EP3631167A1

EP3631167A1 - A drainage system

Info

Publication number: EP3631167A1
Application number: EP18722088.4A
Authority: EP
Inventors: Kai SAARIKIVI; Harri VÄISTÖ
Original assignee: Norrapro Oy
Current assignee: Norrapro Oy
Priority date: 2017-05-31
Filing date: 2018-04-20
Publication date: 2020-04-08
Anticipated expiration: 2038-04-20
Also published as: EP3631167B1; WO2018220259A1; FI20175488A1; EP3631167C0; FI128880B

Abstract

A drainage system of a tunnel for underground construction to be arranged on an upward wall and/or a roof of the tunnel is provided. The drainage system comprises a draining pipe for leading the water away. The drainage system further comprises a frame, the draining pipe being connected to the frame with at least one fastener. The drainage system comprises at least one revision pipe which is arranged on transverse direction with respect to the draining pipeand the revision pipebeing connected to the draining pipe.

Description

A DRAINAGE SYSTEM

FIELD

The invention relates to a drainage system. In particular, the invention relates to a revision pipe for the drainage system of a tunnel for underground construction .

BACKGROUND

Underground construction has been popular research topic recently. There are several challenges relating to the development of the underground construction. One challenge is the water leakage that occurs in the roof or in the walls of the caverns, tunnels or rock caves. Currently vertical draining pipes are arranged on the tunnels for leading the water from the roofs or walls to horizontal draining pipes which are arranged on the bottom of the tunnel. The vertical draining pipes are usually covered with a layer of shotcrete. However, localization or recognition of the draining pipes is challenging due to the concrete layer. Thus, maintenance or repair of the draining pipes is not possible. Further, if the draining pipes are lost under the concrete layer, new draining pipes are needed to be assembled which results in high material and installation costs. Documents FI-680-U, JP-2013096071- A and WO-2009005438-A1 disclose some drainage systems for underground constructions. SUMMARY

The following presents a simplified summary of the disclosure in order to provide a basic understanding to the reader. This summary is not an extensive overview of the disclosure and it does not identify key or critical elements or delineate the scope of the specification. Its sole purpose is to present a selection of concepts disclosed herein in a simplified form as a prelude to the more detailed description that will be presented later.

According to one aspect, a drainage system of a tunnel for underground construction to be arranged on an upward wall and/or a roof of the tunnel is provided. The drainage system comprises a draining pipe which is arranged on the tunnel wall and/or roof for leading the water away. The drainage system comprises a frame, the draining pipe being connected to the frame, the frame comprising a back side and a front side, at least one fixing point on the back side of the frame for fixing the draining pipe to the frame with at least one fastener. The drainage system comprises at least one revision pipe which is arranged on transverse direction with respect to the draining pipe and the revision pipe being connected to the draining pipe.

According to an embodiment, the draining pipe which is arranged on the wall and/or roof of the tunnel, rock cave or cavern is typically covered with layer of concrete for attaching the draining pipe to the wall and/or roof effectively and to provide a fire-retardant layer. Finding the draining pipe can be challenging if the draining pipe clogs up. The drainage system enables recognition of the draining pipe under the concrete layer even if the draining pipe would be clogged up. The revision pipe can be used as an opening for filming the inner parts of the draining pipe and maintenance work can be done via the revision pipe.

BRIEF DESCRIPTION OF THE DRAWINGS

Many of the attendant features will be more readily appreciated as the same becomes better understood by reference to the following detailed description considered in connection with the accompanying drawings . In the drawings:

Figure 1 is a schematic and sectional back view of the drainage system,

Figure 2 shows a section I-I from Figure 1, Figure 3 is a schematic and sectional side view of the drainage system,

Figure 4 is a schematic and sectional front view of the drainage system,

Figure 5 is a schematic view of the drainage system as assembled into the wall of a tunnel,

Figure 6 is a schematic side view of the drainage system as assembled into the wall and roof of a tunnel,

Figure 7 is a schematic view of a branch tubing,

Figure 8 is a schematic view of a revision pipe arrangement,

Figure 9 is a schematic view of a connection between an inner end of the revision pipe and a branch tubing,

Figure 10 is a schematic view of disc-like flanges intended for supporting a revision pipe to a frame made of flexible material, and

Figure 11 is a schematic and sectional view of a supporting arrangement for a revision pipe.

