GB2325946A

GB2325946A - Sealing tunnel linings

Info

Publication number: GB2325946A
Application number: GB9711796A
Authority: GB
Inventors: Joern Reite
Original assignee: OERSTA STAALINDUSTRI
Current assignee: OERSTA STAALINDUSTRI
Priority date: 1996-04-11
Filing date: 1997-06-07
Publication date: 1998-12-09
Also published as: FI111184B; NO961445L; GB9711796D0; NO301786B1; NO961445D0; SE508208C2; FI971450A; SE9701317L; SE9701317D0; FI971450A0

Abstract

A tunnel lining consists of sheets of material 11, such as foam 11A with a fireproof layer 11 B of glass reinforced plastic, which are arranged with abutting joints and which are supported by rock bolts 13 anchored in holes in the rock of a tunnel ceiling and walls. The sheets of material 11 are supported at each circumferentially extending joint by exterior support elements 12A,12B which are connected to the series of rock bolts 13 by clamps 14 and by an interior support element comprised of two parallel bars 26 which are carried by webs 28 mounted on the rock bolts 13. Each joint is sealed by a sealing ribbon 19 extending along the length of each joint which is pressed against grooves 23 at the edges of sheets 11 by the exterior support elements 12A,12B. The strip 19 is also sealed to the rock bolts by washers 20 and sealing rings 21. The inside of each joint is covered by a strip 24.

Description

This invention relates to a device for the attaching and sealing of tunnel lining, as stated in the introductory part of claim 1.

Background For covering the inner surface of tunnels, corrugated metal sheets have been attached to the tunnel walls and ceiling and have been lined with insulation material or foam elements have been mounted and lined with injected concrete for improving fire safety. These methods are expensive and the joints have not been completely sealed.

Recently foam based sheets for mounting in tunnels as self carrying lining have been developed.

Object The main object of the invention is to provide a device for the attaching and sealing of tunnel lining, the use of which avoids overlap of the foam sheet joints and wherein, additionally, a fire proof material may be provided. It is a particular object to provide a device which permanently seals joints between foam sheets, in the vertical as well as in the horizontal direction, and when the gap between sheet edges is 5-10 cm.

It is a particular object to provide a device for attaching such a tunnel lining in an easy and labour saving manner.

The invention Such a device is described in claim 1. With such a device it is possible to mount the foam sheet lining of tunnels in an easy way, providing tight joints which will withstand the strain of temperature changes, air pressure and aging. The foam sheets may be protected with a further lining or with injected concrete.

Further features of the invention are stated in the subclaims.

Example The invention will be described further with reference to the accompanying drawings, in which: Fig. 1 shows a perspective view of a section of a tunnel, Fig. 2 shows a section through a vertical joint close to an attachment bolt, while Fig. 3 shows an interior part of the joint.

In Fig. 1 is shown a tunnel provided with a lining 11 of foam sheets, e.g. sheets of PEfoam 1 A with an interior compact layer l lB (Fig. 2) to provide resistance against fire, mechanical and climatic attacks and which rejects contamination. The cover layer l lB may be a composite, e.g. fiber glass reinforced plastic, which is made more fire resistant through the fiber glass.

The lining 11 is attached to a carrier consisting of a series of extended attachment elements, which in the following are in the form at denominated attachment strings 12 which extend transversely across the tunnel walls attached by rock bolts 13 anchored in the rock. The attachment strings 12 consist in this example of two steel bars 1 2A and 1 2B which are joined with a series of welded webs 12C of strip steel.

Fig. 2 shows an exposed rock bolt 13 of cam steel with a threaded end 1 3A.

On the threaded end 13A a clamp 14 for an attachment string 12 is secured. The clamp 14, which is shown in more detail in Fig. 3, has a cross bar 14A with a groove 14B and 14C at each end for accomodating the bars 12A and 12B of the attachment string 12. The clamp 14 is pressed of sheet steel. The grooves 14B and 14C in the example are C-shaped, to allow for an introduction and firm grip of the bars 12A and 12B by the knock of a hammer or similar. If this method of attachment is inconvenient, e.g. due to large variations in the dimensions, the clamps can be slidably attached to the bars 12A and 12B with its ends bent around the bars.

A tunnel is generally arch-shaped and so the lining sheets will then have different widths In the inner and the outer curve. In the inner curve the lining sheets may abut around the rock bolt 13, while at the outer curve a slit 17 of up to 100 mm may excist. To prevent leakage at the joints with varying width of the slit 17, a sealing band 19 of a flexible plastic material is covers the entire joint. The sealing band 19 is introduced onto the rock bolts 13.

