ES2626171T3 - Formwork and associated flooring - Google Patents

Abstract

Formwork (1) for mixed steel-concrete floor comprising a self-supporting profile (2) comprising at least one upper central area (3), lateral souls (4, 4 ') that extend said upper central area on either side from this and towards the bottom and at least two lower bases (5, 5 ') that extend said lateral souls, said formwork being characterized in that it further comprises a separator profile (10) comprising at least one upper tray (11) and two lateral wings (12, 12 ') extending said upper tray on either side of it and downwards, said separator profile being arranged at least by means of the end of said lateral wings on the upper part of said self-supporting profile intended to work in compression, the boundary between the part destined to work in compression and the part destined to work in traction being located about half the height of the lateral core of said self-supporting profile, so that it covers at least partially said upper central area and thus forms at least one caseton (15) that minimizes the amount of concrete needed.

Description

DESCRIPTION

Formwork and associated flooring

[0001] The present invention relates to a formwork intended for the construction of mixed soils of

steel-concrete by casting a concrete slab over the formwork.

[0002] It is known, in the field of construction, to resort to metal formwork to facilitate the manufacture of floors. These formwork, consisting of a metal sheet generally formed by profiling, are

10 arranged, through its extremities, on the structure of the building that is under construction and retain the cast concrete until it dries and forms the floor slab.

[0003] Depending on the formwork form, the soil obtained can be of 3 different natures: lost, additive or collaborating formwork. Lost formwork floor means that only concrete contributes to the

15 mechanical resistance of the ground. By additive soil it is understood that the mechanical resistance of the soil is the sum of the respective strengths of the formwork and the concrete. Finally, by collaborating soil it is understood that the resistance of the soil is greater than the sum of the respective strengths of the formwork and the concrete.

[0004] During the construction phase, the metal formwork must support the sum of the weight of concrete and 20 of its own weight without depletion or deviation too important, whether or not it has been used to props

provisional arranged at regular intervals between the walls of soil contention.

[0005] In addition, after the removal of the possible provisional struts and during the land use phase, referred to as the mixed phase term, the soil should not deviate too much under normal conditions of use.

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[0006] These construction requirements in fact limit the current scope of mixed steel-concrete soils to approximately 5 meters. In fact, since the reach of the soil is proportional to its thickness, the addition of concrete is necessary to increase the thickness of the soil and therefore its reach. However, the metal formwork cannot withstand this addition.

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[0007] To increase the reach of mixed steel-concrete floors, document US5,205,098 discloses the increase in structural strength of the formwork by combining two metal profiles arranged inverted and fixed to each other by means of their bases. Unfortunately, this solution significantly increases the thickness of the floor and the presence of the lower profile makes the placement of the formwork in the building structure

35 delicate.

[0008] In addition, document US4,697,399 discloses the obturation of the wave passages of the ribbed sheets used as formwork to prevent them from being filled with the concrete. This solution allows to increase the height of the wave passages so that the resistance of the soil increases without increasing the amount of concrete

40 needed. Then it is possible to either increase the reach of the soil or minimize the thickness of the concrete located above the wave passages. Unfortunately, such a solution cannot be raised to obtain long ranges, for which the combined presence of concrete and reinforcing reinforcement bars in the wave passages is necessary to guarantee the resistance to soil traction.

[0009] GB1469478 also discloses a formwork for mixed steel-concrete flooring.

according to the preamble of revindication 1.

[0010] The present invention aims to remedy the aforementioned problems by proposing a formwork that allows to minimize the amount of concrete needed while still maintaining a resistance

50 mixed soil mechanics sufficient to increase its reach beyond 8 meters.

[0011] For these purposes, the first object of the invention is a formwork for mixed steel-concrete floors comprising:

55 - a self-supporting profile comprising at least one upper central zone, lateral souls that extend the upper central zone on either side of it downwards and at least two lower bases that extend the lateral souls;

- a separator profile comprising at least one upper tray and two lateral wings that extend the upper tray on either side of it and down;

The separating profile is arranged at least by the end of the lateral wings on the upper part of the self-supporting profile intended to work in compression, the limit between the part destined to work in compression and the part destined to work in traction is located in the vicinity half the height of the lateral core of said self-supporting profile, so that it covers at least partially the upper central area and so! form at least one caseton that minimizes the amount of concrete needed.