Like reference numerals are used to designate like parts in the accompanying drawings.

DETAILED DESCRIPTION

Reference will now be made in detail to the following embodiments, examples of which are illustrated in the accompanying drawings. The detailed description provided below in connection with the appended drawings is intended as a description of the present examples and is not intended to represent the only forms in which the present example may be constructed or utilized. Referring to figures 1 to 4 a drainage system 13 comprises a draining pipe 9, a frame 1, the draining pipe 9 being connected to the frame 1 with at least one fastener 10 and at least one revision pipe 5 connected to drainage pipe 9. The frame 1 has a shape of a plate or strip. The frame comprises a back side 14 and a front side 15. The frame 1 is manufactured of a flexible material, for example from a polyethylene foam. The thickness of the frame 1 can be for example 10 mm. The width of the frame 1 can vary for example from 250 to 1000 mm. The length of the frame 1 can vary for example from 1 m to 50 m. Due to the flexibility, the frame 1 can be rolled up so that the frame 1 can be easily transported. The measures, which can vary, are presented in the application only as examples and should not be considered as limiting the scope of the claims. For example, thickness or width may have larger or smaller values than illustrated above or in the following description .

The frame 1 comprises support structures 3, 4 which are strips of a plate. The support structures 3, 4 are manufactured of a flexible material, for example from a polyethylene foam. The width of the support structure 3, 4 can vary for example from 50 to 70 mm. The thickness of the support structures 3, 4 can be for example 10 mm. The support structures 3, 4 are arranged on the longitudinal sides of the frame 1. The structures 3, 4 are attached to the frame 1 with an annealed wire 2 with technique known in the art. The size of the annealed wire 2 can vary for example from 2 to 5 mm.

A draining pipe 9 is attached to the frame 1 with at least one fastener 10 on at least one fixing point. The draining pipe 9 is attached preferably to the longitudinal center line of the frame 1. Usually there are several fasteners 10 in regular intervals. The draining pipe 9 is manufactured of a flexible plastic tube. The draining pipe 9 is manufactured of a water permeable material for leading the water into the draining pipe 9. The diameter of the draining pipe 9 can vary for example from 20 to 50 mm. The size of the draining pipe 9 can be selected according to the amount of water which is leaking. The fasteners 10 are manufactured of a flexible material, for example from a polyethylene foam.

After the draining pipe 9 has been arranged on the wall of the tunnel, there will be need to recognize the location of the draining pipe under a concrete layer and regularly inspect the inner parts of the draining pipe 9. Therefore, the drainage system 13 comprises at least one revision pipe 5 that can be opened for inspection. There can be several revision pipes 5 in regular intervals. The diameter of the revision pipe 5 can vary for example from 20 to 150 mm. The revision pipe 5 is arranged on the draining pipe 9 with a branch tubing 8. The branch tubing 8 is arranged around the draining pipe 9. Thus, the revision pipe 5 may be transverse to the draining pipe 9. The revision pipe 5 may be tilted in respect to the frame 1, for example the angle of tilt may vary between 5° and 10°. A bracket of the branch tubing 8 is fitted inside the revision pipe 5. The revision pipe 5 extends through the frame 1. The revision pipe 5 is attached to the frame 1 with one or more feedthrough flanges 6. The feedthrough flanges are fastened with screws with butterfly nuts 7 to the frame 1. One feedthrough flange 6 is arranged on the back side 14 of the frame 1 and other feedthrough flange 6 is arranged on the front side 15 of the frame 1. The feedthrough flanges 6 provide seal against water leaks.

The head of the revision pipe 5 is equipped with a bellows plug 11. The bellows plug 11 may provide an airtight structure for the revision pipe 5 and it may prevent heat transfer into the revision pipe 5. The bellows plug 11 improves the fire safety of the drainage system 13. Furthermore, the bellows plug 11 may improve the overall fire security of the tunnel.

