AU631851B2 - Adjustment arrangement for tilt-slab construction - Google Patents

Description

631851 COMPLETE SPECIF I CATI N FOR OFFICE USE Application Number: Lodged: Class: Int. Class: Complete Specification Lodged: Accepted: Published: Priority: Related Art: TO BE COMPLETED BY APPLICANT Name of Address Address Applicant: of Applicant: for Service: Gardith Engineering Pty. Ltd.

2/41 Christensen Street, Cheltenham, Victoria, 3192 SMITH SHELSTON BEADLE 207 Riversdale Road (P 0 Box 410) Hawthorn Victoria 3122 Australia (Attorney Code SA) Complete Specification for the invention entitled: i 1 j ADJUSTMENT ARRANGMENT FOR TILT-SLAB CONSTRUCTION The following statement is a full description of this invention, including the best method of performing it known to me/us: Page 1 Our Ref: #2917 JC:JH 2 This invention relates to tilt-slab construction methods, and in particular relates to a method and apparatus for connection of elements to upright slabs.

In tilt-slab construction, reinforced concrete walls are poured in situ, in a horizontal mould. Thereafter, they are raised to an appropriate position. As part of the moulding process, various elements are located such that in the cured slab, they may be used for the attachment of support props, or other elements used in the erection process.

Clearly, such elements have to be precisely located in order to be of use.

Even an error of a few centimetres means that in the erected slab, the element cannot be used. It is common for such errors to occur.

It is an object of this invcntion to provide an improved apparatus and method for use in tilt-slab construction.

The invention provides an element adapted to be located in a slab mould for incorporation into a slab, said element including a keyway adapted for subsequent location of a fastening device, at least part of said keyway being occupied by a material which is adapted to be subsequently removed.

An embodiment of the invention, will be described in detail hereinafter in relation to the accompanying drawings, in which:- Fig. 1 is a perspectix e view of a locating element; Fig. 2 is a top plan view of the clement of Fig. 1; Fig. 3 is a side elevation of the element of Fig. 1; Fig. 4 is. an end elevation of the element of Fig. 1; Fig. 5 is a side elevation of the locating element of Fig. 1 in situ in a concrete slab; 2 tFig. 6 is a front elevation of a locating plate; and Fig. 7 is a side elevation of the plate of Fig. 6.

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Jcspe. 020/gard i th 1 October, 1992 i ar~- 3 -3- Locating element 110 has a front plate 112 and a rear channel element 111.

Preferably the clement 110 is formed from steel and is fabricated by welding U-section rear portion 111 having base 113 and sides 126, 128 to plate 112 as shown at 130 in Fig. 3 For connection into a concrete slab 116, reinforcing elements 114 may be loca td on the rear face 115 of element 110. As shown in Fig. 1, there may be two straight reinfor ement rods. Alternatively, there may be two U-shaped reinforcement rods. The timing, number and manner of connection of rod(s) 114 to element 110 is a matter of choice, as is the use of alternative methods to locate element 110 in slab 116. It is clearly convenient to have the element 110 firmly located in position, by attachment to reinforcing rod (114) or mesh, prior to pouring of the slab 116, and the element is intended to be located, as shown in Fig. 5, in the completed slab, with front surface 118 flush with surface 119 of slab 116. However, the element 110 may be located in a spaced relationship with slab reinforement such as reinforcing mesh.

Located in element 110 is a slot 120, which extends almost the full length of plate 112. At one end of slot 120 is an enlarged pcrtion 122 which is dimensioned to receive part of a connecting element, such as the head 125 of a bolt 124 (Fig. 5) and which imparts a 'keyhole' shape to slot 120.

Plate 112 preferably has the dimensions 300mm long x 84mm wide x 12mm thick, and is formed from AS1204/350 material. The slot 120 is preferably 275mm long by 25mm wide with portion 122 having a preferred diameter of 48mm. Portion 111 is preferably formed from cold formed steel section, having the internal measurements 42mm wide x 40mm deep x thick.

Slot or keyway 120 communicates with the interior -pace 121 of channel 6 September, 1992 4 portion 111. This space 121 (and the slot 120 as well, if desired) is filled with a material 123 capable of being subsequently dissolved with a solvent. A preferred material 123 is polystyrene foam, which may be dissolved by trie application of the solvent petrol. The space 121 is so filled in order to prevent the ingress of wet concrete when the element 110 is located in a form or the like and concrete is poured therearound.

