ES2918018A1 - Recoverable roof formwork and recovery procedure (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Recoverable roof formwork system used for the formation of flat concrete elements, based on the arrangement of multiple beams on which a plurality of boards (2) that transmit to strips willing vertically willing the weight of the weight of vertically The concrete elements, having the boards (2) a length between 1.9 and 2.5 meters, consisting of the formwork system in a plurality of belts (1) arranged in alignments that are separated from each other and a plurality of portacorreas (3), which act as a means of support of the formwork boards. The belts (1) arranged in the opposite edges of the boards have a cross section that has an outstanding central part upwards from which two inclined lateral sections are laterally extended that extend in a descending direction, such that the boards They rest on these inclined sections. This system requires fewer construction elements and therefore also a shorter assembly and disassembly time to encourage a flat concrete surface. (Machine-translation by Google Translate, not legally binding)

Description

DESCRIPTION

Retrievable Roof Formwork System and Retrieval Procedure

OBJECT OF THE INVENTION

The purpose of this application is to register a recoverable ceiling formwork system that is used for the formation of flat surfaces from the construction of concrete elements, as well as a recovery procedure intended to recover the elements used in the formwork system.

More specifically, the invention proposes the development of a recoverable formwork system that requires the use of a smaller number of construction elements and therefore also a shorter assembly and disassembly time for the formwork of a flat concrete surface.

FIELD OF THE INVENTION

This invention has its application within the construction sector and more specifically within the sector dedicated to the manufacture and use of formwork.

BACKGROUND OF THE INVENTION

Formwork systems for concrete slabs of the type consisting of a first level of support straps, which have no structural function, with recesses on their upper face to set the distance between the alignments of beams on the upper level or straps arranged in a substantially perpendicular direction are known. to the strap holders, which act as a support for the formwork boards and on which the concrete is poured.

After the concrete is poured, the process of setting and hardening begins. It is common for this process to require, under normal conditions, approximately one week for the concrete to acquire sufficient strength for the executed slab to be able to support its own weight, without generating structural problems, supported by the structure of the building.

When constructing multi-storey buildings, a first option is to wait for the hardening of the concrete to allow the stripping of the entire slab, re-shore it and use the formwork again on the next floor. The load-bearing capacity of the slabs usually means that at least two propped-up floors are required under the formwork floor to support the weight of the fresh concrete. Another option to advance more quickly in the construction of the building is to leave two more floors with formwork under which concrete must be poured. This last solution implies the use of triple formwork than in the case of total stripping and re-shoring.

If it is desired to recover the elements used for the formwork for use in the construction of the next floor, formwork systems that allow early recovery must be used.

These systems allow the partial or total disassembly of the formwork at an early stage of the curing of the concrete. In general, they offer the possibility of leaving the slab propped up with spans between supports that do not exceed 2.5 metres. This allows, in many cases from the third day, to use the dismantled material in the following floors with the saving of elements for the formwork that this entails. Depending on the type of morphology of each system, it may be necessary to change the position of the struts (repropping) during the early recovery process.

It is worth mentioning that, in some of these systems, at least part of the purlins that are responsible for supporting the ends of the formwork boards have a specific profile such that their upper end is substantially flush with the upper face of the boards. formwork and are provided with projections on the side faces to support the ends of the boards. Said lateral projections have a slope with respect to the horizontal plane intended to allow the tilting and removal of the boards without the need to separate the beam from the ceiling.

The utility model no. ES101500U is known, which shows a system where all the belts are of the mentioned type and in which alignments of alternate beams are removed to allow the tilting and exit of the boards. The purlin alignments are lowering the slab and the distance between them must not exceed 2.5 meters. However, the maximum dimension of the decks is limited to approximately half the length of the maximum span between shoring slabs at the time of anticipated recovery.

This limitation in the maximum dimension of the boards is a significant drawback since the difference between large-format boards (around 2m long) and small-format ones that are one meter long is relevant in terms of performance.

In this way, large format boards have the following advantages:

• They increase the speed of assembly since half the number of boards per square meter of ceiling are installed;

• They offer a good surface finish of the ceiling since there are half the number of joints between boards. In addition, using the same number of purlin alignments (approximately 1 meter apart), the large-format boards are supported in their central area and reduce deflection under the same load. Specifically, a board with a length of 1m has a deflection 227% higher than that of a board of almost 2m with the same thickness and subjected to the same load.