To prevent water from entering the bolt holes, washers 20 and sealing rings 21 are provided on both sides of the sealing band. The washers are tightened by a nut 22. The sealing band 19 is pressed into grooves 23 cut into the exterior side of the lining sheets 11 by the attachment string 12 due to the pressure clamping force which will be described in the following. The grooves 23 in the lining sheets 11 are dimensioned to cover practical variations in the width of the slits 17 due to curvature of the tunnel. On the interior side of the lining sheets 11 a cover plate 24 is arranged on the rock bolts 13 for covering the slit between the lining sheets and make it resistant to fire. The cover plates 24 are pressed against the lining sheets by an inner attachment string 26 with a strip steel clamp 28 and a nut 27.

At the horizontal joints between the lining sheets, a longitudinal sealing band or membrane, a sealing band in the joint, or a groove-tongue-connection can be used to maintain the seal.

The tunnel lining and its attachment can be modified in various ways relative to the example. The exterior attachment string 12 may be replaced by a profile element, e.g.

perforated aluminium. The interior attachment string 26 may be partly or completely integrated with the cover plate 24.

Claims

Claims:

1. A device for the attaching and sealing of tunnel lining, in which a sheet material (1 1) is attached with abutting joints by suspension in rock bolts (11) anchored in holes on the rock of a tunnel ceiling and walls, said sheet material engaging an exterior support element (12A, 12B) which is connected to a series of rock bolts which are anchored in the rock, and wherein said sheet material (1 1) is supported at each crosswise extending joint (17) by an interior support element (26), being carried by webs (28) at the rock bolts (13), characterized in - that the exterior, rock facing support element comprises an extended supporting means (12A, 12B) on each side of the joint (17), wherein the exterior support means is fastened with transverse webs (14) at each rock bolt (13), and - that a sealing element (19) extending along the joints is arranged between the sheet material (11) and at least the exterior supporting means (12A, 12B).

2. The device according to claim 1, characterized in that the exterior support means is provided by at least two steel bars (12A, 12B) which are maintained parallel by spacers (12C).

3. The device according to claim 2, characterized in that the two steel bars (12A, 12B) are connected to the rock bolts (13) by a series of distributed cross members (14) which are provided with grooves (14B, 14C) at the ends for accomodating the two steel bars (12A, 12B) or which are slidably attached to the exterior support means (12A, 12B).

4. The device according to claim 3, characterized in that the grooves (14B, 14C) in the cross members are C-shaped.

5. The device according to anyone of the claims 1-5, characterized in that the lining sheet material (1 1) on the exterior side is provided with grooves (23) along the side edges for engagement of the exterior support means (12A, 12B).

6. The device according to claim 6, characterized in that the grooves (23) have a substantially larger width than the extenor support means (12A, 12B).

7. A device for the attaching and sealing of tunnel lining substantially as herein described with reference to and as shown in the accompanying drawings.

Amendments to the claims have been filed as follows 1. A device for the attaching and sealing of lining sheets in tunnels, in which the sheets (11) are attached with abutting joints by suspension in rock bolts (13) anchored in holes on the rock of a tunnel ceiling and walls, said sheets engaging an exterior support element (12A,12B) which is connected to a series of rock bolts which are anchored in the rock, and wherein said sheets (11) are supported at each crosswise extending joint (17) by an interior support element (26), being carried by webs (28) at the rock bolts (13), said webs crossing the sheet joints (17), characterised in that: the exterior support element comprises an extended supporting means (12A,12B) on each side of the joint (17), wherein the exterior support means is fastened with transverse webs (14) at each rock bolt (13), and a sealing element (19) extending along the joints is arranged between the sheets (11) and at least the exterior supporting means (12A, 12B).

2. The device according to claim 1, characterised in that the exterior support means (12) is provided by at least two steel bars (12A,12B) which are maintained parallel by a series of spacers (12C).

3. The device according to claim 2, characterised in that the webs (14) are provided with grooves (14B,14C) at the ends for accommodating the steel bars (12A,12B) or which are slidably attached to the steel bars (12A,12B).

4. The device according to claim 3, characterised in that the webs (14) comprise a U-section (14A) with C-shaped grooves (14B,14C) in the legs at each end.

5. The device according to any one of claims 1 to 4, characterised in that the sheets (11) on the exterior side are provided with grooves (23) along the side edges for engagement of the exterior support means (12A, 12B).

6. The device according to claim 5, characterised in that the grooves (23) have a substantially larger width than the exterior support means (12A, 12B).