GB2498524A

GB2498524A - Tunnel lining

Info

Publication number: GB2498524A
Application number: GB201200691A
Authority: GB
Inventors: George Henry Slade
Original assignee: M3 GROUP Ltd
Current assignee: M3 GROUP Ltd
Priority date: 2012-01-17
Filing date: 2012-01-17
Publication date: 2013-07-24
Anticipated expiration: 2032-01-17
Also published as: GB2498524B; GB201200691D0; WO2013108025A2; AU2012200492A1; WO2013108025A3

Abstract

A tunnel lining method in which shutter panels 10 are assembled to form shutter rings that are connected end to end in a tunnel to form a concrete shutter 1, with an annular space between the tunnel and the shutter . Strengthening rings inside the shutter rings may be expanded to bear against the shutter rings with a force in a radially outward direction. Liquid concrete is pumped into the annular space and allowed to at least partially set, to form a lining for the tunnel. The shutter rings are then disassembled. The pressure of the liquid concrete may be monitored as it progressively fills the annular space and the supply of concrete is ceased when the pressure reaches a predetermined threshold. An end shutter ring may be disassembled when the concrete is at least partially set, an inflatable bag is introduced to the location and the bag 4 is inflated to support the concrete as it continues to set and may be dragged progressively therough the tunnel. Also independently claimed is the presence of an access port 15 in a shutter through which the concrete may be pumped.

Description

TUNNEL LINING

The present invention relates to tunnel lining.

It is known to line tunnels with concrete to provide a smooth inner surface. This may apply both to new tunnels and the refurbishment of existing tunnels.

One known method of lining tunnels is to assemble fornnvork (shuttering inside an outer tunnel \vall to be lined, thereby to create an annular space between the inner formwork and outer ninnel wall, into which concrete is pumped. The formwork may be formed from a plurality of ring sections, which are secured together. When the concrete has set sufficiently, a set of form\vork ring sections may be disassembled from one end of the form\vork and re-assembled at the other end, ready to receive further concrete and extend the lining that is being formed.

Very often, a tunnel will he of generally circular cross-section.

However, tunnels may be of various other cross-sectional shapes. For ease of reference, outer tunnel walls and forrnwork as mentioned above will he described as being in the form of rings, it being understood that such rings could have any desired cross-sectional shape.

Preferred embodiments of the present invention aim to provide tunnel lining methods and apparatus that are generally improved.

According to one aspect of the present invention, there is provided a method of lining a tunnel, comprising the steps of assembling a plurality of shutter panels to form a plurality of shutter rings; assembling the shutter rings end to end in the tunnel to form a concrete shutter with an annular space between the tunnel and the shutter; pumping liquid concrete into the annular space; allowing the concrete to set to form said lining; and disassembling the shutter rings when the concrete is at least partially set.

Preferably, the method further comprises the steps of monitoring the pressure of the liquid concrete as it progressively fills the annular space and ceasing the supply of concrete when the pressure reaches a predetermined threshold.

Preferably, the pressure of the liquid concrete is monitored along a supply line to the shutter.

Preferably, the pressure of the liquid concrete is monitored on at least one of the shutter panels.

Preferably, the method further comprises the steps of disassembling an endmost one of the shutter rings when the concrete is at least partially set; introducing an inflatable bag to the location of the shutter ring that has been disassembled; and inflating the hag to support the concrete as it continues to set.

The inflatable bag may he draed progressively along the tunnel as the lining is formed and the shutter rings disassembled.

Preferably, the shutter panels of the shutter rings are held together circumferentially by bolts that engage captive nuts on the shutter panels.

Preferably, the shutter panels of the shutter rings are also held together circumferentially by locating pins that engage holes or slots formed on the shutter panels as an interference fit.

Preferably, the method further comprises the steps of engaging centring bolts with captive nuts on the shutter panels and tightening the centring bolts such that they protrude externally of the shutter to engage inner walls of the tunnel and therefore locate the shutter in a desired position with respect to the tunnel.

Preferably, said centring bolts have bolt heads that are engaged by a power tool to tighten the bolts.

Preferably, the method further comprises the steps of fitting strengthening rings inside the shutter rings and expanding the strengthening rings to bear against the shutter rings with a force in a radially outward direction.

Preferably, the method further comprises the step of applying floor panels to the lower part of the concrete shutter, to provide a floor along the concrete shutter.

Preferably, the method further comprises the step of providing rails along the floor panels and transport devices that run along the rails.

Preferably, the method further comprises the step of providing a foam material under said floor panels.

Preferably, the method further comprises the step of providing a track along the upper, inner part of the concrete shutter, for the transport of materials along the track.

Preferably, said track is a monorail.

