GB2363110A

GB2363110A - Method of constructing a lift shaft.

Info

Publication number: GB2363110A
Application number: GB0006472A
Authority: GB
Inventors: Wayne Toghill
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-03-18
Filing date: 2000-03-18
Publication date: 2001-12-12
Anticipated expiration: 2020-03-18
Also published as: GB2363110B; GB0006472D0

Abstract

A lift shaft is prefabricated in reinforced concrete sections 10, 12 which are stacked one upon another. Each section has four integrally-formed sides 1-4. The sections include alternate door sections 10 and shorter spacer sections 12, the door sections having a rectangular door aperture 6 formed in one side. The opposed top and bottom faces of the stacked sections are provided with projecting bars 14 and sockets 16. The sections are formed by moulding within inner and outer shuttering secured to a vibrating table.

Description

1 2363110 LIFT SHAFTS

TECHNICAL FIELD OF THE INVENTION

This invention relates to the construction of lift shafts in buildings.

BACKGROUND

During the construction of new buildings lift shafts are normally constructed in situ by bricklayers using concrete building blocks. Apart from being timeconsuming and incurring high labour costs, each time a course of blocks is laid there is inevitably a small deviation from vertical. The effect is cumulative so that even in the case of a three storey building having about 40 courses of blocks there is likely to be a significant deviation from vertical over the height of the shaft. There have been instances where this has resulted in the shafts having to be demolished and rebuilt, causing additional delay and expense.

The present invention seeks to provide a new and inventive way of constructing lift shafts..

2 P953 SUMMARY OF THE INVENTION

The present invention proposes a method of constructing a lift shaft in which the shaft is prefabricated in reinforced concrete sections which are stacked one upon another.

The invention also provides a lift shaft formed of prefabricated reinforced concrete sections which are stacked one upon another.

Each section preferably has four integral ly-formed sides. The opposed top and bottom faces of the stacked sections are preferably provided with locating means. Such locating means may take various forms, e.g. cast projections and recesses. The projections could be cast in concrete or they may be projecting rods or the like.

In a preferred form of the invention the shaft sections include alternate door sections and spacer sections. The door sections may have a rectangular door aperture formed in one side whereas the spacer sections will generally have four solid walls. The height of the door sections will normally be greater than the height of the spacer sections.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description and the accompanying drawings referred to therein are included by way of non-limiting example in order to illustrate how the invention may be put into practice. In the drawings:

I 3 P953 Figure 1 is a general view of part of a lift shaft constructed of prefabricated sections in accordance with the invention; Figure 2 is a general view of formwork for use in constructing one of the sections; Figure 3 is a detail of the formwork; and Figure 4 shows an nother part of the formwork in detail.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring firstly to Fig. 1, the lift shaft is formed of prefabricated door sections 10 and spacer sections 12.

The door sections 10 are about 2.2 metres high and are rectangular in plan view with four side walls 1, 2, 3 and 4, each about 100 mm thick. One of the side walls 1 is formed with a vertical door opening 6. A row of steel bars 14 project vertically from the top face of each of the side walls 1-4 whereas the bottom face is formed with a row of complimentary sockets such as those indicated at 16.

The spacer sections 12 are similar to the door sections 10 except that they are shorter than the door sections and contain no door apertures. The wall sections again have vertically projecting bars 14 (some of which have been omitted for convenience) and downward ly-facing sockets 16.

4 P953 In the construction of a new building a reinforced concrete foundation slab is first laid at the lowest level of the building. A door section is lowered onto the slab and bedded on mortar. A thin layer of grout is then laid onto the top faces of the walls 1-4 and a spacer section 12 is lowered onto the door section and carefully positioned such that the bars 14 of the door section locate within the complimentary sockets 16 of the spacer section 12. The combined height of one door section and one spacer section is equal to the height of a single floor so that, for a three storey building, a total of six sections will be required, i.e. three door sections alternating with three spacer sections. Provided the base slab is level and the bottom section is checked for vertical the shaft will also be vertical to within acceptable tolerances. The time taken to construct a shaft and the number of manhours involved is considerably reduced.

Fig. 2 shows formwork for use in constructing the shaft sections. The formwork includes inner and outer right-angle shuttering plates 20 and 21 which are mounted in adjustable positions on a vibrating table 22. Each side of the shuttering has an adjustable gap 24 which is bridged by a pair of spaced inner and outer side plates which slide into the gap by means of tongue and groovejoints, dovetailjoints, or head and socketjoints as shown in Fig. 3. Thus, by adjusting the position of the corner plates 20 and 21 on the table and using side plates of an appropriate width, the size of the formwork can be adjusted to mould shaft sections of different widths.

The joints between the side plates and the external corner plates 21 are held together by screw threaded bars 32, which extend between brackets 33 and 34 secured to the corner plates. The bars carry nuts which are P953 tightened to bear against the outer faces of the brackets. There are typically three such bars on each side of the formwork.

The door openings are formed by closing the opposed vertical edges of one of the gaps 24.

Upstanding moulding cores 26 (e.g. of plastics) are slidably mounted in grooves in the table 22, and steel mesh is inserted between the inner and outer plates. Concrete is then poured into the space between the plates and the table is vibrated to settle the concrete. Prior to setting, the reinforcing rods are inserted into the concrete to project above its upper surface, held by rubber bushes inserted into locating members 36 which fit over the top of the shuttering plates as shown in Fig. 4. When the concrete has set the shuttering is removed so that the sections can be transported to site. The cores 26 are drawn out of the set concrete to form the sockets 16.

Claims

It will be appreciated that the features disclosed herein may be present

in any feasible combination. Whilst the above description lays emphasis on those areas which, in combination, are believed to be new, protection is claimed for any inventive combination of the features disclosed herein.

CLAIMS P953 1. A lift shaft formed of prefabricated reinforced concrete sections which are stacked one upon another.
2. integrally-formed sides.

A lift shaft according to Claim 1, in which each section has four
3. A lift shaft according to Claim 1 or 2, which the opposed top and bottom faces of the stacked sections are provided with locating means.
A lift shaft according to Claim 3, in which said locating means includes cast projections and recesses.
5. A lift shaft according to Claim 3 or 4, in which said locating means includes projections formed by projecting bars and cast sockets.
6. A lift shaft according to any preceding claim, in which the prefabricated sections include alternate door sections and spacer sections.
7. A lift shaft according to Claim 6, in which the door sections have a rectangular door aperture formed in one side.
8. A lift shaft according to Claim 6 or 7, in which the spacer sections have four continuous walls.

7 P953
9. A lift shaft according to Claim 6, 7 or 8, in which the height of the door sections is greater than the height of the spacer sections.
10. A method of constructing a lift shaft in which the shaft is prefabricated in reinforced concrete sections which are stacked one upon another.
11. A method according to Claim 10, in which the sections are prefabricated in formwork which includes inner and outer shuttering fixed to a vibrating table.
12. A lift shaft substantially as described with reference to the drawings.
13. A method of constructing a lift shaft substantially as described with reference to the drawings.