EP0009056A1

EP0009056A1 - Method of manufacturing concrete tubular building elements

Info

Publication number: EP0009056A1
Application number: EP78200178A
Authority: EP
Inventors: Cornelis Anthonius Zandbergen; Johannes Teunis De Heus
Original assignee: WACO BETON BV; Ballast Nedam Groep NV
Current assignee: Ballast Nedam NV; WACO BETON BV
Priority date: 1978-09-06
Filing date: 1978-09-06
Publication date: 1980-04-02
Also published as: EP0009056B1; JPS5818212B2; DE2861408D1; JPS5544895A; CA1115072A

Abstract

In order to dismantle during the manufacture of a concrete building element (3) the casting in a simple and reliable manner without damage, so that the casting mould (5) can be rapidly used for a next manufacturing process, the upper gauge (9) of the casting mould is retained against the still incompletely cured concrete mortar (10) of the casting, whilst the casting is removed from a core (8) and a jacket (7) of the casting mould (5).

Description

The invention relates to a method of manufacturing a box-shaped building element in which on a first manufacturing site concrete mortar is poured and consolidated by vibrations or shocks in the cavity of a casting mould consisting of a lower profile gauge, a jacket, a core and an upper gauge and in which the resultant, incompletely cured casting is removed from the core or from the jacket and is transported together with the jacket or the core respectively to a second manufacturing site, after which the jacket or the core respectively is removed from the still incompletely cured casting.
Such a method is known from Dutch patent specification 48,210. In this known method the casting cannot be taken out of the casting mould until the concrete has sufficient resistance to deformation so that a comparatively retention time in the casting mould is required in order to avoid damage of the casting when it is taken out of the casting mould or thereafter.
The invention has for its object to avoid damage of the casting with a short time of residence in the casting mould. For this purpose the casting together with the upper gauge and the lower gauge is removed from the jacket or the core respectively, whilst at least the upper gauge is retained with respect to the casting with the aid of positioning means.
The invention relates to and provides in addition, a building structure such as a tunnel, sewer, culvert, composed of a sequence of joined building elements manufactured each by the method according to the invention.
The aforesaid and further features of the invention will be described more fully with reference to the drawing.
In the drawing show schematically

Figure 1 a display of the method in accordance with the invention,
Figure 2 an enlarged sectional view of detail II of Figure 1 in carrying out a preferred method in accordance with the invention,
Figure 3 an enlarged sectional view of detail III of Figure 1,
Figure 4 a building structure in accordance with the invention, in which the situation after a degree of settling in the ground is indicated by broken lines,
Figure 5 on an enlarged scale detail V of Figure 4,
Figure 6 a sectional view taken on the line VI-VI in Figure 5,
Figure 7 a variant of Figure 3,
Figures 8 and 9 each a further variant of Figure 2 and Figure 3 respectively, and
Figures 10 and 11 each a further variant of Figure 2 and Figure 3 respectively.

