INSERT FOR A CHANNEL SECTION MEMBER

Abstract: An elongate, expanded polystyrene insert is adapted to be fitted into a channel-section member to prevent the ingress of material such as concrete during construction work. The insert comprises a central section (28) adapted to fit into the open portion of the channel-section member (12) and two second elongate portions (30) attached to the central portion (28) which are adapted to be received within the channel-section member beneath respective elongate overhanging lips (18, 20). The central portion (28) and the two second elongate portions (30) are separated by respective elongate slots (32), which, in use, extend past the respective lip (18, 20) towards the base of the channel-­ section member. Such an insert may be slid into the channel-section member and prevents the ingress of, for example, concrete during construction work. After the concrete has set, the insert may be easily removed by slitting along each elongate slot to remove the central portion (28) of the insert, and the remaining second portions (30) positioned beneath each lip may then be easily removed.

Description: The present invention relates to inserts for a channel section member, and in particular, but not exclusively, to inserts which are only temporarily inserted in a channel section member (DE-U-8504883). In a building, it is often necessary to provide a frame work or support structure which is adapted to act as support for various structures, such as cable racking to carry cables, suspended ceilings or modular floors. Sometimes such frameworks or support structures rest on a solid floor or are suspended from a secure overhead point, such as a roof beam. However, it is sometimes desirable to secure some elements of the framework or support structure to a wall. If this is done in the early stages of constructing the building, when concrete is being poured, it is possible to hold the frame member in position and form the concrete around the frame member, such that when the concrete has hardened the frame member will be set into the concrete and securely affixed therein. Frequently, the frame members which are set into concrete are channel section members into which other elements of the framework or support structure are to be fitted at a later time. In order to prevent the ingress of concrete, such channel section members are provided with elongate inserts, often constructed of expanded polystyrene or polyurethane foam. Frequently, this is done merely by pressing in several lengths of the foam into the open face of the channel-section member and upon setting of the concrete the polystyrene foam may then be removed. However, the above-described polystyrene foam inserts are not particularly suitable for channel-section members having two opposed, overhanging elongate lips onto which other frame members are to be secured at a later date. If the foam insert is to be pressed into the open face of the channel section member, then its width will be equal to that of the aperture between the lips in the open face, and in particular, the insert will not extend into that region of the interior of the channel-section member underneath the elongate lips. Thus, it often happens that concrete finds its way into these voids, fouling the securing surfaces of the elongate lips resulting in poor securing of other framework members to the member attached to the wall. One way around the above problem is to provide an insert whose cross section is shaped complementarily to that of the channel-section member, such that the voids previously left under the overhanging lips is filled. In order to insert the inserts, it is merely necessary slide one or more of them longitudinally along the channel-section member to be secured. Such a shaped insert works very well to keep concrete away from the securing surfaces of the overhanging lips of the channel-section member. However, whereas previously it was possible merely to pull out the insert when the concrete had set, it is necessary to dig out the shaped insert, for example with a knife, since the portions of the insert underneath the overhanging lips prevent the insert from being pulled clean out of the apertured face of the channel-section member. Moreover, at this stage, the ends of the frame member are normally encased in concrete, so that it is not possible to slide the inserts out longitudinally. The removal of the inserts is necessary in order to allow the insertion of other frame members or frame securing members, and also the material used (expanded polystyrene foam) is normally highly flammable, and so must be removed for safety. Removing the insert by hand is a time-consuming process, and it is found that a quick, but extremely dangerous, alternative is to set the insert alight, possibly assisted by an inflammable liquid such as petrol. It can be appreciated that this is a very dangerous practice, but it is one which occurs due to the length of time it takes for inserts to be removed. It is an object of the present invention to provide an elongate insert for temporary insertion into an elongate, lipped channel-section member which is shaped to minimise the ingress of concrete if the channel-section member is being set into concrete, but which may also be rapidly, easily and safely removed. In accordance with the present invention, an elongate insert for insertion into an elongate, open, channel-section member having at least one elongate lip overhanging its base comprises a first elongate portion adapted to be received by the open portion of the channel-section member and a second elongate portion, attached to the first elongate portion, adapted to be received in that portion of the channel section member beneath the overhanging lip, and is characterised by an elongate slot extending partially through the insert between the first and second elongate portions, and at one end of which the first and second elongate portions are joined. Such an insert may be slid into a lipped, channel-section member and fills substantially the whole of the interior of the channel-section member. The channel-section member