[0001] The present disclosure refers to a stairway and to a method for making it.
[0002] In the building field, the need to provide a connection between different floors
or levels of a same building arises very frequently; such a need is usually met by
making one or more flights of stairs.
[0003] Sometimes the space available for making a stairway is reduced and therefore it is
necessary for different sections of a same stairway to have orientations different
from each other, in order to contain the dimensions in plan view of the stairway within
a stairwell of limited size.
[0004] The recognized need to take up less room than the conventional stairways has led,
e.g., to the introduction of the so-called spiral stairways. Historically, the first
uses of spiral stairways were recorded for access to the top of towers, minarets,
monumental columns or pillars.
[0005] Over the centuries, stairway construction techniques have evolved in the direction
of rapidity and inexpensiveness of design, making and installation.
[0006] In the known art, the making of a concrete stairway requires on-site making of one
or more formworks for the entire stairway. Formworks are hand-made with wooden boards
or sheet metal and must be suitably supported to extend between the floors to be connected.
Subsequently, concrete casting into the formworks occurs and, once concrete has set,
formwork removal and stairway finishing are carried out. Therefore, the formworks
compose a casing into which fluid-state concrete is cast. After setting, the casting
has achieved a mechanical strength such as to ensure absorption of stresses to which
the structure is subjected, and formwork dismantling ensues.
[0007] Such a making mode is very toilsome, complex and expensive, requiring skilled labour
and long times for the making. Even the subsequent disposal of the formworks represents
a problem, due to the fact that, usually, wood mixed up with plastics sheets is present
in the formworks.
[0008] Moreover, there is the need to make a stairway having an intrados with a curved and
well-jointed surface, because this is an aesthetical requirement much sought-after
by customers.
[0009] The above-described making mode entails very large dimensional tolerances, which
prove to be substantially incompatible with said need. To solve this drawback, a phase
of finishing the stairway is resorted to in order to make the intrados surface free
from asperities, steps and anomalous curvatures; this phase is very difficult and
toilsome, as well as not always satisfactory from the standpoint of the final result.
[0010] Modular stairways of concrete, wood or other materials are also found in the known
art. Such stairways consist of sectional prefabricated modules, each corresponding
to a step, which are assembled together usually by screws and bolts or with other
assembling modes. The modules are all identical to each other and are mass-produced.
Examples of such modular stairways are disclosed by Austrian patent No.
AT 385 074, German patent No.
DE 336 074, German patent No.
DE 809 483, U.S. patent No.
US 6,112,480, international patent application
WO 02/100149.
[0011] The making of a modular stairway is faster and simpler than a making entirely on-site
as described above.
[0012] However, the inventor of the subject of the present disclosure has noticed that the
fact of having to use modules identical to each other and of predetermined shape seriously
limits the possibility of making a custom stairway for a stairwell of specific size,
all the more so when space is limited and it is necessary to make a curved or spiral
stairway. In fact, the designer's freedom is strongly limited, or even cancelled,
by having to use modules that are identical and of standard shape and dimensions already
preset by others, i.e. by the makers of the modules themselves.
[0013] Moreover, due also to the large dimensional tolerances linked to module making, jointing
between modules proves to be rough, therefore it is very difficult to make a stairway
having an intrados with a curved and well-jointed surface without resorting to subsequent
toilsome finishing phases.
[0014] Therefore, in order to obviate at least one of the drawbacks mentioned above with
reference to the known art and/or achieve further advantages, the inventor has provided
a method for making a stairway according to claim 1, a stairway according to claim
14, and an apparatus according to claim 17.
[0015] Secondary features of the subject of the present disclosure are set forth in the
corresponding dependent claims.
[0016] The subject of the present disclosure provides some relevant advantages.
[0017] The method which is the subject of the present disclosure is useful to render the
making of a stairway more effective and cheaper.
[0018] In fact, the method envisages the making of a substantially modular stairway, wherein
the modules, each corresponding to a step, are formworks which are shaped each depending
on the end stairway to be obtained, and moreover they are "disposable" formworks,
i.e. they are intended to remain included in the stairway following the casting of
a filler material (which is, e.g., concrete). This allows a greater quickness in making
the stairway, as the assembling of a plurality of individual prefabricated formworks
is much easier than the on-site construction of a formwork for the entire stairway.