Figure 1 illustrates schematically the series manufacture of box-shaped building elements 3. On a first manufacturing site 1 concrete mortar 10 is poured from a container 11 into the cavity 4 of a casting mould 5 consisting of a lower profile gauge 6, a jacket 7, a core 8 and an upper profile gauge 9. During the uniform pouring of the concrete mortar 10 having the humidity of earth the casting mould 5 disposed-on a vibrating table 12 is subjected to vibrations or shocks to consolidate the concrete mortar 10. After the mould cavity 4 is filled, the upper profile gauge 9 is pressed against the concrete mortar 10 present in the mould cavity 4, whilst the concrete mortar 10 is further consolidated by means of a vibrating device 13 arranged in the upper gauge 9.
The vibrating table 12 is disposed in a cave 14 at a lower level than the factory floor 15 on springs 16 and provided with a vibrating device 17 and is guarded by means Of stop bolts 18 against excessive upward movements. The core 8 is detachably fastened by means of bolts 19 to the vibrating table 12.
From a stock 20 a lower profile gauge 6 is deposited around the core 8 on the vibrating table 12 and the jacket 7 is secured by bolts 21 to the lower gauge 6. A reinforcing network 22 is arranged in the mould cavity 4 as well as a number of pipes 24, for example, of synthetic resin, reserving each a passage for a pull rod 23. Each pull rod 23 is screwed by its lower end 25 into the lower gauge 6 and has a screwthreaded top end 26 with a square head 27 so that after the mould cavity 4 is filled and after the upper gauge 9 is disposed thereon said upper gauge 9 can be pressed home by nuts 28. The pull rods 23 with the nuts 28 constitute positioning means for retaining the upper gauge 9 with respect to the casting 33.
The core 8 is first removed from the resultant, incompletely cured casting 33 by pulling up the jacket 7 together with the lower gauge 6 and the upper gauge 9 and the pull rods 23 extending across the concrete mortar 10 of the casting 33 at eyelets 29 of the jacket 7 with the aid of an elevator crane 30, which conveys this assembly to a second manufacturing site 2 and deposits it with the lower gauge 6 on a floor 31. Then the jacket 7 is removed from the still incompletely cured casting 33 and from the lower gauge 6 and the upper gauge 9 retained therein by means of the pull rods 23 of the positioning means extending` across the concrete of the casting 33 by loosening the bolt connections 21 and by pulling up the jacket 7.
In a further stage, after disengaging the upper gauge 9 from the lower gauge 6 by unscrewing the pull rods 23 from the lower gauge 6 the upper gauge 9 is removed. After complete curing of the concrete of the building element 3 the lower gauge 6 is removed.
Finally, subsequent to hardening of the castings 33 for example, by means of steam in an autoclave (not shown) building elements 3 are obtained for composing a building structure 32 as shown in Figure 4, for example, a tunnel, a culvert, a duct or a similar structure consisting of a sequence of joined, box-shaped building elements 3.
The pipes 24 forming each a passage for a pull rod 23 and embedded at the corners 34 of the building elements 3 (Figure 5) can be used, in addition, for receiving stretching cables 35 to intercouple the building elements 3. These stretching cables 35 are anchored with bias tension at both ends of the tunnel 32 by means of cable anchors 36. The joints 37 (Figure 5) between the contiguous building elements 3 comprise a ring 38 at one building element 3 for engaging a groove 39 of the other building element 3, whilst the axial gap 40 accommodates an elastic sealing ring 41. It is thus possible to deposit the building structure 32 on a weak underground 42, which tends to subside, since the building elements 3 can turn relatively to one another whilst, however, the water tightness of the joints 37 is maintained.
By using the method according to the invention it is ensured that the joint surfaces of the building elements 3 which bound the gap 40 satisfactorily maintain their shape during moulding despite the fact that the castings 3 are stripped of the core 8 and the jacket 7 at an early instant so that they satisfactorily join one another.
The building elements 3 manufactured in accordance with the invention are generally reinforced by one or more reinforcing steel networks 43. The reinforcing networks 43 as shown in Figure 7 are disposed in a mould cavity 4 and the upper gauge 9 of the casting mould 5 is connected with said reinforcing networks 43 with the aid of connecting means 44 of the positioning means consisting of anchors 45 welded to the reinforcing networks 43 and placed in the mould cavity 4 and of a screw joint 46 for each anchor 45.
During the removal of the core 8 and the jacket 7 the reinforcing networks 43 prevent sagging of the non-cured concrete mortar 10, whilst the upper gauge 9 supports and holds in place the joint surfaces 47. Likewise the lower gauge 6 maintains the model of the joint surfaces 48 on the lower side. The connection between the lower gauge 6 and the casting 33 is automatically established since the casting 33 continues bearing on the lower gauge 6.
If a building element 3 does not require a reinforcing network 43, it may be advantageous for a simple, reliable and rapid manufacture to embed positioning anchors 49 in the casting 33 by which the upper gauge 9 is connected with the casting 3 and by which the occurrence of a crack 50 during the removal of the core 8 and the jacket 7 is avoided. The lengths of the anchors 49 are chosen so that the zones of imminent cracks 50 are bridged by the anchors 49. The anchors 49, moreover, satisfactorily transfer the vibrations of a vibrating device 13 arranged on the upper gauge 9 to the concrete mortar 10. The concrete mortar 10 of the lower end of the casting 3 is satisfactorily consolidated particularly by means of the vibrating device 17, whilst the vibrating device 13 particularly consolidates the upper concrete mortar 10, where the effect of the vibrating device 17 is reduced.
In the method illustrated in Figures 10 and 11 first the core 8 is removed from the casting 33 by pulling upwards the latter together with the lower gauge 6, the upper gauge 9 and the jacket 7 by eyelets 29. The upper gauge 9 is retained on the casting 33 provided with reinforcing networks 43, since it is pressed down on the concrete mortar 10 by screws 51 supported on the jacket 7 and forming positioning means. Figure 11 shows that subsequently at a second manufacturing site 2 the jacket 7 is removed, however, not until has the upper gauge 9 been positioned with respect to the lower gauge 6 with the aid of positioning means 52 extending in the box-shaped channel 53 of the casting 33 and consisting of posts 55 anchored in the floor 54 of the manufacturing site 2, said posts being provided at the top ends with pivotable, horizontal supports 56 having pressure screws 57 for pressing the upper gauge 9 against the concrete mortar 10 of the casting 33 so that the upper gauge 9 is positioned with respect to the casting 33 and with respect to the lower gauge 6 supporting said casting 33 and lying on the bottom 54.
Conversely, it is as an alternative possible to first remove the jacket 7, whilst the upper gauge 9 is retained by positioning means with the aid of the core 8 with respect to the casting 33, after which the core 8 is removed, however, not until has the upper gauge 9 been positioned with respect to the lower gauge 6 by means of posts extending outside the casting 33.

