GB2098654A - Building construction - Google Patents

Abstract

In a method and apparatus for casting concrete structures and employing climbing shuttering, an upright support 13 on which is mounted a crawler 10 is spaced from the structure, and the support is held stationary whilst the crawler is actuated in one mode to climb on the support, or the crawler is held stationary whilst it is operated in another mode to cause the support to climb on the crawler. The support is held stationary by resting its base 15 on the ground or by supporting it on a bracket 18 fixed to its base and to the structure. The crawler is held stationary by connecting shuttering 11 extending from it to the structure. <IMAGE>

Description

SPECIFICATION Building construction This invention relates to building construction.

In the construction of high-rising poured concrete walls spaced apart shuttering has been mounted on a foundation and when the first course of concrete has sufficiently hardened moved upwardly step by step by crawlers running on supports fixed to nuts embedded in the hardened portion of the wall.

Although it has been proposed to move the shuttering downwardly (see US Patent Specification No.

4 040 774), this has not been used in practice as the crawler could not be caused to move down with the same ease as it moves up.

For the known system (see also S.A. Patent No.

78/2842) it is essential to have vertical supports secured to a hardened part of the wall and extending above the crawlers so that the latter can crawl up the vertical supports. One face of each vertical support provides a shuttering surface and has to be made continuous with the rest of the shuttering. The shuttering system used thus has to be designed to suit the crawler system.

An object of the invention is to provide a crawler system which is substantially independent of the choice of shuttering system.

The invention provides a method for the construction of a structure employing a climbing technique in which a crawler is operable in either of two modes to cause relative climbing movement between the crawler and a support on which it is mounted, including the steps of spacing the support at all times from the structure, of holeing the support stationary while operating the crawler in a first mode in which it climbs on the support, and of holding the crawler stationary while operating the crawler in a second mode in which the support climbs on the crawler.

In a preferred form of the invention, the method includes the step of holding the crawler stationary by connecting a part extending from it to the structure.

The support may be held stationary by resting it on the ground or by supporting it on a bracket fixed to the base ofthe support and to the structure.

The invention also provides an apparatus for use in the construction of a structure employing a climbing technique includi g an upright support, crawler mounted on the support and operable in either of two modes to cause relative climbing movement between the crawler and the support, means to hold the support stationary while the crawler is operated in one of its modes in which it climbs on the support, and means to hold the crawler stationary while it is operated in its second mode in which the support climbs on it, the means also serving in eaih case to space the support from the structure.

A prop of adjustable length may be connected pivotally at its upper end to the upper end of the support and at its lower end to the base of the support. Variations in the length of the prop may then serve to vary the attitude of the support, allowing for variations in the verticalicy of the structure.

The apparatus may include tracks on opposite sides of the support for the crawler, a mechanism in the crawler operazle to cause the crawler to ascend quickly along one track and another mechanism in the crawler operable to cause the crawler to descend quickly on the other track.

In the accompanying drawings: Figure 1 is a view showing a crawler device according to the invention in its position on the ground.

Figure 2 shows the first step in getting off the ground, and Figure 3 shows the device lifted off the ground.

In the illustrated embodiment, a crawler 10 carries a shutter 11 by means of horizontally arranged screw jacks 12. The shutter is reinforced by horizontally extending walers 20 on vertical members 30.

The crawler 10 is mounted on a vertical support 13, which is in the form of an I-section structural member which has spaced cut-outs in the web of the l-section. The web forms tracks for the crawler to climb on. The lower end of the support 13 is pivotted at 21 to a base 15 which extends laterally. The upper end of the support 13 has pivotted to it a bar 17, and a strut 16 is pivotted at its upper end to the bar 17 and at its lower end to the base 15. The strut is of adjustable length by virtue of a turnbuckle 22 between its ends.

The operation of the apparatus described is as follows: Initially, the base 15 is laid on the ground, as shown in Figure 1.An identical apparatus would probably be positioned as a mirror image of the illustrated apparatus in a case where it is desired to use the apparatus for building, say, a slender wall. It is not necessary that there be a mirror image on the opposite side, however. If there is a mirror image, the shutter 11 is connected to its opposite number by ties shown at 23 in dotted lines. If there is no mirror image, the shutter 11 is connected to the steel reinforcement. The ties which are used for connecting the shutter 11 are left behind in the concrete after it has set.

Concrete is now poured behind the shutter 11.

When it has set to a sufficient extent, the shutter 11 is released either from its opposite number or from the reinforcement, the ties being left in the fresh concrete. The screw jacks are then operated to withdraw the shutter 11 from the concrete face, and the crawler 10 is operated in a mode in which it climbs up the support 13. In practice, when a chimney or like structure is being constructed, there will be number of supports 13 around the perimeter of the structure, and each of their associated crawlers would be operated at the same time to raise the shutters all around the structure. Following the operation of the crawler 10 the apparatus will be in the position illustrated in Figure 2.

The screw jacks 12 are again operated to push the shutter 11 to a position in which it is flush with the previously poured concrete face. Once again the shutter 11 is tied back, either to its opposite number or to steel reinforcement. A further quantity of concrete is poured behind the shutter 11, and allowed to set.