Moreover, the method is useful to reach a higher precision of making, because the
formworks can be suitably shaped so that the respective external surfaces basically
correspond to the faces of the respective steps. Thus, the formworks may be accurately
custom-made to obtain precise jointings between different steps.
[0019] Basically, with respect to the conventional methods based on concrete casting, the
jointing between adjacent steps is remarkably improved and, for instance, in some
embodiments, it is easier to obtain an intrados with a curved and well-jointed surface.
[0020] In particular, a design phase which includes a phase of custom computing the dimensions
and shape of each of said formworks, on the basis of the dimensions of a stairway
installation site, is provided. The shaping of the individual formworks is based on
such a design phase.
[0021] Basically, it is possible to make a custom stairway, comprising a plurality of steps
all different from each other and made in a precise way thanks to the exact dimensioning
of the required individual formworks and to their subsequent production on the base
of the exact dimensioning; in an embodiment, the production is carried out, e.g.,
by milling with a numerical-control milling machine.
[0022] Moreover, according to some embodiments of the present disclosure, the modular stairway
is made with light-weight hollow formworks; accordingly, the transporting and assembling
phases are less burdensome than other known methods.
[0023] A major contribution to the formwork lightness feature is attained, as in some embodiments
the formwork is obtained from a block of wood-concrete. In fact, wood-concrete comprises
wood chips mixed with a concrete matrix; as a result it is lighter in weight than
solid blocks of concrete. By using this material, it is possible to reach a weight
of the finished stairway that is about one-half the weight of a stairway made with
conventional methods.
[0024] In other embodiments the formworks are obtained from polystyrene blocks, thereby
attaining an even more marked reduction of the weight of the finished stairway. In
addition, polystyrene is particularly easy to work.
[0025] Therefore, the method is particularly suitable for all those applications for which
it is advisable to minimize constraint reactions from the supporting walls (e.g. in
the refurbishing of old buildings) by lightening the load on the floor slabs.
[0026] In some embodiments, formwork shaping is carried out by material-removal manufacturing.
[0027] To be more specific, in some embodiments the manufacturing is carried out by milling
from blocks of material; milling allows to reach high accuracy, which would not be
achievable by using the usual moulding/casting methods. Milling further allows a rather
rapid making of the formworks.
[0028] This mode is particularly indicated for shaping wood-concrete blocks, which can be
milled without particular difficulty, and also for blocks of polystyrene or of other
workable material.
[0029] In other embodiments, formwork shaping is carried out by laser cutting or by hydrojet
cutting.
[0030] These modes, that allow to obtain high manufacturing accuracy too, are particularly
suitable for shaping polystyrene blocks, but can anyhow be applied also to blocks
of wood-concrete or of other workable material.
[0031] The polystyrene blocks might also be shaped otherwise, e.g. by hot-wire cutting.
[0032] In case polystyrene blocks are used, the strenght of the obtained formwork may be
enhanced, after the shaping phase, by coating the surface of the formwork with a hardening
resin, e.g. a polyurethane resin, or with fiberglass.
[0033] Basically, in such embodiments, the phase of manufacturing each formwork is carried
out by selective removal of material from an initial solid block, in order to obtain
a formwork having the desired dimensions and shapes, inclusive of recesses in the
formwork body and recess openings to the outside; it is therefore a three-dimensional
shaping.
[0034] Such shaping is carried out by using, e.g., a numerical-control machine tool, which
is managed by a computer. To obtain maximum versatility of use, the machine tool is
of the type having five or more axes.
[0035] In principle, it is possible to use blocks of other materials and/or other machine
tools, which allow to machine the block by selectively removing material therefrom
to obtain a formwork in the desired shape. The material will be selected among those
allowing to obtain a formwork having a mechanical strenght adequate to the stairway
to be made. Moreover, it will be appreciated that, since the formworks are "disposable",
the method that is the subject of the present invention allows to get rid of the formwork
disassembling phase, which instead is necessary with other stairway making methods.
In some embodiments, the method provides a phase of assembling in which the joining
between adjacent formworks is obtained by connecting means making a tongue-and-groove
coupling between two adjacent formworks. This allows a very rapid and simple assembling,
providing no screwing steps or more complex connecting methods.
