GB2485792A

GB2485792A - Structural fixing element for embedding into concrete

Info

Publication number: GB2485792A
Application number: GB201019864A
Authority: GB
Inventors: Paul Butler
Original assignee: Wincro Metal Industries Ltd
Current assignee: Wincro Metal Industries Ltd
Priority date: 2010-11-24
Filing date: 2010-11-24
Publication date: 2012-05-30
Also published as: GB201019864D0

Abstract

The structural fixing element 10 comprises an elongate channel section comprising sidewalls inclined such that they converge towards each other and each defining an inwardly turned lip the space between the lips defining a slot. The fixing element also includes a T-head bolt including a portion at one end of its head which is not wider than the slot. In use the bolt may be inserted into the channel and rotated through a quarter turn such that a pair of abutment elements 28 enter into an overlying relationship with the in turned lips. The channel section preferably includes a rear face with a number of wrinkly or corrugated tang elements 12 which act as anchors to firmly root the fixing element into concrete in which the tang elements are embedded. A pair of tang elements may be made from a single metal strip which is bent to form two right angles and then passed through two slits 16 within the rear face of the fixing element.

Description

Structural fixing The invention relates to a structural fixing for use mainly in the building industry.

It is common practice in the building industry to use specialised elongate channel section and bolt fixings, the channel being adapted to be cast into or otherwise attached to a building structure, to provide a positive anchorage for securing components and building elements. The use of such fixings often eliminates the need for the costly and time consuming procedure of on-site drilling of either concrete or steelwork. The use of T-}Iead bolts, which can be located to extend through an open slot between inturned lips of the elongate section, provide a very convenient and secure anchorage means at any required point along the length of the channel section.

When the channel sections concerned are provided for casting into the concrete of the building structure they will usually be provided with wrinkly tang elements at intervals along their length so that, when the concrete has completely set, the sections are permanently rooted in the structure. Also, when provided for casting into the concrete of the building structure, the sections are generally filled, by the manuficturer, with expanded polystyrene to prevent the ingress of concrete during the casting process. Before 1-Head bolts can subsequently be entered into the channel sections, which then form an integral part of the building structure, the expanded polystyrene has to be scraped or abraded away to allow the 1-Head of a bolt to be entered into the slot of the channel section. This can usually be effected quite easily, but on occasions it is found that the expanded polystyrene has not formed a perfect seal against the ingress of cement into the channel section. When this has occured, the leakage is usually found to have resulted in unwanted traces of difficult to remove concrete in the corners between the inner wall and the side surfaces of the channel. The clearing of such unwanted traces of concrete from channels forming part of a building structure, by a tool inserted through the slot between the inturned lips of the channel, can seriously delay the subsequent installation of other parts and fitments of the building structure.

According to the invention, there is provided an elongate channel and 1-Head bolt assembly, the assembly including, in combination, a channel section having side walls inclined so that they converge towards a point where they are turned inwards to form inturned lip elements defining a slot in the channel, and at least one T-Head bolt an upper portion of the head of which is no wider than the slot in the channel section so that, in use, there are formed spaces within the channel, at the widest part of the section, to which a leakage of concrete may be of no detriment.

In the accompanying drawings, which illustrate, by way of example only, a particular embodiment of the invention Figure 1 is a perspective view of a channel section forming part of a structural fixing embodying the invention, Figure 2 is an end view of the channel section when cast in concrete and forming part of a building structure under construction, with a 1-Head bolt about to be inserted into said channel section, Figure 3 is a view similar to Figure 2 but showing the bolt to have been properly located in the channel section, Figure 4 is a sectional view, on the line 4-4 in Figure 3, and Figure 5 is a scrap view of a channel section showing signs of cement leakage.

Referring now to Fig. 1, the channel section there illustrated, and generally indicated 10, is shown to be provided at its rear face with wrinkly tang elements 12 by means of which it can be very firmly rooted in the concrete of a building structure. It will be understood that the channel section is of indeterminate length, being decided according to the position in which it is to be used, and the number of tang elements required are therefore variable.