[0012] The formwork according to the invention may also comprise the following optional features, taken in isolation or in combination:

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- the separating profile covers the entire upper central area;

- the lateral souls are inclined towards the outside of the upper central area;

- each of the lateral souls has a longitudinal tensioner consisting of two folds that form a step of the lateral soul;

15 - the lateral wings are inclined towards the outside of the upper tray;

- the tip of the lateral wings has a raised edge;

- the raised edge rests on the longitudinal tensioner, the separating profile and the self-supporting profile being integral by sewing by means of fixations regularly distributed over the length of the raised edge;

- the extremity of the lateral wings involves a Z-shaped step;

20 - the step rests on two extremities of the upper central area;

- the self-supporting profile comprises two upper central areas;

- the self-supporting profile covers at least partially the two upper central areas.

[0013] A second object of the invention is constituted by a method of manufacturing a formwork for mixed steel-concrete floor comprising the steps according to which:

- a self-supporting profile is provided comprising at least one upper central zone, lateral souls that extend the upper central zone on either side of it and downward and at least two lower bases that extend the lateral souls;

30 - a separating profile is provided comprising at least one upper tray and two lateral wings that extend the upper tray on either side of it and down;

- at least the end of the lateral wings of the separating profile is disposed on the upper part of the self-supporting profile intended to work in compression, the limit between the part intended to work in compression and the part destined to work in tension being located around the half the height of the lateral soul of said

35 self-supporting profile, so that it covers at least partially the upper central area and so! form at least one caseton that minimizes the amount of concrete needed;

- the self-supporting profile and the separating profile are secured by means of fixations located along the end of the lateral wings.

[0014] A third object of the invention is constituted by a kit for manufacturing a floor formwork

mixed steel-concrete comprising:

- at least one self-supporting profile comprising at least one upper central zone, lateral souls that extend the upper central zone on either side of it downwards and at least two lower bases that extend the

45 lateral souls;

- at least one separator profile comprising at least one upper tray and two lateral wings that extend the upper tray on either side of it and down.

[0015] A fourth object of the invention is constituted by a mixed steel-concrete floor comprising at least one formwork according to the invention and a slab of cast concrete on the formwork.

[0016] A fifth object of the invention is constituted by a procedure of a mixed steel-concrete floor of a building comprising the stages according to which:

55 - self-supporting profiles are provided comprising at least one upper central zone, lateral souls that extend the upper central zone on either side of it downwards and at least two lower bases that extend the lateral souls;

- separating profiles are provided comprising at least one upper tray and two lateral wings that extend the upper tray on either side of it and down;

- juxtaposed self-supporting profiles on a building structure;

- at least the end of the lateral wings of the separator profiles is arranged on the upper part intended to work in compression of at least some of the self-supporting profiles, the limit between the part destined to work in compression and the part destined to work in traction being located around the middle

5 of the height of the lateral core of said self-supporting profile, so that it covers at least partially at least one of the upper central areas and so! form at least one caseton that minimizes the amount of concrete needed;

- each of the self-supporting profiles and the separating profile in which it is arranged by means of fasteners located along the end of the lateral wings, so as to form a formwork;

10 - reinforcing reinforcement bars are arranged in the wave passages formed by the lateral souls of two successive self-supporting profiles;

- the liquid concrete is poured over the entire surface formed by the formwork and the self-supporting profiles.

[0017] Other features, aspects and advantages of the present invention will appear upon reading the

description that follows.

[0018] The invention will be better understood after reading the description that follows, given by way of explanation.

and not limiting, in reference to the attached figures that represent:

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- Figure 1 represents a cross section of a first formwork example according to the invention;

- Figure 2 represents a cross-section of a second formwork example according to the invention;

- Figure 3 represents an exploded view of a mixed steel-concrete floor according to the invention.

[0019] The same reference numbers represent the same elements in each of the figures.

