WIND TOWERS CONSTRUCTION SYSTEM

Abstract

The invention relates to a system having multiple improvements compared to conventional systems for building wind towers made of section of reinforced concrete, in order to significantly reduce building costs. Such improvements include: obtaining a profile extruding from truncated cone sections that conform as much as possible to the ideal curved profile of the tower; using pre-stretched cables, which are factory-tensioned before installing the rebar, and tendons that pass through the arch stones, making it possible to link various arch stones with one another; and reducing the thickness of the arch stones; and arranging the rebar in only one layer, as well as other improvements described through the present invention.

Claims

1. Wind towers construction system, of the type formed from a series of vertical sections of reinforced concrete, obtained by means of the joining of two or more arch stones, wherein the different sections that participate in the tower have a truncated cone configuration, of different inclination for each section, so that an uneven profile is obtained as close as possible to the theoretical and optimum curved profile, provided for the tower, characterized in that for the fixing of the tower to the base shoe, it has been provided that from the base shoe (9) emerge respective tendons (5), which by means of connections (10) are fixed to the tendons (5) of the arch stones, said tendons (5) of height slightly higher than the high of the arch stones which are going to form the first section of tower, which incorporate longitudinal orifices (11) wherethrough these tendons are made to pass, being tensioned above the horizontal joint between the first and the second section of the tower.

2. Wind towers construction system, according to claim 1, wherein the arch stones (4) which participate in the sections into which the tower is divided are vertically interlinked from cable tendons (5), which run vertically through the interior of the arch stones and are made to pass through respective orifices (6) made in respective prominent elements (7) of the edges which are defined in the horizontal joint of the arch stones (4), so that a same tendon (5) of an arch stone is linked by one of its ends with the arch stone immediately above it, and by the other end with the arch stone immediately below it.

3. Wind towers construction system, according to claim 2, wherein the tendons (5) are clad with a rubber coating.

4. Wind towers construction system, according to claim 1, wherein the thickness of the arch stones (4) is in the order of 12 centimetres, having provided that the rebar (12) is disposed in a single layer.

5. Wind towers construction system, according to claims 2, wherein the arch stones (4) include pre-tensioned frames as part of the active frame, so that in addition to the tendons (5) which run through the interior of the arch stones, the adherent cords or tendons (5) are disposed, which are factory-tensioned before placing the general rebar of the arch stone in the mould, before the concreting thereof.

6. Wind towers construction system, according to claim 4, wherein the areas of the base and the head of the arch stone corresponding to the prominent sectors (7) have an extra thickness in the order of 30-40 centimetres, whereon the lifting and handling fastenings are established.

7. Wind towers construction system, according to claim 4, wherein the prominent sectors (7) where the active fastenings (8) of the tendons (5) are established, are disposed on a smooth surface of revolution which extends circumferentially.

8. Wind towers construction system, according to claim 4, wherein the prominent elements (7) wherein the active fastenings (8) of the tendons (5) are established, are disposed in a series of boxes (13) or specific recesses, distributed radially.

9. Wind towers construction system according to claim 4, wherein the arch stones (4) include pre-tensioned frames as part of the active frame, so that in addition to the tendons (5) which run through the interior of the arch stones, the adherent cords or tendons (5) are disposed, which are factory tensioned before placing the general rebar of the arch stone in the mould, before the concreting thereof.

Description

DESCRIPTION OF THE DRAWINGS

[0026] To complement the description being made and in order to aid towards a better understanding of the characteristics of the invention, in accordance with a preferred example of practical embodiment thereof, a set of drawings is attached as an integral part of said description wherein, with illustrative and non-limiting character, the following has been represented.

[0027] FIG. 1.Shows a profile view of a wind tower, the scale of which has been vertically deformed to be able to see with greater ease the theoretical profile of the tower and the real profile thereof.

[0028] FIG. 2.Shows a diagrammatic perspective view of a section formed by several arch stones.

[0029] FIG. 3.Shows a detail in vertical section of the joining profile between arch stones, corresponding to a first variant of embodiment wherein boxes are defined for housing the active and passive ends for tightening the tendons.