Once the concrete is sufficiently hard, the crawler 10 is operated in another mode in which it climbs down relative to the support 13. Since the shutter is fixed, however, the support will climb on the crawler to the position illustrated in Figure 3. Until this time, the support has been supported by virtue ofthe base 15 resting on the ground. Once the support 15 is off the ground, it is necessary to provide a further form of support for it.

This support is provided in the form of a bracket shown generally at 18 in Figure 3. The bracket 18 is fixed to the underside of the base 15 and to ties which have been left behind in the structure during a previous concrete pour. The shutter 11 is released and the crawler 10 once again operated in the mode in which it climbs up the support 13 with its shutter.

The steps described can be continued until the structure reaches the desired elevation. Throughout the process, it will be seen that the support 13 is independent of the structure, since it is spaced from the structure at all times by virtue of the shutter 11 and the bracket 18.

Although the apparatus has been described with particular reference to its applicability to lifting shuttering for successive pours of concrete, it will be realised that it could equally be used for raising other items on a previously co structed section of the structure, with a suitable part in place of the shutter 11 which can be tied back afterthe crawler has climbed up the support. For example, it would be possible to raise a working platform up a previously constructed wall. In a typical case, it would be possible to have a leading apparatus as illustrated for actually constructing the structure, and a following apparatus for raising men and materials. The follow ing apparatus could either use the same ties as the leading apparatus, if it is following in the same vertical line, or it could be staggered to the side of the leading apparatus, a short distance behind it.

The illustrated embodiment makes use oftwo spaced crawler boxes each housing two pawls 14, and linked by a double acting ram. This arrangement allows the crawler 10 to ascend with the shutter 11 during construction of the structure, and to descend with it when the structure is completed. In order for the crawler 10 to descend, the bracket 18 is secured to the structure as described, and the shutter released. The crawler is then operated in the mode in which it climbs down the support. The shutter is then tied back by means of the ties left in the structure and the bracket released. The crawler 10 is then operated in the mode in which it climbs up the support so that the support descends. This sequence of operations is continued until the whole apparatus is once again resting on the ground on the base 15, the bracket 18 having been removed prior to the last crawler operation.

This facility can make it unnecessary for there to be a crane to lower the shutter back to the ground on completion of the construction.

Claims (19)

1. A method for the construction of a structure employing a climbing technique in which a crawler is operable in either of two modes to cause relative climbing movement between the crawler and a sup port on which it is mounted, including the steps of spacing the support at all times from the structure, of holding the support stationary while operating the crawler in a first mode in which it climbs on the support, and of holding the crawler stationary while operating the crawler in a second mode in which the support climbs on the crawler.

2. A method according to claim 1, including the step of holding the crawler stationary by connecting a part extending from it to the structure.

3. A method according to claim 1 or claim 2, including the step of holding the support stationary by resting it on the ground or by supporting it on a bracket fixed to the base of the support and to the structure.

4. A method according to any one of the preceding claims, including the step of releasing the support prior to operating the crawler in its second mode.

5. A method according to any one of the preceding claims, including the step of releasing the crawler prior to operating the crawler in its first mode.

6. A method according to any one of claims 2 to 5, including the step of holding the crawler stationary by connecting shuttering extending from it to the structure.

7. A method according to any one of claims 2 to 6 in which the bracket is fixed to lost ties left behind previously in the structure.

8. A method according to any one of the preceding claims, including the step of varying the attitude of the support by varying the length of a prop operating between the upper end of the support and the base of the support.

9. An apparatus for use in the construction of a structure employing a climbing technique including an upright support, a crawler mounted on the support and operable in either of two modes to cause relative climbing movement between the crawler and the support, means to hold the support stationary while the crawler is operated in one of its modes in which it climbs on the support, and means to hold the crawler stationary while it is operated in its second mode in which the support climbs on it, the means also serving in each case to space the support from the structure.

10. An apparatus according to claim 9, in which the means to hold the support stationary includes a bracket fixed to the base of the support and adapted for connection to the structure.

11. An apparatus according to claim 9 or 10, in which the means to hold the crawler stationary is a part extending from the crawler for connection to the structure.

12. An apparatus according to claim 11, in which the part is shuttering.

13. An apparatus according to any one of claims 9 to 12, in which the bracket has means for engagement with lost ties left behind previously in the structure.

14. An apparatus according to any one of claims 10 to 13, in which the support is connected pivotally to its base, and a prop of adjustable length is connected pivotally to the support at its upper end and to the base at its lower end, variations in the length of the prop serving to vary the attitude of the sup port.

15. An apparatus according to any one of claims 12 to 14, including screw jacks connecting the shuttering to the crawler and operable to vary the spacing between the shuttering and the crawler.

16. An apparatus according to any one of claims 9 to 15, including tracks on opposite sides of the support for the crawler, a mechanism in the crawler operable to cause the crawler to ascend quickly along one track and another mechanism in the crawler operable to cause the crawler to descend quickly on the other track.

17. An apparatus according to claim 16, in which the support has an Section, and the tracks are provided by spaced cut-outs in the web of the section.

18. A method for the construction of a structure, substantially as herein described with reference to the accompaying drawings.

19. An apparatus for use in the construction of a structure, substantially as herein described with reference to the accompanying drawings.