Preferably, the method further comprises the step of providing the shutter panels with a gloss finish, ar least on their outer surfaces.

Preferably, said gloss finish is provided by a powder coating process.

A method according to any of the preceding aspects of the invention preferably further comprises the steps of disassembling an endmost one of die shutter rings when the concrete is at least partially set; and re-assembling the disassembled shutter ring at an opposite end of the concrete shutter, thereby to extend said annular space.

In another aspect, the invention provides apparatus for lining a tunnel, comprising a plurali of shutter panels assembled to form a plurality of shutter rings, which are assembled end to end in die tunnel ro form a concrete shutter with an annular space between the tunnel and the shutter; an access port in at least one of the shutter panels; and a pump arranged to pump liquid concrete through the access port into the annular space.

Such apparatus preferably further comprises means arranged to perform a merhod according t.o any of the preceding aspecrs of the invention.

For a better understanding of the invention, and to show how embodiments of die same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings, in which: Figure 1 is a perspective view of a shutter panel, showing its exterior surface; Figure 2 is a view of the shutter panel, showing its interior surface; Figure 3 is a perspective view of a plurality of shutter panels assembled together; Figure 4 is a perspective view of assembled shutter panels, reinforced by strengthernng rings; Figure 3 is a detailed view of an expansion fitting as used in the strengthening rings of Figure 4; Figure 6 is a perspective view of assembled shutter panels with a floor section, rail tracks and overhead rail; and Figure 7 is diagrammatic sectional view of a part-formed tunnel lining, partially supported by an inflatable bag.

In the figures, like references denote like or corresponding parts.

The shutter panel 10 sho\vn in Figures 1 and 2 is formed from steel, with a smooth outer surface 11 and an inner surface from which ribs 12, 13, 14 and 17 project inwardly. The ribs 12 are provided along the longitudinal sides of the panel 10. The ribs 13, 14 and 17 extend transversely of the panel 10. The rib 14 is located centrally of the panel 10 and is of greater width than the other transverse ribs 13, 17, to afford a bearing surface for a reinforcing ring, explained further below. The ribs 17 are at the longitudinal ends of the panel 10.

Preferably, the ribs 12, 13, 14, 17 are laser cut for accuracy, and welded to the rest of the panel 10.

The panel 10 is provided with a smooth gloss finish, at least on its outer surface 11, to facilitate a high quality finish of the concrete tunnel lining to he formed, and also to extend the life of the shutters. For example, the shutter panel 10 may he fmished with a white po\vder coat application to all surfaces.

A relatively large hole ISis fornied in the panel 10, to serve asn access port for feeding liquid concrete in use of the panel. Two smaller holes 16 are formed in the panel 10 and provided with captive nuts, with which large bolts engage to extend radially outwardly of the panel 10 in use, as explained further below.

Shutter panels 10 may be provided in different sizes and shapes, depending upon the shape of the tunnel to be lined. Not all panels need he provided with a large hole 15 for liquid concrete feed. The holes 16 with captive nuts may be provided in various different numbers and at various different locations on the panels.

In Figure 3, a plurality of shutter panels 10 are assembled together to form a series of ring sections that are connected together end-to-end, thereby to afford an elongate shutter 1 or formwork that is erected inside a tunnel to be lined. Figure 3 is a partial view of the forniwork, more extensive views of which are shown in Figures 4 and 6.

The shutter panels 10 are secured together circumferentially by locating pins 20 that cngagc as an interfercnce fit with corresponding holes and/or slots formed in the ribs 12 along the sides of the panels. Once the locating pins 20 are in position, thereby locating the shutter panels 10 in correct juxtaposition, bolts 21 are engaged with captive nuts 22 provided adjacent further holes and/or slots in thc ribs 12, and thc bolts 21 arc tightened firmly to secure the panels 10 firmly together. For example, the bolts 21 may be 16mm Dvwidag TM bolts, engaging corresponding nuts 22.

Further locating pins 23 engage as an interference fit with corresponding holes and/or slots 25 formed in the ribs 17 at the ends of the panels 10, to secure panels 10 together end-to-end. Once complete ring sections are assembled from shutter panels 10 and secured end-to-end, there is less tendency for the ring sections to move longitudinally than there is for the panels to move radially. Therefore, the locating pins 23 may be sufficient to secure the ring sections together end-t.o-end. Tjowever, bolts and captive nuts such as those 21, 22 along the side ribs 12 may be provided in a like manner on the end ribs 17, to fix the panels 10 more securely together.

Large bolts 24 engage with the captive nuts 16 on the shutter panels 10 and extend radially of the ring sections to engage with the inner surface of the tunnel to he lined. The bolts 24 serve to locate the formwork shutter centrally in the tunnel and pre-tension the shutter when tightened. For example, each bolt 24 may he made from 28mm Dy\vidag (RTM screw bar, to which a nut is welded at one end to form a head that can be driven by an air-or electric-powered ratchet gun.