According to an embodiment, the drainage system 13 can be assembled to the wall and/or roof of the tunnel as presented in figures 5 and 6. The drainage system 13 can extend from the roof of the tunnel to the bottom of the tunnel and the drainage system 13 may cover a whole profile of the tunnel. The whole profile of the tunnel comprises the roof and the walls of the tunnel. The tunnel walls may have different shapes, i.e. they may be for example vertical or inclined. The drainage system 13 is attached to the wall and/or roof of tunnel with shotcrete. The drainage system 13 may be arranged in a vertical direction along the wall of the tunnel or the drainage 13 system may be arranged on an inclined wall of the tunnel. In any case, the drainage system 13 is pressed against the wall and/or roof in a way that the frame 1 and the support structures 3, 4 follow the rock surface from which the water leaks out. The draining pipe 9 is arranged against the wall of the tunnel for leading the water into the draining pipe 9. A grating 12 is placed on top of the drainage system 13 and the drainage system 13 is covered with a layer of shotcrete. The longitudinal sides of the frame 1 can be sealed with polyurethane foam. When the drainage system 13 is assembled, the water leaking out from the surroundings is guided via the drainage system 13 to the bottom of the tunnel. Separate horizontal draining pipes (which are not presented in the figures) are assembled to the bottom of the tunnel and they can receive the water from the drainage system 13.

The revision pipe 5 protrudes outward from the front side of the frame 1. The revision pipe 5 may be arranged on transverse direction (in relation to the drainage system 13) . The revision pipe 5 may be arranged on horizontal direction and thus the revision pipe 5 may be perpendicular to the draining pipe 9 or to the drainage system 13. The head of the revision pipe 5 may extend to the upper level of the concrete layer or the revision pipe 5 may extend over the upper level of the concrete layer. The revision pipe 5 can be cut so that the head of the revision pipe is at the upper level of the concrete layer. The revision pipe 5 thus enables the recognition of the drainage system 13 and the draining pipe 9 from the concrete layer. Furthermore, inspection and maintenance work can be carried out via the revision pipe 5. The revision pipe 5 can be opened by removing the bellows plug 11 or the revision pipe 5 can be open all the time and a camera can be led in through the opening into the draining pipe 9 for inspection. Alternatively, maintenance work can be accomplished when the revision pipe 5 is opened.

Figure 2 further discloses that an inner end of the revision pipe 5 is provided with a recess 16 whereby it has two branches 17a, 17b. The tubing 8 is mounted between the two branches whereby the branches hold the tubing 8 in place. Further, distal ends 18 of the branches 17a, 17b of the revision pipe 5 may pass the tubing 8 and the draining pipe 9 and may thereby extend to rock surface against which the drainage system is supported. Thus, the inner end of the revision pipe 5 serves as a support surface.

Figure 9 discloses that the connection between the branch tubing 8 and the revision pipe 5 is loose. In other words, diameter Dl of the inner periphery of the revision pipe 5 is dimensioned to be significantly greater than outer diameter D2 of a transverse pipe fitting 19 of the T-piece or tubing 8, whereby the revision pipe 5 surrounds the transverse pipe fitting 19 with clearance. An advantage of this loose fitting is that mounting is facilitated, and further, it allows the diameter Dl of the revision pipe 5 to be dimensioned greater so that maintenance work is facilitated through a wider passage. Figure 9 further discloses that the T-piece or tubing 8 may comprise thickened end portions 20a, 20b at coupling branches 21a, 21b and outer diameter D3 of the revision pipe 5 may be dimensioned in accordance with distance between the two thickened portions 20a, 20b. When the branched inner end 5b of the revision pipe 5 is mounted in place, outer walls of the revision pipe 5 are supported against the thickened portions 20a, 20b. This way a kind of shape locking is formed between the revision pipe 5 and the branch tubing 8. The inner end 5b of the revision pipe 5 remains well in place when being inserted. The disclosed coupling is easy and quick to make, and further, no additional fastening means or tools are required.