may then be set into concrete, and upon setting of the concrete the insert may be easily removed by slitting it along the or each elongate slot to remove that portion of the insert in the open portion of the channel-section member. The or each remaining portion of the insert positioned beneath the or each lip may then be easily pulled out. Preferably, the or each elongate slot separating the first and second portions extends to a point adjacent to the base of the insert. By way of example only, specific embodiments of the present invention will now be described, with reference to the accompanying drawings, in which;- Fig. 1 is a perspective view of a channel-section member fitted with a first embodiment of insert in accordance with the present invention; Fig. 2 is a cross-section of the member and insert of Fig. 1; Fig. 3 is a perspective view of the insert of Fig. 1; Fig. 4 is a perspective view showing how the channel-section member and insert are temporarily attached to shuttering before the application of concrete to form a wall; Fig. 5 is a perspective view, partly cut away, of part of a wall having the channel-section member of Fig. 1 set therein, together with other members of a framework connected to the member; and Fig. 6 is a perspective view of a second embodiment of insert in accordance with the present invention. Referring firstly to Figs. 1 and 2, an elongate channel-section member 10 comprises a flat planar base 12 and two parallel, opposed side walls 14, 16 extending substantially perpendicularly to the plane of the base 12, the edges formed by the conjunction of the base 12 and the side walls 14, 16 being rounded. The upper ends of the side walls 14, 16 are turned back upon themselves through 180° to form two, opposed, parallel, inwardly-directed longitudinal lips 18, 20, which extend along the whole of the channel-section member. The lips define an aperture opposite the base 12 of the member having a width d. At spaced intervals along the base 12, anchoring lugs 22 are pressed out so that they extend outwardly from the outer surface of the base 12. Each lug comprises a first portion 24 substantially perpendicular to the plane of the base 12 and an end portion 26 which lies substantially parallel to the plane of the base portion 12. The insert comprises a central, generally rectangular portion 28 which is flanked by two thinner, substantially parallel side portions 30, one portion being situated on either side of the block 28. The block 28 and the two side portions 30 are all integrally formed from the expanded polystyrene foam, and are all connected together, as can be seen from the Figures. The insert further comprises two elongate slots 32 running parallel to the longitudinal direction of the insert. The slots are approximately 1.5mm wide and extend to a point approximately 3mm from the base of the insert. The width of the central block 28 is narrower than the width d of the aperture between the lips 18,20 by a distance equal to the total of the slot widths, i.e. approximately 3mm narrower than the aperture. Also, the inner upper edge of the side portions 30 is cutaway to define a further recess 34, each of which is adapted to receive a respective one of the two lips 18, 20 of the channel-section member. In use, one or more inserts are slid longitudinally into the channel-section member, so that substantially the whole of the volume of the member is filled. It can be seen from Fig. 2 that when in position, substantially the whole of the volume of the channel-section member is filled with the expanded polystyrene foam insert. In particular, the edges of the lips 18, 20 of the elongate channel-section member abut the recesses 34 in the side portions of the insert, thereby protecting those edges. It can also be seen that the uppermost, projecting portions 36 of the side portions 30 fit snugly into that portion of the volume of the channel-section member between the lips 18, 20 and their respective side walls 14, 16. With the inserts in position in the channel-section member, the member is temporarily affixed in its position, by, for example, nailing the member with nails 38 to wooden shuttering 40 (Fig. 4) which is to hold concrete when poured. The concrete is then poured in, and sets to form a wall 42 (as seen in Fig. 5) as defined by the shape of the enclosing shuttering which is then removed. Thus, the channel-section member is set firmly into the concrete wall thus formed, and the lugs 26 provide a firm anchorage in the wall. Without the use of the insert, the concrete would flow into the channel-section member through the apertures in the base 12 of the member, and would set within the member, making it unsuitable for use. However, with the insert in accordance with the present invention, substantially the whole volume of the channel-section member is taken up by the insert, such that there is nowhere inside the channel-section member for the concrete to flow. Thus, the channel-section member, and in particular the lips 18, 20, does not become fouled by concrete. Once the concrete has set and the shuttering has been removed, it is necessary to remove the insert from within the channel-section member. This is done by inserting a sharp blade, for example a knife blade, into each of the slots 32 in turn, and running the blade along the slots in a direction parallel to the longitudinal axis of the insert. Such an action cuts through the small amount of foam which connects the central block 28 to the two flanking blocks 30, and the central block 28 may then be lifted away. Although expanded polystyrene foam is very difficult to cut, the very small thickness of foam which it is necessary to cut presents no problem in this respect. Once the central block 28 has been removed, the remaining side portions 30 may then be easily removed through the aperture between the lips 18, 20. Other members 44, 46 of the framework may then be inserted into, and secured in, the channel-section member 10, as seen in Fig. 5. A second embodiment of the insert is illustrated in Fig. 6 of the accompanying drawings. The insert is identical to that of the