[0036] In some embodiments, a phase of arranging reinforcements in the formworks before
proceeding with casting the filler material is provided, so that the structural strength
of the stairway be enhanced by the reinforcements themselves, which e.g. are metal
bars. In some embodiments, the stairway is produced using fire-resistant, sound-absorbing
and ecological materials.
[0037] Therefore, it will be better appreciated how the method of the present disclosure
also allows to reduce noise due to treading on the steps.
[0038] Moreover, the method enables the use of a renewable material such as wood in the
wood-concrete blocks.
[0039] The design phase provides, e.g., the adoption of antiseismic criteria in computing
the dimensions and shape of the entire stairway and the individual steps.
[0040] Other advantages, features and operation steps of the subject of the present disclosure
will be made evident in the following detailed description of preferred embodiments
thereof, given by way of example and not for limitative purposes. Reference will be
made to the figures of the annexed drawings, wherein:
■ Figure 1 shows a top perspective view of a formwork according to the present disclosure;
■ Figure 2 shows a front perspective view of the formwork according to Figure 1;
■ Figure 3 shows a perspective view of a phase of manufacturing the formwork according
to Figure 1;
■ Figure 4 shows a top and side perspective view of a plurality of formworks according
to the present disclosure, in a phase of assembling a stairway;
■ Figure 5 shows a top and side perspective view of the formworks according to Figure
4, in an assembled configuration;
■ Figure 6 shows a bottom perspective view of the formworks according to Figure 5,
wherein a stairway intrados is visible;
■ Figure 7 shows a top and side perspective view of a stairway in a making phase according
to the present disclosure;
■ Figure 8 shows a top perspective view of the stairway according to Figure 7, in
another making phase;
■ Figure 9 shows a perspective view of a detail of the stairway according to Figure
8; and
■ Figure 10 shows a top and side perspective view of part of the stairway according
to Figure 7 in still another making phase.
[0041] Referring initially to Figure 1 and Figure 2, a formwork according to the present
disclosure is shown in two different views and is generally denoted by reference number
1.
[0042] As will be made apparent hereinafter, the formwork 1 is of the so-called "disposable"
type, i.e. it remains permanently included in the end structure of a stairway 100.
In other words, the formwork 1 is not removed subsequently to the making of the stairway,
as it happens with formworks commonly used in the building field, but on the contrary
the formwork 1 is an integral part of the stairway 100 and therefore carries out a
structural function in the stairway 100 when the latter is completed.
[0043] In particular, each formwork 1 goes to form a respective step 110 of the stairway
100, therefore the formwork 1 has a shape that corresponds to the shape of the respective
step 110.
[0044] The formwork 1 has a substantially prismatic shape. In the example shown, it has;
- a first face 1 a, or top face, corresponding to a treadable region 12 of the respective
step 110,
- a second face 1b, or bottom face, opposite to the first face 1a and corresponding
to an intrados portion 6 of the stairway 100,
- a third face 1c and a fourth face 1d, which are intended to face on respective adjacent
formworks,
- a fifth face 1 e, corresponding to a riser face of the respective step 110,
- a sixth face 1f and a seventh face 1g, which are side faces corresponding to the bases
of said prismatic shape.
[0045] In particular, the third face 1c is interposed between the first treadable face 1a
and the second intrados face 1b, and is intended to face an adjacent formwork 1 placed
at a higher height; the fourth face 1d is interposed between the second intrados face
1b and the fifth riser face 1e, and is intended to face an adjacent formwork 1 placed
at a lower height.
[0046] Moreover, the first treadable face 1 a and the fifth riser face 1e are orthogonal
to each other. In some embodiments of the present disclosure, the second intrados
face 1b has a curved surface.
[0047] It has to be noted that by "substantially prismatic" shape it is meant that the formwork
1 has a shape resembling that of a prism, though it is not required that it be a geometric
prism. E.g., the sixth face 1f and the seventh face 1g may be not parallel to each
other and be of dimensions different from each other; the faces 1a, 1b, 1c, 1 d, 1
e, 1 f, 1g may have curved surfaces.