• They reduce the need for nailing to stabilize the boards by up to 75%, since they can be nailed on the strap that they have under their central area, thus facilitating subsequent unnailing. In the case of small-format boards (1 meter), they must be nailed at their extreme supports on the wings of the purlins, which makes it difficult to recover them and can cause damage to the wooden boards.

To use decks with dimensions close to the maximum span between slab shoring after early recovery, an alternate combination of purlin alignments provided with lateral projections with a slope is used to allow the deck to be tilted and removed, without the need to separate the beam. of the ceiling and other alignments of beams that incorporate removable intermediate support elements for the decks that can be removed for dismantling the decks without moving the beams. An example of embodiment of this type of formwork is shown in document no. ES2264296A1 of the same applicant as the present application. In this case, the removable intermediate support elements must be mounted on the straps that equip them and subsequently removed, entailing greater complexity and expense in materials, as well as in labor.

The systems described in documents no. ES101500U and ES2264296A1 leave alignments of purlins on the props that remain supporting the floor after early recovery of the formwork. This means that, with the current rates of progress of the construction works, it is necessary to provide, in addition to the material necessary to form the desired area, an additional number of purlins that will remain temporarily immobilized in the two or three floors that require shoring.

To reduce the cost of the immobilized material on the shoring that supports the already stripped slabs, there are shoring joists or profiles interspersed between adjacent decks and in alignments approximately 2m apart. In these systems, before the anticipated recovery of the formwork, struts are transferred from the purlins to these additional elements located between decks. Said elements have projections designed to center the uprights on their lower face and, in some cases, reinforcements to distribute the load of the upright if it coincides with a hollow area of a lightened slab. The costs per linear meter of these additional elements are lower than that of the purlins, however, the anticipated recovery is still not total since there are alignments of these joists in all the propped slabs. Systems with this configuration are described in ES2007490 and ES1015178U. These systems require straps with projections to support the boards on the sides, but it is not necessary for these projections to have a slope (inclination) or other type of special support to facilitate the tilting of the boards.

In an effort to achieve the total anticipated recovery of the formwork, a formwork system described in ES2245265A1 filed by the same applicant is known, which comprises recoverable elements shorter than the boards and arranged between two adjacent boards supported by their ends on the purlins. where the ends of the boards rest. The system requires that the geometry of the ends of the recoverable elements and that of the belts located at their ends be such that they can be tilted. In this case, the total anticipated recovery is achieved by removing the straps located under the center of the decks and disassembling the recoverable elements located between the decks, thus allowing the placement, in the space freed up by them, of props directly in contact with the forged to fell However, it has been found in practice to have some drawbacks.

The main drawback of this system is the lack of flexibility to resolve interferences with vertical structural elements present in a work, such as pillars and diaphragm walls. As in the systems based on small-format boards, it does not offer the possibility of modifying the position of any of the purlin alignments. For the same reason, in the case of using a deck with a length of 2 meters, these systems do not allow the number of deck supports to be easily adapted to 1, 2 or 3 intermediate supports by adding purlin alignments.

DESCRIPTION OF THE INVENTION

The present invention has been developed in order to provide a recoverable setting system that is configured as a novelty within the field of application and solves the aforementioned drawbacks, also providing other additional advantages that will be evident from the description that follows. is attached below.

It is therefore an object of the present invention to provide a recoverable ceiling formwork system that is used for the formation of flat surfaces with concrete material, based on the arrangement of multiple beams (called purlins and purlin carriers) on which they support a plurality of boards, preferably of wood, arranged horizontally, which as a whole can usually adopt a quadrangular or rectangular arrangement that transmits the weight of the concrete elements to vertically arranged struts.

In particular, the invention is characterized by the fact that the boards have a length between 1.9 and 2.5 meters, the formwork system consisting of a plurality of belts arranged in rows that are separated and run preferably parallel to each other. and a plurality of strap holders, both straps and strap holders being intended to be arranged in corresponding horizontal planes, which act as support means for the formwork boards, the strap holders being arranged transversely with respect to the strap arrangement; in which the struts are provided for upper linkage with the purlins; and in which the straps and the strap holders are respectively linked by means of quick coupling systems.