Element 110 should be considered as a module, and a number of such elements could be located in a slab, by attachment to reinforcing rod, mesh or the like in desirable positions. They may be located ear to one another, or not.

If a relatively close array were desired, it may also be desirable to have an intermediate plate extending between plates 112.

Locating plate 132 also has a generally cuboidal body 134 with generally parallel longitudinal slots 136. Locating plate member 132 is adapted to be connected to a prop, column, beam or any other constructional element for attachment to erected slab 116. The plate is preferably used in a substantially vertical orientation. It is preferably formed from a metal such as steel.

The apparatus of the embodiment of Figs. 1 to 5 of the invention is operated as follows:- Before or after the slab 116 has been erected, when the concrete thereof has at least partially cured, a solvent may be used to dissolve the material in slot 120. Bolts 124 (preferably two, but any number may be used within spatial constraints) are located in slot 120, with head 125 entering through enlarged portions 122 to locate behind slot 120.

Thus, when a constructional element bearing a plate member 132 is sought to be connected to element 110, the threaded ends of bolts 124 may pass through apertures 136, thus providing means for adjusting the relative positions h B soptmbtr. 1992 5 of clement 110 and member 132 in two dimensions. Once in the desired relative position, nuts are used to secure the members 110,132 together.

It can be seen that members 126 may be located without absolute precision in a slab mould, whilst allowing for precise final location of props, beams, columns or the like on the erected floor or wall slab.

Element 110 may be used in conjunction with similar elements to provide an array of such elements attached to reinforcing rod, mesh or the like which can have the elements 110 close together in which case a further plate may be connected between adjacent elements, or located further apart.

Tests have been carried out by Monash University on the strength of the element 110 (referred to by Monash as a 'concrete insert keyway').

The aim of the tests was to determine the force required to pull out the concrete ins-t. keyway for different angles of inmlination of the force to the normal of the face of the specimen.

It was found that a mean load of 49.1 KN was required to pull out the element 110 at 00, 50.0 KN at 30°, 76.2 KN at 60° and 205 KN at 900 (shear test).

It can be seen that the present invention provides an improved means for locating integers in a tilt-slab construction process.

The entire contents of the provisional specification lodged with Australian Patent Application of which this is the complete specification is hereby imported into this specification and forms part of the disclosure of this specification. The claims form part of the disclosure of this specification.

Jcspc. 020/gard1h 0 Sptembeor. 1992 c- ~I~

Claims (9)

1. An element adapted to be located in a slab mould for incorporation into a slab, said element including a keyway adapted for subsequent location of a fastening device, at least part of said keyway being occupied by a material which is adapted to be subsequently removed.

2. An element according to claim 1, wherein said material is an adhesive, plastics (including foamed thermoplastics) or like material which is capable of being dissolved by a solvent, or is otherwise removable.

3. An element according to claim 2, wherein the material is removed by the application of heat.

4. An element according to any preceding claim wherein said keyway has an enlarged portion to receive portion of said fastening device.

An element according to any preceding claim, wherein the keyway is keyhole-shaped, the fastening device is a bolt and the portion is the head of said bolt.

6. A locating device for tilt-slab construction, including an element according to claim 5, and a locating plate provided with at least one slot, which is adapted to receive the other portion of said bolt.

7. A tilt-slab construction process including the steps of casting into a slab an element according to any one of claims 1 to 5, removing said material from said keyway, locating a fastening device in said keyway, passing portion of said fastening device through a slot in a locating plate, which locating plate is attached to another integer.

8. A tilt slab construction process, substantially as herein described with reference to the accompanying drawings.

9. An element for use in tilt-slab construction, substantially as herein th 8 Soptc.mbr. 1992 7 described with reference to Figs. 1 to 5 of the accompanying drawings. A locating arrangement for use in tilt-slab construct:an systems, substantially as herein described with reference to Figs. 1 to 7 of the accompanying drawings. DATED this 8 September, 1992 CARTER SMITH BEADLE Fellows Institute of Patent Attorneys of Australia Patent Attorneys for the Applicant: GARDITH ENGINEERING PTY. LTD. Jcspe.020/gard th a Soptoember. 1992 u c