Apparatus for forming concrete tubular elements, in particular tunnel or conduit sections

Abstract

An apparatus (1) for forming tubular elements made of concrete comprises: - a rotating cylinder (2) driven by a motor (3), extending along a longitudinal axis (L) between an entrance end (4) and an exit end (5), and comprising a guide (6) helically wound around at least a portion of the cylinder (2) from the entrance end (4); - a fixed retaining wall (7) extending circumferentially around the rotating cylinder (2) at the entrance end (4) thereof; - an armour feeder (9) configured for feeding the rotating cylinder (2) with a continuous armour stripe (10) on the guide (6) at the cylinder entrance end (4), such that, as a consequence of the cylinder (2) rotation, the armour stripe (10) is progressively wound around the cylinder (2) along the guide (6); - a concrete provider (14) configured for feeding concrete on the fed armour stripe (10), such that, upon rotation of the cylinder (2), the armour stripe (10) progressively wound along the guide (6) is progressively covered by a continuous concrete layer.

Description

[0001] “Apparatus for forming concrete tubular elements, in particular tunnel or conduit sections”

[0002] DESCRIPTION

[0003] TECHNICAL FIELD OF THE INVENTION

[0004] The present invention relates to an apparatus for forming tubular elements made of concrete, such as concrete tubular sections of a tunnel, in particular an underwater tunnel, or of a tubular conduit in general.

[0005] PRIOR ART

[0006] With reference to the field of tunnels, in particular underwater or submarine tunnels, they are made of inter-connected tubular sections made of concrete, which are manufactured in the factory and then delivered to the tunnel site. These tunnel sections are very big (with diameters in general up to 20 meters) and, due to their dimensions, their transportation is very difficult, expensive, time-consuming and has an environmental impact.

[0007] SUMMARY OF THE INVENTION

[0008] Therefore, it is an object of the present invention to provide an apparatus for forming concrete tubular elements, such as tunnel or conduit tubular sections, possibly directly on site, thereby substantially avoiding the transportation of the same and reducing the costs and the overall time for the tunnel / conduit construction, and the environmental impact as well.

[0009] This and other objects are achieved by an apparatus for forming concrete tubular elements according to claim 1.

[0010] Dependent claims define possible advantageous embodiments of the invention.

[0011] BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to better understand the invention and appreciate its advantages, some non- limiting exemplary embodiments will be described below, referring to the attached figures, wherein:

[0013] Figure 1 is a schematic view of an apparatus for forming concrete tubular elements according to an embodiment of the invention;

[0014] Figure 2 is schematic side view of a rotating cylinder of the apparatus of Figure 1; Figure 3 is a schematic view of an armour stripe used in the apparatus according to an embodiment of the invention.

[0015] DETAILED DESCRIPTION OF THE INVENTION

[0016] With reference to the attached Figures 1-2, a scheme of an apparatus for forming concrete tubular elements is shown as a whole under reference 1. As per the introductory part of the present description, the above-mentioned tubular elements can comprise for example tubular sections of a tunnel, in particular an underwater tunnel, or of a tubular conduit.

[0017] The apparatus 1 comprises a rotating cylinder 2 driven by a motor 3, for example an electric actuator. A transmission can be operatively interposed between the cylinder 2 and the motor 3. The cylinder 2 extend along a longitudinal axis L between an entrance end 4 and an exit end 5. For example, the cylinder 2 can be made of steel. Its diameter depends on the desired diameter of the tubular element to be formed.

[0018] The cylinder 2 can be positioned such that the longitudinal axis L is horizontal, or alternatively, is inclined so to form an angle a with a horizontal support base 100, preferably with the entrance end 4 at a higher height than the exit end 5.

[0019] According to an embodiment, the apparatus 1 comprises means 19 for regulating the inclination of the cylinder 3 longitudinal axis L, i.e. for modifying the angle a. For example, such means can comprise hydraulic or pneumatic or electric actuators.

[0020] The cylinder 3 comprises a guide 6 helically wound around the cylinder external surface, developing along the longitudinal axis L from the entrance end 4 preferably for just a portion of the cylinder, i.e. not for the whole length of the cylinder. For example, the guide 6 can comprise a helical groove formed on the cylinder 2 external surface. The function of the guide 6 will be described more in detail below. Preferably, the guide 6 extends along the longitudinal axis L for at least three turns.