[0030] FIG. 4.Shows a view similar to that of FIG. 3, but corresponding to a variant of embodiment wherein the boxes are eliminated to house the active and passive ends for tensioning the tendons.

[0031] FIGS. 5 and 6.Show different details in sequential sections of the fixing means of the lower arch stone to the base shoe.

[0032] FIG. 7.Shows, finally, a sectional detail in accordance with a horizontal cut plane of an arch stone, in order to be able to view the frame which participates therein.

PREFERRED EMBODIMENT OF THE INVENTION

[0033] As can be seen in the aforementioned figures, and in particular in FIGS. 1 and 2, the tower (1) of the invention is formed from a series of vertical sections (2) obtained in turn from two or more arch stones (4), so that, against the ideal theoretical curved profile (3), which due to calculations the tower should have, it has been provided that said profile is obtained from straight segments (13), for which reason the vertical sections which participate in the tower have a truncated cone configuration with straight directrix.

[0034] Consequently, the different sections of the tower will have a straight profile, although their inclination shall be different, unlike what happens with conventional straight profile towers.

[0035] As can be observed in FIGS. 3 and 4, and in accordance with another of the characteristics of the invention, it has been provided that in replacement of the classic fixing means in the horizontal joints between arch stones, the arch stones are vertically interlinked with cable tendons (5), which run vertically through the interior of the arch stones emerging at both ends in perfectly vertical position to allow in the assembly process, the introduction through respective orifices (6) made in respective prominent elements (7) of the edges defined in the horizontal joint of the arch stones (4), so that a same tendon (5) of an arch stone is linked by one of its ends with the arch stone immediately above it, and at the other end with the arch stone immediately below it, by means of the corresponding active (8) and passive (8) fastenings.

[0036] The tendons (5), as previously mentioned are clad with a coating and are tensioned in the wind farm after assembly of the tower sections.

[0037] In accordance now with FIGS. 5 and 6, when fixing the tower to the foundations or base shoe (9) it has been provided that respective vertical tendons emerge therefrom, which by means of connections (10) are fixed to tendons (5) of the arch stones which are going to form the first tower section, which incorporate longitudinal orifices (11) wherethrough these tendons are passed, tensioning them above the horizontal joint between the first and the second section, so that the tendons have a sufficiently large length so that the elongation, if tensioned, is sufficiently large so that the losses occurred in the fastening of the chocks when the jacks are removed, do not excessively decrease the elongation of the tensioning and, therefore, the tension of the tendon.

[0038] As regards the thickness of the arch stones (4) it has been provided that it is reduced, thus reducing the weight, which facilitates the assembly of the sections in the wind farm, especially in towers of great height.

[0039] Therefore, and as observed in FIG. 7, it has been provided that the rebar (12) is disposed in a single layer, instead of in the two conventional layers.

[0040] More specifically, the use of pre-tensioned frames has been provided as part of the active frame, so that in addition to the tendons (5) that run through the interior of the arch stones, adherent cords or tendons (5) are disposed that, are factory-tensioned before placing the general rebar of the arch stone in the mould, before the concreting thereof.

[0041] These cords or tendons (5) as previously commented, collaborate with the general frame of the arch stone to withstand the operating stresses in service of the tower, additionally having two functions; on the one hand, withstanding the stresses of the arch stone in the handling operations thereof, demoulding, stockpiling, transport and pre-assembly, and, in parallel, serving as support and fixing of the rebar grilles on most of the arch stone surface, eliminating part of the separation elements of the rebar and maintaining the foreseen concrete coatings.

[0042] The aforementioned reduced thickness makes it necessary to displace the lifting and handling fastenings to the areas of the base and the head of the arch stone (4), corresponding to the prominent sectors of greater thickness (7). This extra thickness makes it possible to situate with clearance the fastenings, even decreasing their number from 4 to 2 units.

[0043] Finally, and again in accordance with FIGS. 3 and 4, the prominent elements (7) wherein the active (8) and passive (8) fastenings of the tendons (5) are established, and specifically the surface where said fastenings are fixed, may constitute a surface of smooth revolution, which extends circumferentially, as shown in FIG. 4, or boxes or specific recesses can be established, which are radially distributed, as in the example of FIG. 3.