[0048] The formwork 1 is a hollow body, substantially it is a casing of suitable thickness
(in the shown example the thickness is comprised between 2 and 8 cm), having an internal
recess 2 which is open on one or more faces of the external surface of the formwork
1. In particular, the third face 1c and the fourth face 1d have respective access
openings 23, 24 for accessing the internal recess 2; also the first treadable face
1 a has openings 21 for accessing to the internal recess 2. The fifth riser face 1e
and the side faces 1f, 1g have continuous surfaces, in other words are devoid of access
openings for accessing the internal recess 2.
[0049] In a variant embodiment (visible e.g. in the first base formworks 1 in Figures 4
and 5), the openings 21 of the first treadable face 1a and the openings 23 of the
third face 1c are contiguous to each other; in other words, such openings 21, 23 extend
to the edge 1 q between the first face 1 a and the third face 1 c, which edge 1 q
is therefore interrupted at said openings 21, 23.
[0050] In the example, the formwork 1 comprises a partition 25, substantially parallel to
the side faces 1f, 1g and arranged in an approximately intermediate position between
said side faces 1f, 1g, partitioning the internal chamber 2 into two compartments;
each compartment has access openings 21, 23, 24 on the corresponding faces 1a, 1c,
1d. Moreover, the partition 25 has a function of reinforcing the formwork 1.
[0051] Furthermore, the formwork 1 is provided with connecting means for allowing an assembling
thereof with the adjacent formworks. In the example, the connecting means achieves
a tongue-and-groove coupling, comprising male members 3 (e.g. pegs or tenons) and
female members 4 (e.g., holes or mortises).
[0052] Such connecting means 3, 4 is arranged on the third faces 1c and on the fourth faces
1 d, e.g. at opposite parts of the faces themselves; for instance, it may be provided
that each third face 1c and each fourth face 1d be provided with a male member 3 and
a female member 4, or it may be envisaged that each third face 1c be provided with
at least two male members 3 and each fourth face 1 d be provided with at least two
corresponding female members 4, or vice versa.
[0053] Basically, the joining between two adjacent formworks 1 is achieved by a tongue-and-groove
joint coupling.
[0054] Each formwork 1 is obtained in the desired shapes and dimensions by three-dimensional
shaping of a respective block 16 of material; in Figure 3 a shaping by milling is
exemplarily shown.
[0055] In an embodiment, the blocks 16 are made of wood-concrete; in particular, they are
made of a material comprising wood chips homogeneously distributed in a cement matrix,
e.g. Portland cement, acting as a binder between the wood chips.
[0056] In the example, said wood-concrete comprises wood chips in an amount of 80% by weight
and concrete in an amount of 20% by weight. In the example, the wood chips are pinewood
chips and have dimensions in the order of 3-6 cm in length and a thickness of some
millimetres.
[0057] Therefore, wood-concrete blocks 16 are provided, e.g. initially parallelepiped-shaped,
that are machined by a milling machine 17 to obtain the formworks 1, which thereby
are custom-made.
[0058] Starting from a wood-concrete block 16, the milling machine 17 machines and shapes
such a block 16 to give it the shape and dimensions desired for the relevant formwork
1 and makes therein the internal recess 2 and the openings 21, 23, 24, leaving the
partition 25.
[0059] By repeating the process for the other blocks 16, a plurality of wood-concrete formworks
1 is thus provided.
[0060] In the example, the phase of producing the formworks 1 by milling is carried out
by using a milling machine 17 having five or more axes.
[0061] In particular, the milling machine 17 is of numerical-control type, it being controlled
by a computer 18. Therefore, the milling machine 17, by being a numerical-control
one, allows to make the formworks 1 in a very accurate way, and with a working contribution
from a single unskilled operator.
[0062] In another embodiment the blocks 16 are made of polystyrene, e.g. EPS with a density
of 35 kg/m
3.
[0063] The polystyrene blocks 16 are shaped by the milling machine 17 to obtain the formworks
1.
[0064] Alternatively, the shaping of the blocks 16 may be carried out by using a laser cutting
machine, or a hydrojet cutting machine, also these being numerical control ones and
operating on five or more axes. In case of polystyrene blocks 16, also a hot-wire
cutting machine might be used.