[0020] Within the framework of the invention, the different constituent elements of the formwork are preferably made of metal such as bare steel or galvanized by means of a zinc alloy. Optionally, the steel, galvanized or not, will be coated with a coat of paint to better protect it from corrosion. At least one

30 of the constituent elements of the formwork, and in particular the separating profile, could however be of plastic or any other material sufficiently resistant to the use to which the element is intended.

[0021] When the concrete is poured into a formwork, the constituent profiles of the formwork are subjected to bending stresses so that the upper parts of the profiles are subjected to stresses of

35 compression and the lower parts of the tensile tension profiles, specifically in the longitudinal direction. The relative importance of the areas subject to traction and the areas subject to compression depends on different geometric parameters such as the height of the souls, the thickness of the concrete layer, the length, the width of the profiles. The person skilled in the art knows how to determine from these parameters which is the relative distribution of the areas subjected to traction and of the areas subjected to compression. As a general rule, the limit 40 between the area subjected to traction and the area subject to compression is located about half the height of the lateral core of the profile.

[0022] An example formwork according to the invention is described in reference to Figure 1.

[0023] First, the formwork 1 comprises a self-supporting profile 2. By self-supporting profile,

It understands a sheet shaped so that simply the rigidity of this form guarantees its stability and allows its placement on the structure of the building under construction through its extremities. The forms that this self-supporting profile can take are known. Preferably, a form that allows the manufacture of an additive soil will be chosen. In general, the self-supporting profile comprises at least one horizontal upper central zone 50 that extends in the longitudinal direction of the self-supporting profile, two lateral souls 4 and 4 'that extend the upper central zone 3 to one and the other side of this and down and at least two lower 5 and 5 'horizontal bases that extend the lateral souls.

[0024] In the case of this example, the upper central area 3 also comprises two longitudinal ribs 6 and 6 'separated by a transverse notch 7. This forming increases the stiffness of the area

central superior 3 and ace! makes possible the circulation of workers on this surface.

[0025] In the case of this example, the lateral souls 4 and 4 'are inclined, extending downwards and outwards from the upper central area. Alternatively, they can extend vertically or towards the

interior, depending on the stiffness sought from the self-supporting profile. Each lateral core of this example also includes a longitudinal tensioner 8, 8 'consisting of two folds that form a slight step in the part of the lateral core subjected to compression stresses during the mixed phase. This longitudinal tensioner, on the one hand, improves the mechanical behavior of the self-supporting profile and, on the other, favors the placement of a separator profile as will be seen later. Alternatively or complementary, the lateral souls 4 and 4 'may present concrete anchoring areas as projections or notches located in the part of the lateral core subjected to tensile stresses.

[0026] In the case of this example, the lower bases 5 and 5 'have a raised edge 9, 9' that functions as a tensioner and facilitates the placement of the formwork in particular making the joints between two profiles

adjacent self-supporting be more tight to liquid concrete.

[0027] As a general rule, the self-supporting profile has a height between 150 and 300 mm, the example of Figure 1 has been made with a self-supporting profile 220 mm high.

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[0028] Secondly, the formwork 1 comprises a separating profile 10. The latter comprises a horizontal upper tray 11 extending in the longitudinal direction of the separating profile and two lateral wings 12, 12 'extending the upper tray 11 to one and another side of this and down.

[0029] In the case of this example, the upper tray 11 also comprises a transverse notch 13.

This forming increases the rigidity of the upper tray 11 and so! makes possible the movement of workers on this surface. Alternatively or complementary, the upper tray 11 may have longitudinal ribs or concrete anchoring areas as projections or notches.

[0030] In the case of this example, the lateral souls 12 and 12 'are inclined, extending downwards and

towards the outside of the upper tray 11. Alternatively, they can extend vertically or inwards, depending on the stiffness sought. Each side wing of this example is flat and has, at its tip, a raised edge 14, 14 'that functions as a tensioner and facilitates the placement of the separator profile 10 on the self-supporting profile 2.

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[0031] As a general rule, the separator profile has a height between 80 and 250 mm, the example of Figure 1 has been made with a 150 mm high separator profile.