In addition, those purlins arranged in contact with the opposite edges of the boards have a cross section substantially in the form of an inverted "T", having a central part protruding upwards from which two inclined lateral sections extend laterally. each of them in a descending direction from the central part towards the ends, such that the edges of the sides of the board rest on the inclined lateral section; where the strap holders include at least one of their ends a first guide means to support the straps .

Thanks to these characteristics, a recovery system is obtained that requires a smaller number of elements and devices, for example, the use of joists that are usually placed between the setting boards, thus reducing the time of preparation and disassembly for the execution of the setting of a surface, for example, a horizontal surface to form a floor plan of a building. In addition, once the panels or boards have been removed, the set concrete can be supported with the help of props that have been placed as the boards have been removed. Therefore, this system is very suitable for the construction of multi-storey buildings as it reduces execution times between floors.

Another no less important advantage of the described system is the fact that, once the concrete surface has set, it is not necessary to leave straps or similar elements that make it difficult to carry out work in said area, it being only necessary to use a reduced number of props, which also reduces the space for the storage of these elements before and after the execution of the work.

Advantageously, the straps located at the ends of the decks incorporate marking means visible from the lower slab to provide a pattern for the distribution of the props in the re-propping phase.

Preferably, the marking means consist of marks that are equidistantly spaced 20 cm from each other, so that the struts can be arranged at a distance of, for example, 1.80, 2 or 2.20 meters from each other, equidistantly and uniform along the length of the surface to be formworked.

According to the invention, the straps have a cross section substantially in the shape of an inverted "T", having a central part projecting upwards from which they extend laterally two ramps that each extend downwards from the central part towards the ends, the width of the central section being less than a third of the total width of the cross section. Thanks to these characteristics, the disassembly of the boards is facilitated and, consequently, it allows to reduce the time of this operation. This aspect is important since, in the case of building plants with considerable dimensions, the volume of boards can also be high. Preferably, the height of the protruding central part is substantially equal to the thickness of the board.

According to another aspect of the invention, the formwork system's support brackets may include additional guide means intended for the transverse arrangement of the straps.

Preferably, the additional guide means comprise a set of projections that protrude above the profile of the belt holder, the belt holder having a plurality of sets of projections spaced apart from each other.

Another object of the invention is to provide a method for recovering formwork elements from a system such as the one described above. In particular, the recovery method for a ceiling formwork system according to claim 1, characterized in that it consists of the following phases:

a) Disassembly of belt holders and the struts that support them.

b) Dismantling of purlins that are totally under the decks, that is, they are under the underside of the deck;

c) Disassembly of the first alignment of purlins, starting at one end of the formwork area, and recovery of a row of boards;

d) Direct shoring of the floor as close as possible to the next alignment of purlins;

e) Disassembly of the next alignment of belts and recovery of the next row of boards;

f) Direct shoring of the floor as close as possible to the next alignment of purlins; Y

g) Disassembly of the next alignment of belts and recovery of the next row of boards.

It should be noted that this described system dispenses with the usual elements necessary for re-shoring such as shoring joists or recoverable elements shorter than the deck and which are sandwiched between adjacent decks. This feature offers the possibility of laterally moving the straps that support the central area of the table top and/or increasing their number. In this way, the system can be adapted to different loads or deck types and avoid collisions between purlins and vertical structural elements such as pillars or walls.

The recoverable formwork system described thus represents an innovative structure with structural and constitutive characteristics hitherto unknown for its intended purpose, reasons that, together with its practical utility, provide it with sufficient foundation to obtain the privilege of exclusivity that is request.

Other characteristics and advantages of the recoverable formwork system object of the present invention will be evident from the description of a preferred, but not exclusive, embodiment, which is illustrated by way of non-limiting example in the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1.- Is a partial perspective view during assembly of the recoverable ceiling formwork system according to the invention without the boards for the formwork;

Figure 2.- Is a cross-sectional detail view of a strap used in the recoverable formwork system of the invention;

Figure 3.- Is a perspective view of the beams that form part of the formwork system of the invention, where the first quick coupling system is shown in a condition prior to the joining of two linked parts of the beam;

Figure 4.- Is a perspective view of two linked parts of belts with the first coupling system in a functional condition;

Figure 5.- Is a detailed perspective view of a part of the system of the invention where the first guide means present in the belt holders can be seen;

Figure 6.- Is a top perspective view of a phase during formwork using the system of the invention;

Figure 7.- Is a sequential elevation view of the different stages of the recovery procedure for a recoverable ceiling formwork system according to the present invention;

Figures 8a-d.- They are elevation views showing the construction of the roof of various floors of a building;

Figure 9.- Is a sequential view showing how to disassemble a board located at one end of the formwork surface;

Figure 10.- Is a perspective view of a recovery phase of the system according to the present invention;

Figure 11.- Is a perspective view of a second recovery phase of the system according to the present invention; Y

Figure 12.- Is a perspective view of a third recovery phase of the system according to the present invention.

