GB2397632A

GB2397632A - Membrane securing means

Info

Publication number: GB2397632A
Application number: GB0301473A
Authority: GB
Inventors: Paul Bryan Callaghan
Original assignee: John Newton & Co Ltd
Current assignee: John Newton & Co Ltd
Priority date: 2003-01-22
Filing date: 2003-01-22
Publication date: 2004-07-28
Also published as: GB0301473D0

Abstract

The invention relates to securing means (2) for securing an impervious membrane (12) to the wall of a tunnel, the securing means (2) being provided by moulded plastic plug (4) adapted to be inserted, in use, in a pre-formed aperture (8) of the tunnel wall, a body portion (16) of the plug (4) being a force fit in said aperture (8). The plug (4) is provided with a threaded portion (18) wholly accommodated within the aperture (8) and arranged to be engaged by a threaded portion (24) of a fastener (6) of the securing means (2). The fastener (6) comprises a spool portion (22), which, in use in securing a membrane (12) to a tunnel wall, is located partially within said pre-formed aperture (8) and provides, externally of the tunnel wall, support for the membrane (12). The fastener (6) is provided with a through bore (28), which, when the securing means (2) is in use, is aligned with the blind bore (20) of the plug (4) to facilitate the attachment of support rails along said tunnel wall.

Description

IMPROVEMENTS IN MEMBRANE SECURING MEANS

This invention is concerned with improvements in or relating to means for securing a membrane to a substrate; particularly, this invention is concerned with improvements in securing means for attaching an impervious membrane to the wall of a tunnel.

Many diverse arrangements have been proposed hitherto for attaching impervious membranes to substrates, viz. the constructed walls of a tunnel and/or a rock face of a rough-hewn tunnel.

Whatever type of tunnel is to be lined, it has often been the practice to attach a lining or cladding by permanent securing means.

Thus, it is difficult to readily remove the lining or cladding to inspect the tunnel wall for subsequent deterioration that may be occasioned by the ingress of water from the natural water table surrounding the tunnel locale.

In addition to the incidence of water penetration into tunnels, the fabric of the tunnel wall requires periodic inspection; this is to ensure that the materials used for the components from which the tunnel is made are not deteriorating due to natural ageing.

It is an object of the present invention to provide an improved securing means that eliminates or at least mitigates some of the disadvantages of known securing means for the attachment of tunnel linings and the like..

Thus, the present invention conveniently provides a means for securing a membrane to a substrate, as hereinbefore defined, the securing means comprising a plug for insertion, in use, into a pre-formed aperture in said substrate, the plug having a threaded portion for engagement by a threaded fastener, characterized in that the threaded portion of the plug is wholly accommodated, in use, within the pre-formed aperture of the substrate.

Preferably, the fastener may comprise a spool portion, a leading end portion of which spool portion may be located partially within said preformed aperture of the substrate when in use.

Conveniently, the spool portion may comprise a trailing end portion, which may be located, in use, outside of said aperture for supporting a membrane to be secured to a substrate as aforesaid.

In a further preferred arrangement provided by the present invention, the fastener may comprise an internally threaded portion for engagement, when is use, with the threaded portion of the plug.

Conveniently, the fastener may also comprise a head of greater girth than that of the spool portion thereof, wherein, when the securing means is in use, a membrane, provided with a suitable hole, is attached to a substrate by the head of the fastener.

Preferably, the plug and the fastener may be made from plastic.

The present invention also conveniently provides means for attaching a membrane to a substrate, characterised in that the means for attaching comprises a plurality of securing means according to any one of the last six preceding paragraphs, which securing mean are arranged at spaced apart intervals along and across said membrane.

There now follows by way of example of the invention a detailed description, which is to be read with reference to the accompanying drawings in which: Figure 1 is a side view of a fastener of the invention; Figure 2 is a view in the direction of the arrow II in Figure 1; Figure 3 is a side view of a stud of the invention; Figure 4 is a view in the direction of the arrow IV in Figure 3; and, Figure 5 is a section view of the invention in use.

The securing means 2 of the present invention generally comprises a plug 4 and a fastener 6, the plug being adapted for insertion, in use, into a pre-formed aperture 8 of a substrate 10, the fastener 6 of the securing means 2, in combination with the plug 4, being used to attach a membrane 12 to the substrate 10, see Figure 5.