[0032] The width of the upper tray 11, the angle of inclination of the lateral wings 12, 12 'with respect to the upper tray 11 and the length of the lateral wings are adjusted so that the spacer profile 10 can be

arranged by the end of its lateral wings 12, 12 'on the part of the self-supporting profile 2 intended to work in compression so as to cover at least partially its upper central area 3 at the same time as forming a caseton 15 between the latter and the tray upper 11 of the separating profile 10. Said fitting of the separating profile on the part of the self-supporting profile intended to work in compression offers several advantages:

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- increases the inertia of the formwork and optimizes the distribution of loads on the formwork;

- facilitates the further solidarity of the two profiles by facilitating access to the socket;

- on the underside of the self-supporting profile, solidarity is not very visible and is arranged in areas that do not disturb;

45 - steel consumption is minimized.

[0033] In the case of this example, the raised edge 14 (respectively 14 ') of the side wing of the separator profile is fitted on the self-supporting profile and supported on the longitudinal tensioner 8 (respectively 8') of this. The two profiles are preferably joined by sewing, preferably by means of fasteners 16, as by

50 example screws or rivets, regularly distributed over the length of the raised edge 14, 14 '.

[0034] As a general rule, the number of fixations is limited to shorten the manufacturing time of the soil. Sewing in that case is not enough for the separator profile to participate in the mechanical strength of the mixed soil assembly. The separating profile in that case is lost formwork. However, it can be advantageously

55 improve the mechanical resistance of the soil by multiplying the number of fixings, which nevertheless lengthens the manufacturing time of the soil. Therefore, a compromise must be found between the desired mechanical resistance of the soil and the time spent sewing the separator profile to the self-supporting profile. Sewing can be done on site or alternatively at the factory before delivering the formwork on site.

[0035] In the case of this example, caseton 15 has been left empty. Alternatively, it can be filled with thermal and / or acoustic insulation and / or receive the electrical networks and / or the fluid networks of the building under construction.

[0036] Next, a second formwork example will be described according to the invention in reference to Figure 2. This second example takes up all the characteristics of the example described in reference to Figure

1 with the exception of the differences mentioned below.

[0037] This second formwork 1 differs from the formwork illustrated in Figure 1 mainly because the self-supporting profile 2 comprises two upper central areas 3 and because the separator profile 10 covers them.

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[0038] In the case of this example, the upper tray 11 of the separator profile comprises a transverse scallop 13 and longitudinal ribs 17, 17 'that function as tensioners. The lateral wings 12, 12 'are inclined, extending towards the bottom and towards the outside of the upper tray 11. Each lateral wing of this example involves longitudinal tensioners 18, 18' constituted by folds that form a slight step in the wing

15 lateral. The end of each side wing is formed by a Z-shaped step 19, 19 'that functions as a tensioner and facilitates the placement of the separator profile 10 on the self-supporting profile 2.

[0039] In the case of this example, the step 19 (respectively 19 ') of the end of the lateral wing rests on the tip 20 of the first upper central area of the self-supporting profile 2 (respectively on the

20 limb 20 'of the second upper central zone). The two profiles are secured by sewing, preferably by means of fasteners 16, such as screws or rivets, regularly distributed over the length of step 19, 19 '.

[0040] As a complement to the examples illustrated in Figures 1 and 2, it is observed that the fitting mode 25 of the spacer profile on the self-supporting profile by step 19, 19 ', as illustrated in Figure 2, may

be applied in the example of figure 1 instead of the engagement mode by means of the raised edge 14, 14 'and reciprocally. It is also observed that the separator profile can take various forms. Its upper tray may, for example, have ribs so that several cases 15 are formed between the separator profile and the self-supporting profile.

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[0041] The mixed steel-concrete floor is made by the juxtaposition of formwork 1 on the structure 21 of the building under construction as illustrated in Figure 3. Depending on the lightening of the concrete sought, the formwork 1 may immediately be adjacent to others, as illustrated in Figure 3, or interleaved between self-supporting profiles 2 that are not provided with a separator profile 10. They are then arranged

35 reinforcing reinforcement bars 22 in wave passages 23 formed by the lateral souls of two successive self-supporting profiles 2. The liquid concrete is then poured over the entire surface formed by the formwork 1 and the possible self-supporting profiles 2, so that they form a slab 24.