However, the tang elements shown in Fig. I are a connected pair formed from a single length of metal stripl4 the opposite ends of which have been turned through a right angle to extend through spaced slots 16 formed in the rear wall of the channel section, before being tack welded in position at 18 and formed into their wrinkly shape.

Referring now in particular to Fig. 2, the channel section is shown to have side walls 18,18 which converge towards points where they are each turned inwards, that is to say towards each other, to form inturned lip elements 20,20 defining a slot 22. A T-Head bolt, generally indicated 24, the head 26 of which is about to be entered into the section through the slot 22, is provided for use with the elongate channel section just described. As shown, the head of the bolt in this view is the same width as its screwthreaded part, and the slot 22 defined by the inturned lips of the side walls of the elongate section is just wide enough for the bolt head to be entered into it. As shown in Figs. 3 and 4. the head 26 is provided, in a plane at right angles to the plane in which Fig. 2 is drawn, with abutment elements 28,28 so that, when it has been entered fully into the elongate channel section, the bolt can be rotated to bring said abutment elements into overlying relationship with the inturned lip elements 20,20 of the channel section. As shown in Fig. 4, a corner of each abutment element 28 is cut away at 30 to enable the bolt to be rotated through the quarter turn required to bring it to the position in which it is located for use.

As shown in Fig. 3, when the bolt has been entered fully into the channel section, the head of the bolt is shown just touching the length of metal strip the opposite ends of which form the wrinldy tang elements. There will in practice be provided a very small degree of free movement between the two..

In Fig. 5 there is illustrated the degree of leakage which could, by use of the invention, be tolerated at any location along the length of the channel section where there had been an imperfect application of expanded polystyrene. This is much more than usually found in such a case; it has in the past been quite usual to find that a very small leakage of concrete into the elongate section has been -5'.-sufficient to prevent the complete insertion of a T-Head bolt at a required location.

Thus there is provided an elongate channel and 1-Head bolt combination which it is thought will avoid the need to remove the results of many instances of cement leakage into such channels. If the leakage is relatively small it will in many cases be contained in the space available in the assembled combination described above.

Various modifications may be made. For example, the upper part of the bolt head could be of tapering shape to provide even more free space for cement leakage to be tolerated.

Claims

Claims 1. A structural fixing constituted by an elongate channel section and at least one T-Head bolt, the elongate channel section having side walls inclined so that they converge towards a point where they are turned inwards to form inturned lip elements defining a slot in the channel, and the at least one T-Head bolt an upper portion of the head of which is no wider than the slot in the channel section so that, in use, there are formed spaces within the channel, at the widest part of the section, to which a leakage of concrete may be of no detriment.
2. A structural fixing according to claim 1, in which the head of the bolt is provided, in a plane at right angles to the plane in which it can be entered into the channel section, with abutment elements so that, when it has been entered Ihily into said channel section, it can be rotated to bring said abutment elements into overlying relationship with the inturned lip elements of said channel section.

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3. A ctural fixing according to claim 2, in which a corner of each * : abutment element is cut away to enable the bolt to be rotated through the nsO * quarter turn required to bring it to the position in which it is located for use. *. ** * * * * S S. S

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4. A structural fixing according to any one of the preceding claims, in which the channel section is provided at its rear face with a plurality of wrinldy tang elements by means of which it can be firmly rooted in the concrete of a building structure.
5. A structural fixing according to claim 4, in which the wrinldy tang elements are provided in connected pairs, each pair being formed from a single length of metal strip the opposite ends of which have been turned through a right angle to extend through spaced slots formed in the rear wall of the channel section.
6. A structural fixing including, in combination, an elongate channel section and T-Head bolt assembly constructed, arranged and adapted to be used substantially as hereinbefore described with reference to and as illustrated by the accompanying drawings. * ** ***** * . * ****.. * * * * * ** ** * * * * * ** * * S * * S.