Tn Figure 3, the visible panels 10 are of a somewhat different pattern to that of Figures 1 and 2, in that the holes with captive nuts 16 are provided adjacent side ribs 12 and there is no large feed hole 15. Typically, shutter panels of the pattern shown in Figures 1 and 2 flay he used at the top of the shutters -unused feed holes 15 being suitably closed off.

Preferably, holes 15, 16 in the shutter panels 10 and holes and/or slots in the ribs 12, 17 for locating pins 20, 23 and fixing bolts 21 are laser cut for accuracy.

As shown in Figure 4, internal reinforcing rings 30, e.g. of steel, may be introduced at intervals along the assembled formwork shutter 1. Each ring 30 comprises two side parts 31 that are joined by a centre part 32 located at the bottom of the shutter 1, such that the side parts 31 may pivot with respect to the centre part 32. At the top of the shutter 1, die two side parts 31 are joined by an expansion fitting 33 (e.g. a 27 mm Dywidag (RTM) expansion fitting) that allows the tops of the side parts 31 t.o he urged apart, thereby urging the reinfbrcing ring 30 against the shutter panels 10. Preferably, the reinforcing rings 30 bear against enlarged ribs 14 of the panels, as illustrated in Figure 2.

As shown in Figure 6, an assembled shutter I may incorporate floor panels 40 to facilitate worlung and access inside the shutter 1. Expanding foam may he used to fill voids between die floor panels and the shutter panels 10 below. A rail track 41 may be installed on the floor panels to take rail cars or shutter troffies. An overhead track monorail 42 may he provided, installed to a soffit plate of the shutter 1, to facilitate the movement of materials through die shutter I. The floor panels 40 may pass over flume pipes if present, and/or a live flow of\vater or other liquid may be channelled under the floor panels 40.

In Figure 6, strengthening ring side parts 31 can he seen laid along the shutter 1, prior to installation.

Figure 7 is a simplified schematic diagram, showing two shutter ring sections Ia and lb assembled end-to end inside an outer tunnel 2 to he lined. In practice, more than two shutter ring sections may be assembled end-to end.

Each shun-er ring section la and lb is assembled from shutter panels It) as descrihed above. Liquid concrete is supplied via a feed line 5 that is connected to a feed hole 15 in one of the shutter panels 10, located at the top of the ring section lb. The liquid concrete is supplied by a pump 6 under the control of a controller 7. A pressure sensor 8 is located in the feed line 5 at or adjacent the pump 6, t.o measure the pressure of liquid concrete in the line 5. Pressure sensors 9 are provided on the shutter panels 10 to measure the pressure of concrete on the shutter face.

Liquid concrete is pumped through the feed hole 15 to progressively fill the annular void between the shutter I and the tunnel 2. Pressure at the sensors 8 and 9 is continuously monitored and the pump is stopped when the controller 7 detects that sufficient concrete has been pumped int.o the void. By way of example only, initially the pressure at the sensor 8 is high, but once the liquid concrete starts to move, this may settle down to around 400psi. As the void fills up, the pressure in the line 5 increases and \vhen it reaches 2000 psi, this indicates that the void has been filled. The sensors 9 on the shutter panels 10 measure the pressure of the concrete on the shutter face. This starts off at 7ero and then builds up to lOOpsi when the void has been filled. As greater pressure is required to move the liquid concrete, the pressure at the sensor 8 near (or at) the pump 6 is generally higher than that at the sensors 9 on the shutter panels 10. Tt is to he appreciated that the pressure values given above are by way of example only, and can vary in dependence upon various conditions, such as the composition of the concrete, the thickness of the void, the length of the tunnel, the pumping distance, etc. -10 -In Figure 7, a tunnel lining 3 is in the course of being formed, with a section 3a in progress around the ring section lh, and a previously formed section 3b to the right of the ring section lb. A bag 4 has been inflated inside the lining section 3b, to support the lining section 3b as it cures. As successive sections of lining 3 are created, the right-most ring section (lb as shown in this example) is disassembled and re-assembled to the left of the left-most section (la as shown in this example). As the right-most section ring lb is disassembled and moved, the inflatable bag 4 is dragged up to replace it in position, to continue supporting the concrete whilst it sets. More than one bag 4 maybe provided in series, as required.

Methods and apparatus as illustrated and described above may facilitate the lining of a tunnel in an effective and efficient manner.

In this specification, the verb "comprise" has its normal dictionary meaning, to denote non-exclusive inclusion. That is, use of the word "comprise" (or any of its derivatives) to include one feature or more, does not exclude the possibility of also including further features.