Figure 8 discloses that the outer end 5a of the revision pipe 5 may be sealed gas-tightly by means of a bellows plug 11. The bellows plug 11 is provided with a top part 11a configured to be set against an outer end 5a of the revision or inspection pipe 5, and an opposite rear part lib configured to be inserted inside the top portion 5a of the revision pipe 5. Between the top part 11a and the rear part lib is at least one bellow 23 or sealing element. Further, the top part 11a and the rear part lib can be moved b towards each other by means of one or more tightening screws 24, which are shown in Figure 4. When the screws 24 are tightened, the bellows 23 or sealing elements expand radially and press against inner periphery of the revision pipe 5 and form thereby a gas-tight sealing for the plug 11. At least the top part 11a of plug 11 is made of metal material, such as steel, or other fire-resisting material. The tightening screw members 24 may be made of stainless steel, such as austenitic stainless steel, whereby they endure well in harsh circumstances and allow the bellows plug 11 to be opened after spending several years in corrosive environment. Regarding the fire safety the tightness of the plug 11 is in important role since it prevents fire gases entering inside the revision pipe 5 and further inside the drainage system.

Figure 7 further discloses that the branch tubing 8 having the T -shaped configuration comprises two coupling branches 21a, 21b and one transverse feed/revision branch or pipe fitting 19. The coupling branches 21a, 21b may be provided with retaining elements 22, such as sealing rings, which may form frictional fastening with the drainage tubes inserted inside the branches 21.

The branch tubing 8 is not mounted to the rock surface, but instead, only the frame 1 of the drainage system 13 is mounted to the rock surface. An advantage of this is that mounting of the piping is fast and simple.

As it is shown in the Figures, the revision pipe 5 is connected to one single vertical draining pipe 9. Then there exist only two alternative passage ways to enter through the revision pipe 9, either upwards or downwards. An advantage of this arrangement is that feeding of the inspection camera system and the flushing system inside the transverse draining pipe branches is facilitated .

The branch tubing 8 is shaped to include smooth angles from the branch 19 to branches 21a, 21b. Corner radius R of the branch tubing is at least 20 mm. When large enough corner radius R is used, then inspection and flushing instruments bend easily when inserted via the branch tubing to the drainage pipes.

According to an embodiment, the revision pipe is made of fire-resisting material. The revision pipe may be made of stainless steel, such as austenitic stainless steel material, whereby the revision pipe is not only fire-proof but also tolerates well corrosive circumstances.

According to an embodiment, the drainage system comprises only one vertically orientated drainage pipe without being connected to any crossing drainage pipes. The vertical drainage pipe is provided with a dedicated revision pipe assembly. Then the water may flow effectively downwards towards the bottom of the tunnel or rock cavity, and further, the inspection and cleaning instruments are easy to insert inside the draining tube system and may be easily moved upwards and downward effectively and without jamming, whereby operating range of the inserted instruments may be long.

According to an embodiment, the revision pipe is arranged at mounting height h so that it can be reached from the bottom of the tunnel or rock cavity without any aid devices. Then, no separate lifting devices or ladders are needed for executing the maintenance work, and further, safety of the maintenance work is also improved. The mounting height h of the revision pipe from the bottom of the tunnel may be 1000 2000 mm, preferably 1400 - 1800 mm, whereby the maintenance can be performed in good ergonomic working positions. The mounting height h is disclosed in Figure 6.

Figure 11 discloses that root of the revision pipe 5 is sealed by compressing the flexible material, such as polyethylene foam, of the frame 1 between the flanges 6a, 6b positioned on opposite sides of the frame 1 at the root of the revision pipe 5. The flanges 6a, 6b may be pressed F towards each other by means of one or more screw members 25. The material of the frame 1 may form a bulge 26 towards the revision pipe 5 inserted to the opening 27. The flanges 6a, 6b may be made of stainless steel so that they are sufficient to compress the material of the frame 1 and are also sufficiently rigid to provide proper support for the revision pipe 5. The flanges 6a, 6b may serve as a retaining plate for the revision pipe 5 when the shotcrete is sprayed on the drainage system 13. The flanges 6a, 6b and the material between them form a kind of sandwich structure, which is relatively rigid and forms liquid tight sealing at the inner portion of the pipe 5.