first embodiment, with a central, generally rectangular portion 28 which is flanged by two thiner, substantially parallel side portions 30, one portion being situated on either side of the block 28. As in the first embodiment, the block 28 and the two side portions 30 are integrally formed from expanded polystyrene foam, and are connected together. The same reference numerals as used in the first embodiment will be used to refer to corresponding features in the second embodiment. The only difference between the first and second embodiments is the provision of a self adhesive tape 50 which is stuck onto that face of the insert which, in use, is adjacent to the base of the channel section member. Secured onto the tape in between the tape and the insert are two parallel nylon cords 52 which are positioned on the tape such that when the tape is applied to the insert the cords are aligned with the respective slots 32 in the insert, i.e. adjacent those portions of the insert which join the central portion 28 to the side portions 30. In use, the inserts are slid longitudinally into the channel-section member as before. The channel-section member is then temporarily affixed as before, and the concrete is poured in and sets to form a wall 42. Once the concrete has set and the shuttering has been removed, instead of inserting a sharp blade into each of the slots 32 in turn, it is merely necessary to pull each of the cords 52, which cuts through the small amount of foam connecting the central block 28 to the two side portions 30, and the central block 28 may then be lifted away. Once the central block 28 has been removed, the remaining side portions 30 may then be easily removed through the aperture. The above embodiment has been described with reference to a nylon cord, but it should be appreciated that the nylon cord can be replaced with any elongate member, for example, a string. In order that the cords or other elongate members may be easily accessible once the concrete has set, it is advisable to leave a length of cord and/or tape at the end of each insert, such that the cord and/or tape can project beyond the insert and channel-section member. The invention is not restricted to the details of the foregoing embodiments. In particular, the width and/or depth of the insert may be varied, as long as the depth of the portion connecting the central block with the or each side portion is small enough to allow it to be cut by a blade and/or a tape or other elongate member. Also, although the embodiments have been described for use with a channel-section member having two elongate lips overhanging the base, the invention is equally applicable to a member having a single overhanging lip or more than two overhanging lips. Nor is the construction of the present invention restricted to polystyrene foam or even to foam at all. The insert may, for example comprise polyurethane foam or may comprise some other material such as unfoamed plastics. Any material which can easily be severed may be used.

Claims: 1. An elongate insert for insertion into an elongate, open, channel-section member (10) having at least one elongate lip (18, 20) overhanging its base (12), comprising a first elongate portion (28) adapted to be received by the open portion of the channel-section member and a second elongate portion (30), attached to the first elongate portion, adapted to be received in that portion of the channel section member beneath the overhanging lip (18, 20), characterised by an elongate slot (32) extending partially through the insert between the first and second elongate portions (28, 30), and at one end of which the first and second elongate portions are joined. 2. An insert as claimed in claim 1, wherein the or each elongate slot (32) extends to a location adjacent to the base of the insert. 3. An insert as claimed in claim 1 or claim 2, wherein the second elongate portion (30) is provided with a further recess (34) adapted to receive an elongate lip (18, 20) of the channel-section member (10). 4. An insert as claimed in any of claims 1 to 3, comprising two second elongate portions (30), attached to the first elongate portion (28), each adapted to be received in a portion of the channel section member beneath respective overhanging lips (18,20), and two elongate slots (32), each extending partially through the insert between the first elongate portion (28) and a respective one of the second elongate portions (30), and at one end of which the first elongate portion and the respective one of the second elongate portions are joined. 5. An insert as claimed in any of claims 1 to 4, wherein the total width (d) of the first portion (28) and the or each elongate slot (32) is substantially equal to the width of the open portion of the channel-section member (10) into which the insert is adapted to be placed. 6. An insert as claimed in any of claims 1 to 5, further comprising a cord, string or other flexible elongate member (52) located on the base of the insert and extending substantially parallel to an associated elongate slot (32). 7. An insert as claimed in claim 6, comprising a respective cord, string or other flexible elongate member (52) for each elongate slot (32) in the insert. 8. An insert as claimed in claim 6 or claim 7, wherein the or each cord, string or other elongate flexible member (52) is affixed to the insert. 9. An insert as claimed in claim 8, wherein the or each cord, string or other elongate flexible material (52) is secured by means of an adhesive tape (50). 10. An insert as claimed in claim 9, wherein the tape (50) is provided with a cord, string or other elongate flexible material (52) and is subsequently affixed to the insert. 11. An insert as claimed in any of claims 1 to 10, wherein the insert comprises plastics. 12. An insert as claimed in claim 11, wherein the insert comprises a foam material. 13. An insert as claimed in claim 11 or claim 12, wherein the insert comprises polystyrene foam.

Inventors: BUXTON, NEIL, "MALVERN", CRITCHLEY, GERALD
Applicants: VANTRUNK ENGINEERING LIMITED
Application year: 1989
Main classification: E04G15
IPC codes: E04B1, E04G15