[0021] The apparatus 1 further comprises a fixed retaining wall 7 extending circumferentially around the cylinder 2, at a radial distance therefrom, at the entrance end 4 thereof. Preferably, the fixed retaining wall 7 extends circumferentially around the cylinder for less than 360°, such that an aperture 8 where the cylinder 2 is accessible near the entrance end 4 is formed. Preferably, the aperture 8 is positioned at the highest radial position of the cylinder 2. In an embodiment, the fixed retaining wall 7 extends circumferentially from the cylinder radial highest position for at least 180°, preferably up to 270°.

[0022] In an embodiment, the fixed retaining wall 7 width is the same or substantially the same as the guide 6 extension along the longitudinal axis L, i.e. it covers the cylinder 2 external surface from the entrance end 4 for just a longitudinal portion where the guide 6 is present.

[0023] The apparatus 1 further comprises an armour feeder 9 configured for feed the cylinder 2 with a continuous armour stripe 10 on the guide 6 at the cylinder entrance end 4, for example at the aperture 8.

[0024] Advantageously, the helically wound guide 6 pitch is the same or substantially the same as the armour stripe 10 width. Still more advantageously, the guide 6 (and / or the armour stripe 10) is configured such that the armour stripe 8, as a consequence of the feeding on the cylinder 2 which rotates, is progressively locked on the guide itself, radially raised with respect to the cylinder external surface (e.g. from the bottom of the helical groove), preferably in a radially intermediate position between the cylinder 2 external surface and the retaining wall 7, and follows the helical path of the guide 6 itself. According to an embodiment, the armour feeder 9 comprises a track 11 moving the armour stripe 10 to the cylinder 2 and an armour source 12 from which the armour stripe 10 is taken and put on the track 11. The armour source 12 can be a container where the pre-manufactured armour stripe is contained or, alternatively, can comprise a device for manufacturing the armour stripe 10 on site, such as a forging and welding machine. The track 11 is preferably positioned on a tower 17 such that it can reach the aperture 8.

[0025] The armour stripe 10 (Figure 3) can comprise a reinforced mesh made for example of a steel. Advantageously, the armour stripe 10 comprise, on its longitudinal lateral sides, anchoring means 13 configured such that, when two portions of the armour stripe 10 are positioned side-by-side, they connect each other through the anchoring means 13. For example, the anchoring means 13 are zip-shaped. In this manner, when successive portions of the armour stripe fed on the cylinder are side by side on the guide 6 as a consequence of the cylinder rotation, they are interlocked by the anchoring means 13. The anchoring means 13 can also form means for locking the armour stripe 10 to the guide 6.

[0026] Referring back to Figures 1 and 2, the apparatus 1 further comprises a concrete provider 14 configured for feeding concrete on the guide 6 at the cylinder entrance end 4, such that, upon rotation of the cylinder 2, the armour stripe 10 fed to the guide 6 is progressively covered by concrete and the armour stripe 10 portions inter-locked side by side through the anchoring means 13 are covered by a continuous concrete layer.

[0027] More in detail, in an embodiment the concrete provider 14 comprises a container 15, for example with a mixer, and a first concrete feeder 16 and a second concrete feeder 17. The first concrete feeder 16 feeds concrete on the track 11 such that the armour stripe 10 is firstly covered by concrete before reaching the cylinder 2. The second concrete feeder 17 feeds concrete on the guide 6 near the cylinder entrance end 4, for example at the aperture 8, such that the already covered armour stripe 11 is further covered by concrete and sandwiched in the same. In this manner, side-by-side portions of the armour stripe 10 are progressively continuously sandwiched in a single continuous layer of concrete. During the rotation of the cylinder 2, the concrete layer where the armour stripe 10 is sandwiched is pressed and shaped by the retaining wall 7, which, to this purpose, can optionally comprise suitable rollers (not shown) on the side facing the cylinder 2.

[0028] As an effect of the rotation of the cylinder 2 and of the presence of the helically wound guide 6, a concrete tubular element reinforced with the helically wound armour stripe 10 (which is continuous, too) is formed and moved along the longitudinal axis L towards the cylinder exit end 5. Once the tubular element has reached a desired length, the feeding of both the armour stripe 10 and of concrete are stopped and the so formed tubular element can be pushed outside the rotating cylinder.

[0029] Advantageously, concrete is formulated such that during the formation of the tubular element the concrete is not fully hardened but becomes hardened at the end of the abovedescribed process. In an embodiment, the concrete is still not fully hardened when the formed concrete tubular element is pushed outside the rotating cylinder 2.

[0030] It is further observed that when the partially formed tubular element goes beyond the end of the helically wound guide 6, it can be further worked or covered, for example with a protective layer, for example made of aluminium or other protective materials.