[0065] In case polystyrene blocks 16 are used, the formwork 1 obtained following the shaping
operation is subjected to a phase of coating with resin: the surface of the formwork
1 (both on the external faces 1 a, 1b, 1 c, 1 d, 1 e, 1 f, 1g, and in the internal
recess 2) is coated with a hardening resin, which e.g. is distributed by spraying
or brushing. This hardening resin is, e.g., a polyurethane resin and/or a fiberglass-containing
resin. Thus, a formwork 1 of resin-coated polystyrene is obtained, i.e. a formwork
having a polystyrene core coated by a layer of hardened resin which sensibly improves
its mechanical resistance properties. The thickness of the resin layer is, e.g., of
1-2 mm; such thickness may be higher for bigger formworks 1, i.e. for those that are
subjected to greater mechanical stresses. The thickness of the walls or faces of the
polystyrene formwork is, e.g., of between 2 and 8 cm.
[0066] The phase of making the formworks 1 occurs in a workshop and the formworks 1 thus
obtained are subsequently transported on the site where the stairway 100 is to be
installed. Basically, the formworks 1 are prefabricated in the workshop and ready
for use.
[0067] Prefabrication of the formworks 1 occurs on the basis of a design of the stairway
100.
[0068] The designing of the stairway 100 includes a phase of custom computing the dimensions
and features of the stairway 100 itself, given the dimensions (encumbrance in plan
view, difference in level between floors to be connected,...) of a stairwell or other
installation site and the specifications required, e.g., by technical rules for building.
In particular, the computing phase determines in a custom-made manner the dimensions
and the shape of each step 110 and therefore of each formwork 1.
[0069] The shaping of each block 16 to obtain the respective formwork 1 is based on the
dimensions and shape of the step 110 which have been determined in the design phase.
[0070] The design phase may also be made through known algorithms, typically via a software.
E.g., CAD/CAM systems are used, which, in an embodiment, are directly integrated with
the computer 18 controlling the milling machine 17 (or other machine tool for the
three-dimensional shaping of the blocks 16), making the designing of the stairway
100 even more rapid.
[0071] Basically, an apparatus for making the formworks 1 is provided, comprising a computer
18 and a shaping machine tool 17. The computer 18 is configured for inputting data
related to the dimensions of the installation site for the stairway 100 and is further
configured for executing a custom computing software for each formwork 1 on the basis
of the dimensions of the installation site. The shaping machine tool 17 is configured
for shaping a plurality of blocks 16 on the basis of the results of the custom computing,
to the obtainment of the plurality of formworks 1.
[0072] In particular, the apparatus includes storage means for storing the dimensions of
the installation site and/or the results of the custom computing.
[0073] The stairway 100 may be designed with steps 110 all different from each other, therefore
also the formworks 1 are made as unique pieces, different from each other. In other
words, the method allows a custom and individual making of a stairway 100, which therefore
can be designed in the best way, to best be fitted in a stairwell of preset dimensions.
[0074] Figures 4 to 10 show subsequent phases of making the stairway 100.
Figure 4 shows a plurality of formworks 1 that are joined to each other in sequence,
by a phase of on-site assembling in which the formworks 1 are arranged adjacent and
aligned in a preset sequence along a direction 150 of ascent-descent of the stairway
100.
[0075] As mentioned, the formworks 1 may be, e.g., all different from each other; such a
preset sequence of the formworks 1 is therefore that univocally determined in the
design phase and allowing to obtain the stairway 100 in the design dimensions and
features.
[0076] In particular, Figure 4 shows the assembling of a formwork 1 with another adjacent
formwork, denoted by reference number 5, which has already been laid; thus, a stairway
section 100 shown in Figure 5 is obtained.
[0077] In the assembling phase, a tongue-and-groove joint coupling is achieved between the
male 3 and female 4 members on the fourth face 1d of the formwork 1 and the corresponding
female 4 and male 3 members on the third face 1c of the adjacent formwork 5.
[0078] Thanks to the custom design phase, the dimensions of the fourth face 1d of the formwork
1 correspond to, and even match, the dimensions of the third face 1c of the adjacent
formwork 5, as well as there is a correspondence between the connecting means 3, 4
of the formwork 1 and the connecting means 4, 3 of the adjacent formwork 5.
