CONCRETE TOWER AND CLIMBING OR SELF-CLIMBING FORMWORK DEVICE FOR ITS BUILDING ONSITE

Abstract

The tower, applicable in the installation of wind turbines, comprises: a lower end (11) having a general polygonal configuration formed by flat sides (12) and cylindrical portions (13) arranged between consecutive flat sides (12); the flat sides (12) having a decreasing width in the upward direction throughout the tower (1), and the cylindrical portions (13) having an invariable shape throughout the tower (1); the tower (1) having, at its top end (11), a circular outline made by the cylindrical portions (13), which maintain an invariable shape throughout the tower (1). The invention includes a climbing formwork device for building the tower.

Claims

1. A concrete tower, applicable in the installation of wind turbines, comprising a hollow sectional body of varying cross-section in the vertical direction, characterized in that it comprises: a lower end (11) having a general polygonal configuration formed by flat sides (12) and cylindrical portions (13) arranged between the consecutive flat sides (12); the flat sides (12) having a decreasing width in the upward direction throughout the tower (1), and the cylindrical portions (13) having an invariable shape throughout the tower (1); the tower (1) having, at its top end (11), a circular outline, consisting of the cylindrical portions (13) maintaining an invariable shape throughout the tower (1); and a climbing or self-climbing formwork device for building onsite the tower characterized in that it comprises: corner pieces (2a, 2b) of formwork for defining the cylindrical portions (13) of the tower; which pieces have an upper end (21) and a lower end (22) defining two parallel planes; a curved area (23) oriented longitudinally along said corner pieces (2a, 2b); said curved area (23) having a constant curvature radius and a straight generatrix with a predetermined slope with respect to the parallel planes defined by the upper and lower ends (21, 22) of said corner pieces; intermediate rectangular pieces (3), which are arranged laterally attached between the corner pieces (2a, 2b) and with the same slope as the generatrix of the corner pieces; said rectangular pieces (3) defining, in successive sections of formwork, flat surfaces corresponding to the flat sides (12) of the tower. having the corner pieces (2a), on opposite sides of the curved area (23), a respective flat extension (24) of triangular-rectangular configuration, each of said flat extensions (24) having a base and a height of dimensions matching respectively with the half of the base and with the height of the rectangular pieces (3).

2. The concrete tower according to claim 1, characterized in that the flat sides (12) have a decreasing width in the upward direction from a maximum width corresponding to the lower end of the tower, and a zero width at the top end of the tower.

3. (canceled)

4. (canceled)

5. The formwork device according to claim 1, characterized in that it comprises flat pieces (4) of triangular-rectangular configuration, which have a base and a height of dimensions matching respectively with the half of the base and with the height of the rectangular pieces (3), and which are arranged in the formwork of each tower section (1) one to each side of the curved corner pieces (2b).

6. The formwork device according to claim 1; characterized in that the curved area (23) of the corner pieces (2a, 2b) of the formwork have a constant width in the direction of the generatrix.

7. The formwork device, according to claim 1, characterized in that the corner pieces (2a, 2b) of the formwork are provided with holes (25) for anchorage to the lifts or for positioning of self-climbing guides or rails.

Description

DESCRIPTION OF THE FIGURES

[0024] In order to complement the description that is being carried out and with the purpose of facilitating the understanding of the features of the invention, the present description is accompanied by a set of drawings wherein, by way of a non-limiting example, the following has been represented:

[0025] FIG. 1 shows an elevational view of an exemplary embodiment of the four-sided tower according to the invention.

[0026] FIG. 2 shows a top plan view of the four-sided tower of the above figure.

[0027] FIG. 3 shows a perspective view of the different constituent parts of an exemplary embodiment of a formwork device for building the four-sided tower of the above figures.

[0028] FIGS. 4a to 4g show schematically successive building stages of the last three sections of the concrete tower of FIGS. 1a and 1b with the formwork device shown in FIG. 3.

[0029] FIG. 5 shows a perspective exploded view of the different constituent parts of an embodiment variant of the formwork device shown in FIG. 3 for a four-sided tower.

[0030] FIGS. 6 and 7 show both elevational and top plan views of an exemplary embodiment of a three-sided tower according to the invention.

[0031] FIG. 8 shows an embodiment variant of the formwork shown in FIG. 3, suitable for the construction of three-sided towers, representing the last three sections of formwork for building a triangular tower.

PREFERRED EMBODIMENT OF THE INVENTION

[0032] As can be seen in FIG. 1, the concrete tower referenced as (1) as a whole comprises a hollow concrete body, of varying cross-section in vertical direction, said tower having a lower end (11) with a polygonal configuration formed by flat sides (12) and cylindrical portions (13) arranged between consecutive flat sides (12).

[0033] The flat sides (12) of the tower have a decreasing width in the upward direction throughout the tower until reaching a top end (14), where the flat sides (12) have zero width; and the cylindrical portions (13), of invariable shape and constant curvature radius throughout the tower, converge with each other providing said top end (14) with a circular outline.