DESCRIPTION OF A PREFERRED EMBODIMENT

In view of the aforementioned figures and, in accordance with the adopted numbering, an example of a preferred embodiment of the invention can be seen in them, which comprises the parts and elements that are indicated and described in detail below.

Furthermore, the terms first, second, third, and the like in the description and claims are used to distinguish between like items and not necessarily to describe a sequential or chronological order. The terms may be interchanged in appropriate circumstances and embodiments of the invention may operate in other sequences than those described or illustrated herein.

Furthermore, the terms top, bottom, top, bottom, and the like in the description and claims are used for purposes of description and not necessarily to describe relative positions.

The embodiment of the present invention provides for a recoverable formwork system that is used for the formation of flat surfaces of concrete elements, based on the arrangement of multiple metallic belts (1) that are all arranged in the same parallel direction, on which a plurality of boards (2) with a rectangular outline, for example, made of wood, that transmit the weight of the elements, are directly supported. concrete elements to struts (4) arranged vertically. These boards can have a length between 1.9 and 2.5 meters.

The belts (1) rest on some belt holders (3) arranged transversely that are supported by struts (4), arranged vertically, with the ability to be adjusted in height by means of a known manual height adjustment system (so it is not going to enter in greater detail in its description), generally indicated with the reference (5), in which the straps are comprised of parts linked together by means of a first quick coupling system (described later), and in which the strap holder ( 3) linked together are linked by a second quick coupling system (also described later), generally indicated with the reference (6).

The straps (1) have a hollow profile with a cross-section with a geometry such that they define a pair of lateral flanges (11) intended to support the boards (2) used to support the weight of the concrete. When extracting the belt holders (3) to recover the belts (1) and the boards, parts of the belt (1) are likely to tilt at the point where the first quick coupling system is for its removal.

It should be noted that the lateral flanges (11) are inclined downwards with respect to the horizontal plane, as can be seen more clearly in figure 2, so that they facilitate the disassembly of the boards (2) during the recovery procedure.

As can be seen in Figures 1 and 6, the belt holders (3) have, at one of their ends, first guiding means for positioning the belts (1), which comprise U-shaped plates (7) between them. which the belt (1) is likely to pass.

Now making particular reference to the quick coupling system linked to the belt (1), it comprises a trigger (8) present in a part of the belt that is rotatably articulated therein, the trigger being attachable to a pin (9) present in the belt. adjoining strap part by a downward movement of the strap part provided with the trigger. Figure 3 shows in greater detail the components that are part of the first quick coupling system, while figure 4 can be seen as two parts linked from a belt are coupled to each other through the first coupling system.

With reference to the second quick-coupling system intended to link strap-holders (3), it comprises a trigger present on a strap-holder that is rotatably articulated thereon, the trigger being engageable on a pin present on the adjacent strap-holder by means of a downward movement of the strap-holder provided with the trigger.

Advantageously, the straps (1) include on their lower face a plurality of pivots (10) that extend downwards, which can be equidistant from each other or in a specific distribution, being provided for the coupling of the struts (4).

The belt carriers (3) include additional guide means provided for the transverse arrangement of the belt carriers (3). These additional guide means comprise a set of projections (12) that protrude above the profile of the belt holder (3), the belt holders having a plurality of sets of projections (12) spaced apart from each other.

To recover the different elements used for an adequate setting of a concrete surface of the type shown in different figures, it is carried out by means of a procedure that has the following stages (see figures 7 to 11):

a) Disassembly of the belt holders (3) and those vertical struts (4) that support them;

b) Disassembly of a first alignment of purlins, starting at one end of the formwork area, and extraction of a row of boards (2);

c) Shoring directly from the slab as close as possible to the next alignment of purlins by arranging struts that have been previously extracted in step a) above;

d) Disassembly of the next alignment of belts and recovery of the next row of boards (2);

e) Direct shoring of the floor as close as possible to the next alignment of purlins (1); Y

f) Disassembly of the next alignment of belts and recovery of the next row of boards that is parallel to the previous row of boards (2).