[0079] Moreover, the formworks 1, 5 are arranged so that the access openings 24 of the fourth
face 1d of the formwork 1 be aligned with respective access openings 23 of the third
face 1 c of the formwork 5; therefore, it is obtained a channel 29 (or, in the present
case, two channels 29) extending through the recesses 2 of the formworks 1, 5 along
the direction 150 of ascent-descent.
[0080] The assembling phase can also be carried out by hand, as it merely comprises a tongue-and-groove
joint coupling and the formworks 1, 5 are rather light-weight. As the case may be,
it may be necessary to assemble a simple scaffolding or other similar structure (not
shown) to support the whole of the formworks 1, 5 during the assembling. The assembling
phase proceeds by joining in sequence one formwork 1 after the other, until completing
the skeleton 7 of the stairway 100, shown in Figure 7.
[0081] Basically, the stairway 100 is a modular stairway, whose modules are represented
by the formworks 1; it has to be noted, however, that such modules in the example
are all different from each other.
[0082] Therefore, a sequence of formworks 1, 5, adjacent to each other and connected via
the connecting means 3, 4, is obtained, which are arranged to take up a stairwell
(not shown in the figures as not strictly necessary to the present description) to
act as vertical connection between an upper floor 13 and a lower floor 14.
[0083] The skeleton 7 of the stairway 100 has a step-shaped first treadable side 12, and
a second intrados side 6 opposite to the first treadable side 12.
[0084] The second intrados side 6 is designed so as to have a continuous even surface; in
other words, the second intrados side 6 is a curved surface that (within the limits
of the tolerances for the making and joints) has no gaps, steps, and/or sudden variations
of slope or curvature.
[0085] The surface of the second intrados side 6 is formed by the setting side-by-side of
the second faces 1 b of the formworks 1, arranged side-by-side to each other and in
sequence.
[0086] It has to be noted that the making method according to the present disclosure allows,
thank to the designing and the custom making of the individual formworks 1, to obtain
said intrados 6 with a curved, continuous and precisely and evenly jointed surface
between adjacent formworks 1.
[0087] Figure 8 shows a phase of positioning a reinforcement 8 in the recesses 2 of the
plurality of formworks 1.
[0088] In particular, the reinforcement 8 comprises longitudinal reinforcements or bars
10 which are arranged along said channel 29, i.e. substantially parallel to the direction
150 of ascent or descent of the stairway 100; the reinforcement 8 further comprises
transversal reinforcements or bars 11 arranged substantially perpendicular to the
longitudinal reinforcements 10 and substantially parallel to a treadable plane 12,
i.e. parallel to the first faces 1 a of the formworks 1.
[0089] It has to be noted that the transversal bars 11 can, e.g., be positioned in the internal
recess 2 by slipping them through suitable through holes (not shown) made in the side
faces 1f, 1g and in the partition 25 of the respective formwork 1.
[0090] In the embodiment shown, the longitudinal reinforcements 10 extend for a stairway
section 100 comprising a plurality of steps 110, even all of the steps 110; in other
words, each longitudinal reinforcement 10 is common to a plurality of adjacent formworks
1, in order to strengthen the connection between the formworks 1 themselves.
[0091] Figure 9 shows in detail the positioning of the reinforcement 8 in the recesses 2.
It has to be noted that the transversal reinforcements 11 are interconnected with
the longitudinal reinforcements 10 by a phase of hooping which includes the use of
hoops 15 surrounding and clasping the intersection regions between the longitudinal
reinforcements 10 and the transversal reinforcements 11.
[0092] Moreover, the hooping is also made between the transversal reinforcements 11 of a
formwork 1 and the transversal reinforcements 11a of an adjacent formwork; this is
illustrated by way of example in Figure 9, in which hoops 15b are shown connecting
a transversal bar 11 of the formwork 1 to a transversal bar 11 a of the adjacent formwork
5 (not shown). This allows to strengthen the connection between the adjacent formworks
1,5.
[0093] The reinforcement 8 is made, e.g., by means of metal bars, as those customarily used
in the building field to reinforce concrete.
[0094] Referring to Figure 10, it is illustrated a phase of filling the formworks 1 with
a filler material, which in the example is concrete 40.