[0034] In the embodiment shown in FIGS. 3 and 4, a formwork device comprising formwork corner pieces (2a) for defining the cylindrical portions (13) of the tower (1) and intermediate rectangular pieces (3) of a height equal to that of the corner pieces (2a) can be seen.

[0035] Said corner pieces (2a) have an upper end (21) and a lower end (22) defining two parallel and horizontal planes in the use position of the formwork; said pieces (2a) further having a curved area (23) longitudinally oriented and two flat extensions (24) of triangular-rectangular configuration arranged on opposite sides of the curved area (23).

[0036] Said curved area (23) has a constant curvature radius and a straight generatrix with a predetermined slope for the parallel planes defined by the upper and lower ends (21, 22) of said corner pieces. The slope of said generatrix is that which defines the slope of the cylindrical portions (13) in the tower (1).

[0037] The flat extensions (24) defined on opposite sides of the corner pieces (2a) have a base and height of dimensions matching with the half of the base and height of the rectangular pieces (3), arranged in the use position of the formwork coplanar with said rectangular pieces (3) to form the flat sides (12) of the tower (1).

[0038] FIGS. 4a to 4g show successive building steps of the last three sections of the concrete tower (1) represented in FIGS. 1 and 2, using the climbing technique and the formwork pieces shown in FIG. 3; considering that in a tower of more than 120 m. high the number of sections would be greater than 24 for a 5-metre formwork.

[0039] Specifically, in FIG. 4a, a first section (E n-2) of formwork is formed arranging four corner pieces (2a) with their lower ends (22) coplanar and four pairs of intermediate rectangular pieces (3) arranged between and laterally attached to the corner pieces (2a).

[0040] Subsequently, as shown in FIG. 4b, the concrete is poured into the interior of the first section of formwork (E n-2) and it is left to set to obtain a first section of the tower (T n-2).

[0041] Subsequently, as shown in FIGS. 4c and 4d, a second section of formwork (E n-1) is formed by removing on each side thereof one of the intermediate pieces (3).

[0042] The flat extensions (24) of triangular-rectangular configuration defined on the opposite sides of the corner pieces (2a) have at their base a width equal to half of the width of the rectangular pieces (3), which ensures that in this second section of formwork (E n-1) the corner pieces (2a) and the rectangular pieces (3) are perfectly attached laterally, this second section of formwork (E n-1) defining interiorly a constituent surface of an extension of the surface of the first tower section (T n-2) previously built.

[0043] Afterwards, as shown in FIG. 4d, the concrete pouring is performed in the interior of the second section of formwork (E n-1) to build a second tower section (T n-1).

[0044] In order to perform the climbing of the formwork, it is envisaged that the pieces thereof can be supported by anchorages arranged in the previous lift. Thus, either by the help of a crane (climbing formwork) or with automatic climbing elements (self-climbing formwork), the formwork is positioned in the successive lifts.

[0045] The constant curvature of the corner pieces (2a) allows them to be moved in the direction of the generatrix of its curved area (23) to be arranged in successive sections of the formwork, ensuring the definition of the cylindrical portions (13) in the tower.

[0046] As can be seen in FIGS. 4e and 4f, once the sections (T n-2, and T n-1) of the tower are built, the rectangular pieces (3) are removed from the second section of formwork (E n-1) and the pieces (2a) are conveniently positioned to form a third section of formwork (E n) in which said pieces (2a) are attached directly to each other, this third section of formwork (E n) having a round upper mouth.

[0047] Through the pouring of concrete into its interior, as shown in FIG. 4f, and the setting thereof, a third and final section (T n) of the tower (1) represented in FIG. 4g is formed.

[0048] FIG. 5 shows an embodiment variant of the formwork of FIG. 3, which has an operation similar to that described in FIG. 4 and the only difference is that the corner pieces (2b) do not have flat extensions (24) on their sides, this formwork comprising instead flat pieces (4) of triangular-rectangular configuration and dimensions analogous to the said flat extensions (24) and which fulfil the same function as those.

[0049] With this formwork design, for application in wind turbines, after defining the section corresponding to the last section of formwork (E n), modifying the number of rectangular pieces (3) used in the formwork section corresponding to the base or lower end of the tower, a tower with different sizes of base and height can be built without having to modify the corner pieces (2b).

[0050] FIGS. 6 and 7 show an embodiment variant of the tower, with features similar to the tower described above, but with three flat sides (12) and three cylindrical portions (13) instead of four; in this case being built with a formwork shown in FIG. 8, wherein the corner pieces (2a) have a curved area (23) corresponding to a cylindrical sector of an amplitude equal to one third of the outline of a cylinder.

[0051] As can be seen from the exploded views of the two formwork embodiments, shown in FIGS. 3 and 5, the corner pieces (2a, 2b) of the formwork are provided with holes (25) for anchorage to the lifts or for positioning of self-climbing guides or rails.

[0052] Once the nature of the invention as well as an example of preferred embodiment have been sufficiently described, it is stated for all pertinent purposes that the materials, form, size and arrangement of the elements described are susceptible to changes, provided these do not involve an alteration of the essential features of the invention that are claimed subsequently.