[0031] The so formed tubular elements can be manufactured directly on site and connected in longitudinal direction to form for example a tunnel or a conduit, without the need of any long transportation from a factory.

[0032] To the described embodiments of the apparatus for forming concrete tubular elements, the skilled person, in order to meet specific contingent needs, may make numerous additions, modifications, or substitutions of elements with functionally equivalent ones, without, however, departing from the scope of the attached claims.

Claims

CLAIMS1. An apparatus (1) for forming tubular elements made of concrete, comprising:- a rotating cylinder (2) driven by a motor (3), extending along a longitudinal axis (L) between an entrance end (4) and an exit end (5), and comprising a guide (6) helically wound around at least a portion of the cylinder (2) from the entrance end (4);- a fixed retaining wall (7) extending circumferentially around the rotating cylinder (2) at the entrance end (4) thereof;- an armour feeder (9) configured for feeding the rotating cylinder (2) with a continuous armour stripe (10) on the guide (6) at the cylinder entrance end (4), such that, as a consequence of the cylinder (2) rotation, the armour stripe (10) is progressively wound around the cylinder (2) along the guide (6);- a concrete provider (14) configured for feeding concrete on the fed armour stripe (10), such that, upon rotation of the cylinder (2), the armour stripe (10) progressively wound along the guide (6) is progressively covered by a continuous concrete layer.

2. The apparatus (1) of claim 1, wherein the guide (6) extends along the cylinder (6) longitudinal axis (L) for at least three turns.

3. The apparatus (1) of claim 1 or 2, wherein the guide (6) is configured such that, for each turn around the cylinder (2), the portions of the armour stripe (10) wound along the guide (6) are positioned side-by-side with the portions of the armour stripe (10) of the preceding turn.

4. The apparatus (1) of any of the preceding claims, wherein the helically wound guide (6) pitch is the same or substantially the same as the armour stripe (10) width.

5. The apparatus (1) of any of the preceding claims, wherein the guide (6) and / or the armour stripe (10) are configured such that the armour stripe (10) on the guide (6) is positioned radially raised with respect to the cylinder (2) external surface at a radiallyintermediate position between the cylinder (2) external surface and the fixed retaining wall 0-6. The apparatus (1) of any of the preceding claims, comprising means for locking the armour stripe (10) to the guide (6) .

7. The apparatus (1) of any of the preceding claims, wherein the armour stripe (10) comprises a mesh having on its longitudinal lateral sides anchoring means (13) configured such that, when two portions of the armour stripe are positioned side-by-side, they connect each other through the anchoring means (13).

8. The apparatus (1) of claims 6 and 7, wherein said anchoring means (13) form said means for locking the armour stripe (10) to the guide (6).

9. The apparatus (1) of claim 7 or 8, wherein the anchoring means (13) are zip-shaped.

10. The apparatus (1) of any of the preceding claims, wherein the fixed retaining wall (7) extends circumferentially around the rotating cylinder (2) for less than 360°, such that an aperture (8) where the rotating cylinder (2) is accessible near the entrance end (4) is formed.

11. The apparatus (1) of any of the preceding claims, wherein the fixed retaining wall (7) width is the same or substantially the same as the guide (6) extension along the cylinder (2) longitudinal axis (L).

12. The apparatus (1) of any of the preceding claims, wherein the armour feeder comprises an armour stripe source (12) and a track (11) for moving the armour stripe (10) from the armour stripe (12) source towards the cylinder entrance end (4).

13. The apparatus (1) of the preceding claim, wherein the armour stripe source (12) comprises a container where the pre -manufactured armour stripe (10) is stored or a machine for producing the armour stripe (12).

14. The apparatus (1) of claim 12 or 13, wherein the concrete provider (14) comprises afirst concrete feeder (16) for feeding concrete on the track (11) such that the armour stripe (11) is partially covered by concrete on the track before reaching the cylinder (2) entrance end (4).

15. The apparatus (1) of any of the preceding claims, wherein the concrete provider (14) comprises a second concrete feeder (17) for feeding concrete on the guide (6) near the cylinder entrance end (4), such that the armour stripe (10) is progressively and continuously covered by concrete along the guide (6).

16. The apparatus (1) of any of the preceding claims, wherein the longitudinal axis (L) of the rotating cylinder (2) is inclined such that the entrance end (4) is at a higher height than the exit end (5) .

17. The apparatus (1) of any of the preceding claims, comprising means for regulating the inclination of the longitudinal axis (L) of the rotating cylinder (2) .

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