The plug 4, which is moulded from a plastic material, comprises a barbed portion 14 adapted to be a force-fit in the pre-formed aperture 8, the plug 4 further comprising a body portion 16 adjacent the barbed portion 14 and being of the same diameter as the barbed portion, see Figures 3 and 5; the body portion also being a force-fit in said aperture 8.

The plug 4 further comprises a threaded portion 18 to the left of the body portion 16 thereof, see Figures 3 and 5, which threaded portion 18 is wholly accommodated, in use, within the pre-formed aperture 8.

The plug 4 is provided with a blind bore 20 extending from a left hand end of the plug 4, see Figures 3 and 5, to allow for compression of the plug 4 as it is pressed into the pre-formed aperture 8. Also, as will be made apparent herein, the blind bore 20 facilitates the attachment of support rails, not shown, to the substrate 10.

The fastener 6 comprises a spool portion 22, which is the same diameter as the body portion 16 ofthe plug 4. The spool portion 22 is located, in use, partially within the pre-formed aperture 8 so that a leading end portion 22a thereof is in said aperture 8 while a trailing end portion 22b thereof is outside of said aperture 8.

The fastener 6 is provided with an internal screw thread 24, see Figures 1 and 5, whereby, in use, the fastener 6 may be threaded onto or off the threaded portion 18 of the plug 4 for a purpose to be described hereinafter.

The fastener 6 also comprises a hexagonal head 26 to facilitate threading the fastener onto the plug 4. In addition, the fastener 6 has a through bore 28, which, in use and in combination with the blind bore 20 of the plug 4, facilitates the attachment of support rails for services, not shown, in the membrane 12 and thus the substrate 10.

In use of the securing means 2, an operative inserts a plug 4 into a preformed aperture 8 in the substrate 10 of a tunnel wall, the plug 4 being inserted in the aperture 8 to a depth as shown in Figure 5.

The operative then locates a membrane 12 of impervious material 12 with a pre- formed hole 30 overlying the pre-formed aperture 8 and the plug 4 inserted therein.

The operative then screws a fastener 6 onto the plug 4 to thereby attach the membrane 12 to the substrate 10 ofthe tunnel wall, see Figure 5.

The impervious material may be any plastic and/or rubberised material suitable for use in lining a tunnel or the like.

It will be readily appreciated that the securing means 2 will be used to good effect if a plurality of means 2 are used at spaced intervals along and/or across the membrane to be attached to a tunnel wall.

It will be further appreciated that the membrane may be removed at any time simply by removing the fasteners 6 thereby allowing the substrate 10 to be inspected for deterioration due to the ingress of water.

Claims

1. A means for securing a membrane to a substrate as hereinbefore defined, the securing means comprising a plug for insertion, in use, into a preformed aperture in said substrate, the plug having a threaded portion for engagement by a threaded fastener, characterised in that the threaded portion of the plug is wholly accommodated, in use, within the pre-formed aperture of the substrate.

2. A securing means according to Claim 1, characterised in that the fastener comprises a spool portion, a leading end portion of which spool portion is located partially within said pre-formed aperture of the substrate when in use.

3. A securing means according to Claim 2, characterised in that the spool portion comprises a trailing end portion, which is located, in use, outside of said aperture for supporting a membrane to be secured to a substrate as aforesaid.

4. A securing means according to any one of Claims 1, 2 and 3, characterised in that the fastener comprises an internally threaded portion for engagement, when is use, with the screw threaded portion of the plug.

5. A securing means according to any one of Claims 2, 3 and 4, characterised in that the fastener comprises a head of greater girth of greater girth than the spool portion thereof, wherein, when the securing means is in use, a membrane, provided with a suitable hole, is secured to a substrate by the head of the fastener.

6. A securing means according to any one of the preceding Claims, characterised in that the plug is made from plastic.

7. A securing means according to any one of the preceding Claims, characterised in that the fastener is made from plastic.

8. Means for joining a membrane to a substrate, characterised in that the joining means comprises a plurality of securing means according to any one of Claims 1 to7.

9. Means for joining a membrane to a substrate according to Claim 8, characterized in that the securing means are arranged at spaced apart intervals along and across said membrane.