[0095] Basically, once the formworks 1 have been assembled and joined to each other, and
the longitudinal reinforcement 10 and the transversal reinforcements 11 have been
arranged in the internal recesses 2 and the hooping has been made between them, fluid-state
concrete 40 is cast into the internal recesses 2, completely filling them. Concrete
40 is cast into the internal recesses 2 through the openings 21 on the first faces
1a of the formworks 1. The presence of the openings 23, 24 aligned to each other facilitates
the homogeneous distribution of the concrete 40 in the recesses 2, also allowing the
transit of concrete 40 from one formwork 1 to another one and the creation of a continuous
structure involving all formworks 1.
[0096] E.g., the filling of each formwork 1 may be carried out by casting the concrete 40
through the openings 21 of the formwork 1 at the higher level (i.e. nearer to the
top floor 13), so that the concrete 40 may flow down along the channels 29 and fill
all of the underlying formworks 1. In this case the filling of each formwork 1 is
carried out by a single casting operation of concrete 40.
[0097] Alternatively, the concrete 40 may be cast in sequence into each formwork 1, one
after the other.
[0098] When the concrete 40 has dried up, the stairway 100 is structurally complete. Of
course, finishing operations will be possible, like, e.g., laying of marble or stone
slabs, or of wooden boards on the first treadable faces 1a, polishing of the surfaces
in sight, plastering, painting.
[0099] From the present description it is evident that the formworks 1 remain permanently
included in the structure of the stairway 100; in fact, the formworks 1 are disposable
formworks, making up a skeleton 7 having both a load-bearing structural function for
the stairway 100 and a containing function for the concrete 40. The concrete 40 turns
the stairway 100 into a single body, carrying out the final locking of the formworks
1 to each other. The reinforcement 8 has a structural reinforcing function, among
which that of enhancing joining solidity between the formworks 1.
[0100] Therefore, the stairway 100 has a plurality of steps 110, each comprising a respective
formwork 1 and the filler material (in the example, concrete 40) which is permanently
included in the formwork 1 itself.
[0101] Each step 110 has a treadable region 12 corresponding to the first face 1 a of the
formwork 1, a riser 65 corresponding to the riser face 1 e of the formwork 1, an intrados
6 corresponding to the second face 1b of the formwork 1, and sides 66, 67 corresponding
to the side faces 1f, 1g of the formwork 1.
[0102] In alternative embodiments, the formwork is designed and made so as to correspond
to a plurality of consecutive steps 110 of the stairway 100, instead of to a single
step 110. Basically, the overall number of distinct formworks to be made may be lower
than the total number of steps 110, as two or more successive steps may be comprised
in a single formwork. In pratice, in accordance with these variant embodiments, the
wording "wherein each formwork (1, 5) has a shape corresponding to a respective step
(110) of the stairway (100)" in claim 1 and in claim 17 is to be understood in the
sense that the formwork has dimension corresponding to a plurality of subsequent steps
of the final stairway. It follows that, in accordance with these variant embodiments,
the number of steps that are made together with a single formwork is established during
the designing and computing phase.
[0103] The subject of the present disclosure has hereto been described with reference to
preferred embodiments thereof. It is understood that other embodiments might exist,
all falling within the concept of the same invention, as defined by the protective
scope of the claims hereinafter.
1. A method for making a stairway (100), said method comprising the phases of:
- prearranging a plurality of blocks (16);
- shaping each of said blocks (16) to the obtainment of a plurality of formworks (1,
5), wherein each formwork (1, 5) has a shape corresponding to a respective step (110)
of the stairway (100);
- joining said formworks (1, 5) in sequence;
- filling each of said formworks (1, 5) with a filler material (40), to the obtainment
of a respective step (110) comprising said formwork (1, 5) and said filler material
(40) permanently included in said formwork (1, 5),
characterised in that
the method comprises a design phase which includes a custom computing of the dimensions
and shape of each of said formworks (1, 5) on the basis of the dimensions of an installation
site of the stairway (100), wherein said phase of shaping each of said blocks (16)
is based on said design phase.