As it is disclosed in Figure 10 the flanges 6a, 6b may be disc-shaped pieces outer diameters D4 of which may be 250 - 350 mm, preferably 300 mm, and inner diameters D5 are dimensioned in accordance with an outer diameter D3 of the revision pipe 5. The flange 6 may be relatively thin, whereby it is light in weight and is easy to manufacture by utilization of typical sheet metal working techniques. The flanges 6a, 6b may comprise openings 28 allowing the mentioned screw fastening .

In one embodiment, the revision pipe is connected to the draining pipe with a branch tubing arranged around the draining pipe.

In one embodiment, the revision pipe protrudes outward from the front side of the frame.

In one embodiment, the revision pipe is covered by a bellows plug.

In one embodiment, the transverse direction comprises horizontal direction.

In one embodiment, the upward direction comprises vertical direction. In one embodiment, the draining pipe is arranged on vertical direction on the tunnel wall.

In one embodiment, at least one revision pipe is arranged on horizontal direction.

In one embodiment, at least one revision pipe is arranged perpendicular to the draining pipe.

In one embodiment, the draining pipe is arranged upright on the tunnel wall for leading the water away.

It will be understood that the benefits and advantages described above may relate to one embodiment or may relate to several embodiments. The embodiments are not limited to those that solve any or all of the stated problems or those that have any or all of the stated benefits and advantages.

It will be understood that the above description is given by way of example only and that various modifications may be made by those skilled in the art. The above specification, examples and data provide a complete description of the structure and use of exemplary embodiments. Although various embodiments have been described above with a certain degree of particularity, or with reference to one or more individual embodiments, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this specification .

Claims

1. A drainage system (13) of a tunnel for underground construction to be arranged on an upward wall and/or a roof of the tunnel wherein the drainage system (13) comprises:

a draining pipe (9) which is arranged on the tunnel wall and/or roof for leading the water away;

a frame (1), the draining pipe (9) being connected to the frame (1), the frame (1) comprising a back side (14) and a front side (15); and

at least one fixing point on the back side (14) of the frame (1) for fixing the draining pipe (9) to the frame (1) with at least one fastener (10);

characterized in that

the drainage system (13) further comprises at least one revision pipe (5) which is arranged on transverse direction with respect to the draining pipe (9) and the revision pipe (5) being connected to the draining pipe (9) ; and

wherein the revision pipe (5) is covered by a bellows plug (11) .

2. The drainage system (13) according to claim 1, wherein

the revision pipe (5) is connected to the draining pipe (9) with a branch tubing (8) arranged around the draining pipe (9) .

3. The drainage system (13) according to claim 1 or 2, wherein

the revision pipe (5) protrudes outward from the front side (15) of the frame (1) .

4. The drainage system (13) according to any one of the preceding claims 1 - 3, wherein

the revision pipe (5) and the bellows plug (11) and made of fire-resisting material.

5. The drainage system (13) according to any one of the preceding claims 1 - 4, wherein

the revision pipe (5) is tilted (a) with respect to outer surface (14) of the frame (1) .

6. The drainage system (13) according to any one of the preceding claims 1 - 5, wherein

at an inner end portion (5b) of the revision pipe (5) are two feedthrough flanges (6a, 6b) arranged on opposite sides of the frame (1), and

the feedthrough flanges (6) are configured to compress the frame (1) between them and to seal the inner end portion (5b) of the revision pipe (5) to the frame ( 1 ) .

7. The drainage system (13) according to any one of the preceding claims 1 - 6, wherein

an inner end (5b) of the revision pipe (5) comprises a recess (16) for receiving the branch tubing (8) .

8. The drainage system (13) according to claim 7, wherein

an inner end portion (5b) of the revision pipe

(5) comprises two branches (17a, 17b) between which is the mentioned recess (16); and

distal ends of the branches (17a, 17b) are configured to serve as support surfaces supportable against rock surface.

9. The drainage system (13) according to any one of the preceding claims 1 - 8, wherein

an inner end portion (5a) of the revision pipe (5) is connected to a transverse pipe fitting (19) of the branch tubing (8) with a clearance fitting.