2') and
(16-16') and the roof slab (20) are joined due to the mentioned pins (23) and
the pins
(24) of the slabs forming said outer walls, with the aid of respective metal
reinforcing
bars that are normally formed as a sheet, one of which (25) is angular and
located on
the inner face of both the roof slab (20) and of the corresponding outer wall
slabs and a
caisson (26) or outer mold which is fixed to the outer face of the outer wall
slabs, there
being defined a space on which the mass concrete will be poured to join the
mentioned
slabs.
Figure 4 shows a variant of that shown in Figure 3, in which the floor slab
(1)
has mortises (27) for introducing the lower pins of the outer wall slabs (2-
2') once they
have been lowered and completely erected.
The windows at their upper part can have moldings coupled thereto (Figure 1)
with a staggered configuration to make the architectural assembly of the
dwelling more
aesthetic, such moldings can be independent for each side of the frame of the
window
or can be one-piece, being coupled directly to the frame of the mentioned
window.
The mentioned caisson (26) used to join the roof slab (20) with the outer wall
slabs (2-2') and (16-16') can have a wavy configuration, being able to define
a
staggering with a wavy profile, as can be seen in Figure 1, to imitate the
appearance
that a conventional roof formed from tiles would have and thus make the
building more
aesthetic.
Figure 2 in turn schematically shows an example of the inner distribution of a
building constructed by means of the method object of the present invention,
said
building having a rectangular prismatic base and in which a series of rooms
(40-46)
can be seen and in which a plurality of support columns (35) arranged at
specific points
of the building such that they can support the weight of the roof slab (20) is
especially
shown. Such columns will be placed immediately before removing the lifting
means (5-
6) and (5'-6') when the roof slab (20) has been completely lifted and it has
been joined
with the outer wall slabs (2-2') and (16-16'). The mentioned columns will be
securely
joined to both the floor slab (1) and the roof slab (20) using known joining
means.