Claims

1. A method of manufacturing a box-shaped building element in which on a first manufacturing site concrete mortar is poured and consolidated by vibrations or shocks in the cavity of a casting mould consisting of a lower profile gauge, a jacket, a core and an upper gauge and in which the resultant, incompletely cured casting is removed from the core or from the jacket and is transported together with the jacket or the core respectively to a second manufacturing site, after which the jacket or the core respectively is removed from the still incompletely cured casting, characterized in that the casting together with the upper gauge and the lower gauge is removed from the jacket or the core respectively, whilst at least the upper gauge is retained with respect to the casting with the aid of positioning means.

2. A method as claimed in claim 1, characterized in that the upper gauge is connected by the positioning means with the lower gauge and the casting together with the upper and lower gauges interconnected by the positioning means is removed from the core and the jacket.

3. A method as claimed in claim 1, characterized in that into the mould cavity are arranged connecting members of the positioning means and the casting together with the upper and lower gauges interconnected by the connecting members then extending across the concrete of the casting is removed from the core and the jacket.

4. A method as claimed-in claim 3, characterized in that a number of pipes reserving each a passage for a con- .necting member forming part of the positioning means are arranged in the mould cavity.

5. A method as claimed in claim 3 or 4, characterized in that a reinforcement is arranged in the mould cavity for the building element and in that the upper gauge is connected with the reinforcement by means of connecting members of the positioning means.

6. A method as claimed in claim 1, characterized in that first the.core is removed whilst the upper gauge is retained by positioning means with the aid of the jacket with respect to the casting, after which the jacket is removed subsequent to positioning of the upper gauge with respect to the lower gauge by means of connecting members extending inside the box-shaped channel of the casting or in that first the jacket is removed whilst the-upper gauge is retained with respect to the casting by positioning means with the aid of the core, after which the core is removed subsequent to positioning of the upper gauge with respect to the lower gauge by means of connecting members extending outside the casting.

7. A method as claimed in anyone of the preceding claims, characterized in that the upper gauge is pressed against the concrete mortar present in the mould cavity and the concrete mortar is consolidated by means of a vibratory device arranged on the upper gauge.

8. A building structure e.g. tunnel, sewer, culvert, composed of a sequence of contiguous building elements manufactured each by a method as claimed in anyone of the preceding claims.

9. A building structure as claimed in claim 8, characterized in that the passages of the building elements manufactured by the method claimed in claim 4 are in line with one another and receive stretching cables for intercoupling said building elements.