Figures 8a to 8d show the different construction stages of a multi-storey building at different heights, where the advantages of the recovery procedure for the elements used in the formwork system described above can be seen.

The details, shapes, dimensions and other accessory elements used in the manufacture of the recoverable setting system of the invention may be conveniently replaced by others that do not deviate from the scope defined by the claims included below.

Numerical references:

1. strap

2. board

3. strap holder

4. strut

5. height adjustment system

6. second quick coupling system

7. platen

8. trigger

9. pin

10. pivot

11. side flange

12. highlights

100. concrete surface

Claims (11)

1. Recoverable ceiling formwork system used for the formation of flat surfaces of concrete elements, based on the arrangement of multiple beams on which a plurality of boards (2) are supported, adopting a horizontal arrangement, preferably of wood, which transmit the weight of the concrete elements to vertically arranged props, characterized by the fact that the boards (2) have a length between 1.9 and 2.5 meters, the formwork system consisting of a plurality of straps (1) arranged in alignments that are separated from each other and a plurality of strap holders (3), both straps and strap holders being intended to be arranged in a corresponding horizontal plane, which act as a support means for the formwork boards, the straps being belt holders (3) arranged transversely with respect to the arrangement of belts (1); in which the struts (4) are intended to be linked at the top with the straps (1) and strap holders (3); and in which the straps and the strap holders are respectively linked by means of quick coupling systems; in which the straps (1) arranged in contact with the opposite edges of the boards have a cross section substantially in the form of an inverted "T", having a central part protruding upwards from which two inclined lateral sections extend laterally. each of them extend downwards from the central part towards the ends, such that the edges of the sides of the deck rest on the inclined lateral section; and where the belt holders include at least one of the ends some first guide means to support the belts (1). 2. Recoverable ceiling formwork system according to claim 1, characterized in that the straps located at the ends of a group of boards (2) incorporate marking means visible from the lower slab to offer a pattern of distribution of the struts (4). 3. Recoverable ceiling formwork system according to claim 2, characterized in that the marking means consist of marks that are equidistantly spaced 20 cm apart. 4. Recoverable ceiling formwork system according to claim 1, characterized in that the purlins (1) have a cross section substantially in the shape of an inverted "T", having a central part protruding upwards from which two laterally extending ramps that each extend downwards from the central part towards the ends. 5. Recoverable ceiling formwork system according to claim 4, characterized in that the height of the central part of the protruding cross-section is substantially equal to the thickness of the board (2). 6. Recoverable ceiling formwork system according to claim 4, characterized in that the width of the central section is equal to or less than one third of the total width of the cross section. 7. Recoverable ceiling formwork system according to claim 1, characterized in that the quick coupling system for the straps comprises a trigger present at one end of the strap (1) which is rotatably articulated on it, being the trigger attachable to a pin present at one end of the adjoining strap. 8. Recoverable ceiling formwork system according to claim 1, characterized in that the quick coupling system for the strap holders (3) comprises a trigger present at a point along the strap holder, which is rotatably articulated in this one, being the trigger attachable in a pin present in the adjoining belt holder. 9. Recoverable ceiling formwork system according to claim 1, characterized in that the strap holders (3) include additional guide means provided for the transverse arrangement of the strap holders (3). 10. Recoverable ceiling formwork system according to claim 9, characterized in that the additional guide means comprise a set of projections that protrude above the profile of the belt carrier, the belt carriers having a plurality of sets of projections spaced apart from each other. Yes. 11. Recovery procedure for a recoverable ceiling formwork system according to any of claims 1 to 10, characterized in that it consists of the following steps: a) Disassembly of the belt holders (3) and the struts that support them; b) Dismantling of straps (1) that are located below the lower face of the boards; c) Disassembly of a first alignment of purlins, starting at one end of the formwork area, and extraction of a row of boards; d) Direct shoring of the floor as close as possible to the next alignment of purlins; e) Disassembly of the next alignment of belts and recovery of the next row of boards (2); f) Direct shoring of the floor as close as possible to the next alignment of purlins (1); Y g) Disassembly of the next alignment of belts and recovery of the next row of boards (2) parallel to the previous row of boards (2).