[0042] Preferably, the distance between the upper part of the surface separating profiles of the slab will be at least 20 mm to ensure good compressive strength of the slab. However it will happen

preference at distances of the order of 50 to 200 mm to allow the coating with possible anti-crack reinforcements 25 or to allow the structure supporting the mixed floor to work mainly in traction or even to increase fire resistance.

[0043] As seen in Figure 3, the boxes 15 formed by the boxing of the profiles

separators 10 on the self-supporting profiles 2 allow to minimize the amount of concrete necessary for the slab formation. Ace! It is possible to make floors of greater length.

[0044] The presence of cassettes 15 does not alter the mechanical resistance of the ground formed. In fact, only 50 part of the slab located above the separator profiles guarantees compressive strength, while

that the combination of reinforcing reinforcement bars and concrete placed in wave passages 23 guarantees tensile strength.

[0045] In general, the shape and dimensions of the cassettes will be adjusted according to the 55 circumstances to obtain the best compromise between the desired mechanical strength and reach of the ground.

mixed.

[0046] The separator profile can be as! have a width less than the width of the upper central area of the self-supporting profile so that it only partially covers the upper central area when arranged by the

extremity of its lateral wings on the self-supporting profile. Such configuration may be appropriate when it is not strongly sought to lighten the mixed soil. However, and for these same reasons of lightening the ground, the configuration in which the separating profile covers the integrality of at least one upper central area will be preferred so that one of the sides of the caseton is formed at least by the integrality of this upper central zone 5 (except with the eventual localized support of step 19, 19 'on the tip 20, 20' of the upper central area).

[0047] For these same reasons of lightening the ground, the ratio between the height of the separating profile and the height of the self-supporting profile will preferably vary between 0.35 and 1. In particular, the combination of a height

10 of self-supporting profile between 150 and 300 mm and the proportion between 0.35 and 1 allows to obtain a formwork that presents the best optimal point in terms of inertia and lightening.

[0048] The digital simulations carried out specifically with the formwork illustrated in Figures 1 and 2 have shown that the invention allows reaching ranges of 8 meters and more than 12 meters.

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[0049] This combination of a self-supporting profile and a separator profile has several advantages:

- the use of a separating profile other than the self-supporting profile allows the use of self-supporting profiles that already exist;

- the profiles are made from sheet coils of limited width (and generally of the order of 1200 20 to 1500 mm), the use of the different separating profile also prevents the formwork from being made from a

only higher profile but too narrow, the increase in the height of the lateral soul leading, in fact, to the reduction of the width of the upper central area;

- the use of the different separating profile allows to avoid a concrete overload that generates a formwork made of a single higher profile. In fact, reducing the width of the upper central area has the effect of bringing

25 formwork to each other, multiply the number of wave passages, increase the amounts of concrete needed to fill them and therefore increase the weight of the global concrete.

Claims (11)