All or any of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all or any of the steps of any method or process so disclosed, may he combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), maybe replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, -11 -unless expressly stated othenvise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the detnils of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of die features disclosed in this specification (including any accompanying claims, ahstracr and dra\vings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

<claim-text>-12 -CLAIMS1. A method of lining a tunnel, comprising the steps of assembling a plurality of shutter panels to form a plurality of shutter rings; assembling the shutter rings end to end in the tunnel to form a concrete shutter with an annular space between the tunnel and the shutter; pumping liquid concrete into the annular space; allowing the concrete to set to form said lining; and disassembling the shutter rings when the concrete is at least partially set.</claim-text> <claim-text>2. A method according to claim 1, further comprising the steps of monitoring the pressure of the liquid concrete as it progressively fills the annular space and ceasing the supply of concrete when the pressure reaches a predetermined threshold.</claim-text> <claim-text>3. A method according to claim 2, wherein the pressure of the liquid concrete is monitored along a supply line to the shutter.</claim-text> <claim-text>4. A method according to claim 2 or 3, wherein the pressure of the liquid concrete is monitored on at least one of the shutter panels.</claim-text> <claim-text>5. A method according t.o any of the preceding claims, further comprising the steps of disassembling an endmost one of the shutter rings when the concrete is at least partially set; introducing an inflatable bag to the location of the shutter ring that has been disassembled; and inflating the bag to support the concrete as it continues to set.</claim-text> <claim-text>6. A method according to claim 5, the inflatable bag is dragged progressively along the tunnel as the lining is formed and the shutter rings disassembled.</claim-text> <claim-text>-13 - 7. A method according to any of the preceding claims, wherein the shutter panels of the shutter rings arc held together circumferentially by bolts that engage captive nuts on the shutter panels.</claim-text> <claim-text>8. A method according to claim 7, wherein the shutter panels of the shutter rings are also held together circumferentially by locating pins that engage holes or slots formed on the shutter panels as an interference fit.</claim-text> <claim-text>9. A method according to any of the preceding claims, further comprising the steps of engaging centring bolts with captive nuts on the shutter panels and tightening the centring bolts such that they protrude externally of the shutter to engage nner walls of the tunnel and therefore locate the shutter in a desired position with respect to the tunnel.</claim-text> <claim-text>10. A method according to claim 9, wherein said centring bolts have bolt heads that are engaged by a power tool to tighten the bolts.</claim-text> <claim-text>11. A method according t.o any of the preceding claims, further comprising the steps of fitting strengthening rings inside the shutter rings and expanding the strengthening rings to bear ag-ainst the shutter rings with a force in a radially outward direction.</claim-text> <claim-text>12. A method according to any of the preceding claims, further comprising the step of applying floor panels to the lower part of the concrete shutter, to provide a floor along the cencrete shutter.</claim-text> <claim-text>13. A method according to claim 12, further comprising the step of providing rails along the floor panels and transport devices that run along the rails.</claim-text> <claim-text>-14 - 14. A method according to claim 12 or 13, further comprising the step of providing a foam material under said floor panels.</claim-text> <claim-text>15. A method according to any of the preceding claims, birther comprising the step of providing a track along the upper, inner part of the concrete shutter, for the transport of materials along the track.</claim-text> <claim-text>16. A method according to claim 15, wherein said track is a monorail.</claim-text> <claim-text>17. A method according t.o any of the preceding claims, further comprising the step of providing the shutter panels with a gloss finish, at least on their outer surfaces.</claim-text> <claim-text>18. A method according to claim 17, wherein said gloss finish is provided by a powder coating process.</claim-text> <claim-text>19. A method according to any of the preceding claims, further comprising the steps of disassembling an endmost one of the shutter rings when the concrete is at least partially set; and re-assembling the disassembled shutter ring at an opposite end of the concrete shutter, therehy to extend said annular space.</claim-text> <claim-text>20. Apparatus for lining a tunnel, comprising a plLLrality of shutter panels assembled t.o form a plurality of shutter rings, which are assembled end to end in the tunnel to form a concrete shutter with an annular space between the tunnel and the shutter; an access port in at least one of the shutter panels; and a pump arranged to pump liquid concrete through the access port into the annular space.</claim-text> <claim-text>21. Apparatus according to claim 20 and further comprising means arranged to perform a method according to any of claims 1 to 19.</claim-text> <claim-text>-15 - 22. A method of lining a tunnel, the method being substantially as hcrcinhcforc dcscrihcd with reference to the accompanying drawings.</claim-text> <claim-text>23. Apparatus for lining a tunnel, the apparatus being substantially as hereinbefore described with reference to the accompanying drawings.</claim-text>