2. The method according to claim 1, wherein said formworks (1, 5) are joined by a phase
of on-site assembling, wherein said formworks (1, 5) are arranged adjacent and aligned
in a preset sequence along a direction (150) of ascent-descent of said stairway (100),
each formwork (1, 5) comprising a first face (1a) corresponding to a treadable region
(12) of the respective step (110) and a second face (1b) opposite to the first face
(1a) and having a curved surface, said design phase being such that in said assembling
phase the second faces (1 b) of the adjacent formworks (1, 5) are arranged side-by-side
to each other, to form a continuous even surface (6).
3. The method according to claim 1 or 2, wherein said phase of joining the formworks
(1, 5) provides a joining between adjacent formworks (1, 5) by connecting means (3,
4) adapted to make a tongue-and-groove coupling between two adjacent formworks (1,
5).
4. The method according to claim 1, 2 or 3, wherein said blocks (16) are made of wood-concrete
or of polystyrene.
5. A method according to any one of the claims 1 to 4, wherein said phase of shaping
each of said blocks (16) comprises a material-removal manufacturing.
6. The method according to claim 5, wherein said phase of shaping each of said blocks
(16) is carried out by a milling machine (17) or by a laser cutting machine or a hydrojet
cutting machine.
7. The method according to any one of the claims 4 to 6, wherein said blocks (16) are
made of polystyrene and wherein the phase of shaping the block (16) is followed by
a phase of coating the respective formwork (1, 5) by a hardening resin.
8. The method according to any one of the claims 1 to 7, wherein each of said formworks
(1, 5) has a substantially prismatic shape having an internal recess (2), and wherein
each of said formworks (1, 5) has a third face (1c) and a fourth face (1d) which are
intended to face respective adjacent formworks (5, 1), said third face (1 c) and fourth
face (1d) having access openings (23, 24) for accessing said internal recess (2).
9. The method according to claims 2 and 8, wherein during said assembling phase the formworks
(1, 5) are arranged so that the access openings (23, 24) of said third face (1 c)
and fourth face (1 d) of adjacent formworks (1, 5) be aligned to each other to form
a channel (29) extending along said direction (150) of ascent-descent.
10. The method according to claim 9, comprising a phase of positioning a reinforcement
(8) into said internal recesses (2), said reinforcement (8) comprising longitudinal
reinforcements (10) arranged along said channel (29).
11. The method according to claim 10, wherein said reinforcement (8) comprises transversal
reinforcements (11) that are substantially parallel to a first treadable face (1a)
of the respective formwork (1, 5) and substantially perpendicular to said longitudinal
reinforcements (10).
12. The method according to claim 11, comprising a phase of hooping by hoops (15b) between
transversal reinforcements (11) of adjacent formworks (1, 5).
13. The method according to any one of claims 8 to 12, wherein the phase of filling said
formworks (1, 5) includes a phase of concrete casting (40) into said internal recesses
(2).
14. A stairway (100) including a plurality of steps (110), wherein each step (110) comprises
a formwork (1, 5) and a filler material (40) permanently included in said formwork
(1, 5),
characterised in that
said stairway (100) has a first treadable side (12) and a second intrados side (6)
opposite to said first treadable side (12), said second intrados side (6) being a
continuous even surface, wherein each of said formworks (1, 5) has a first treadable
face (1 a) and a second face (1 b) opposite to the first treadable face (1 a) and
corresponding to a respective portion of said second intrados side (6), said continuous
even surface (6) being formed by the arranging side-by-side of said second faces (1
b) of the formworks (1, 5).
15. The stairway (100) according to claim 14, wherein said formworks (1, 5) are made of
wood-concrete or of polystyrene.
16. The stairway (100) according to claim 15, wherein said formworks (1, 5) comprise a
core of polystyrene and an external coating of polyurethane resin or of fiberglass.
17. An apparatus for making a plurality of formworks (1, 5), wherein each formwork (1,
5) has a shape corresponding to a respective step (110) of a stairway (100), said
apparatus comprising a computer (18) and a shaping machine tool (17),
characterised in that
the computer (18) is configured for inputting data related to dimensions of an installation
site of the stairway (100) and is further configured for executing a custom computing
software for each of said formworks (1, 5) on the basis of said dimensions of the
installation site, and in that the shaping machine tool (17) is configured for shaping a plurality of blocks (16)
on the basis of the results of such custom computing, to the obtainment of said plurality
of formworks (1, 5).