I. Formwork (1) for mixed steel-concrete floor comprising a self-supporting profile (2) comprising at least one upper central area (3), lateral souls (4, 4 ') that extend said upper central area 5 on either side of it and towards the bottom and at least two lower bases (5, 5 ') that extend said lateral souls, said formwork being characterized in that it also comprises a separator profile (10) comprising at least one tray upper (11) and two lateral wings (12, 12 ') extending said upper tray on either side of it and down, said separating profile being arranged at least by means of the end of said lateral wings on the upper part of said self-supporting profile intended to work in compression, the limit 10 between the part intended to work in compression and the part intended to work in traction being located about half the height of the lateral core of said self-supporting profile, so that it covers at least partially said upper central area and so! form at least one caseton (15) that minimizes the amount of concrete needed. 15 2. Formwork (1) according to claim 1 wherein said separator profile (10) covers all of the said upper central area (3). 3. Formwork (1) according to any one of the preceding claims wherein said lateral souls (4, 4 ') are inclined towards the outside of said upper central area (3). twenty 4. Formwork (1) according to any one of the preceding claims in which each of said lateral souls (4, 4 ') comprises a longitudinal tensioner (8, 8') constituted by two folds that form a step of said lateral core. 5. Formwork (1) according to any of the preceding claims wherein said side wings (12, 12 ') are inclined towards the outside of said upper tray (11). 6. Formwork (1) according to any of the preceding claims wherein said end of the side wings (12, 12 ') has a raised edge (14, 14'). 30 7. Formwork (1) according to claims 4 and 6 wherein said raised edge (14, 14 ') rests on said longitudinal tensioner (8, 8'), said separating profile and said self-supporting profile being joined by sewing by means of fixations (16) regularly spread over the length of the raised edge (14, 14 '). Formwork (1) according to any one of claims 1 to 5 wherein said wing tip lateral (12, 12 ') involves a Z-shaped step (19, 19'). 9. Formwork (1) according to claim 8 wherein said step (19, 19 ') is supported on the extremities (20, 20') of said upper central area. 40 10. Formwork (1) according to any of the preceding claims wherein said self-supporting profile (2) comprises two upper central areas (3). II. Formwork (1) according to claim 10 wherein said self-supporting profile (10) partially covers at least said two upper central areas (3). 12. Method of manufacturing a formwork (1) for mixed steel-concrete floor comprising the stages according to which: 50 - a self-supporting profile (2) is supplied, which comprises at least one upper central area (3), lateral souls (4, 4 ') that extend said upper central area on either side of it and down and at least two lower bases (5, 5 ') that extend said lateral souls; - a separator profile (10) is provided comprising at least one upper tray (11) and two lateral wings (12, 12 ') extending said upper tray on either side of it and down; 55 - at least the end of said lateral wings (12, 12 ') of the separating profile is arranged on the upper part of the self-supporting profile (2) intended to work in compression, the limit between the part intended to work in compression and the part destined to work in traction being located about half the height of the lateral core of said self-supporting profile, so that it covers at least partially said upper central area and thus! form at least one caseton (15) that allows to minimize the amount of concrete needed; - said self-supporting profile and said separating profile are secured by means of fasteners located along the end of said lateral wings. 13. Formwork manufacturing kit (1) for mixed steel-concrete floor according to any of the 5 claims 1 to 11 comprising: - at least one self-supporting profile (2) comprising at least one upper central area (3), lateral souls (4, 4 ') that extend said upper central area on either side of it and down and at least two bases lower (5, 5 ') that extend said lateral souls; - 10 - at least one separator profile (10) comprising at least one upper tray (11) and two lateral wings (12, 12 ') that extend said upper tray on either side of it and down. 14. A mixed steel-concrete floor comprising at least one formwork according to any one of claims 1 to 11 and a concrete slab (24) poured onto said formwork. fifteen 15. Procedure for manufacturing a mixed steel-concrete floor of a building comprising the stages according to which: - self-supporting profiles (2) are provided comprising at least one upper central zone (3), lateral souls 20 (4, 4 ') that extend said central zone to either side of it and down and at least two lower bases (5, 5 ') extending said lateral souls; - separator profiles (10) are provided comprising at least one upper tray (11) and two lateral wings (12, 12 ') that extend said upper tray on either side of it and down; - said self-supporting profiles are juxtaposed on a structure (21) of said building; 25 - at least the end of the lateral wings (12, 12 ') of the separator profiles is arranged on the upper part intended to work in compression of at least some of the self-supporting profiles, the limit between the part intended to work in compression and the part destined to work in traction being located about half the height of the lateral core of said self-supporting profile, so that it covers at least partially at least one of said upper central areas and so! form at least one caseton (15) that allows to minimize the amount of concrete needed; - each of said self-supporting profiles is joined to said separating profile on which it is arranged by means of fasteners located along the end of said lateral wings, so that it forms a formwork (one); - the reinforcement reinforcement bars (22) are arranged in the wave passages (23) formed by said lateral souls 35 of two successive self-supporting profiles; - the liquid concrete is poured over the entire surface formed by said formwork and said self-supporting profiles.