EP1820934A1

EP1820934A1 - Method and system for forming a tunnel beneath a travelway

Info

Publication number: EP1820934A1
Application number: EP06394005A
Authority: EP
Inventors: Alvise Petrucco
Original assignee: Aix Research Ltd
Current assignee: Aix Research Ltd
Priority date: 2006-02-17
Filing date: 2006-02-17
Publication date: 2007-08-22

Abstract

A system forming a tunnel beneath a railway (1) comprises a tunnel member (3) a platform member (2) eight support members (4), a slide member (5) for the tunnel member (3), and two slide members (6) for the platform member (2). In use, the tunnel member (3) is constructed in-situ adjacent to one side of the railway (1) resting upon the tunnel slide member (5), and the platform member (2) is constructed in-situ adjacent to the opposite side of the railway (1) resting upon the pair of platform slide members (6). A section of the railway (1) is then removed and part of the ground that was beneath the removed section of the railway (1) is excavated. The platform member (2) is pushed along the platform slide members (6) until the platform member (2) is resting upon the eight support members (4), and the removed section of the railway (1) is then replaced. The ground beneath the railway (1) and the platform member (2) is then excavated, and the tunnel member (3) is pushed along the tunnel slide member (5) until the tunnel member (3) is under the railway (1). The tunnel slide member (5) and the platform slide members (6) are then removed. In this manner the tunnel is formed beneath the railway (1).

Description

Introduction

This invention relates to a system for forming a tunnel beneath a travelway, and to a method of forming the tunnel beneath the travelway.
It is known to form a tunnel beneath a railway by extending a series of beams under the railway and then moving a box tunnel under the railway. However to ensure that the railway is maintained in a fixed position during movement of the box tunnel under the railway, this approach requires a relatively complex clamping arrangement. This approach may result in a time-consuming and labour-intensive procedure.
This invention is aimed at providing an improved system for forming a tunnel beneath a travelway, and an improved method of forming the tunnel beneath the travelway.

Statements of Invention

According to the invention there is provided a method of forming a tunnel beneath a travelway, the method comprising the steps of:-

providing a platform member and a tunnel member, the platform member having a width greater than or substantially equal to the tunnel member;
locating the platform member in a location beneath the travelway to maintain the travelway in a substantially stable position; and
moving the tunnel member under the travelway to form the tunnel.

The platform member ensures that the travelway is maintained in a substantially stable and/or fixed position as the tunnel member is moved under the travelway. Because of the width of the platform member, the travelway is supported both in the transverse direction and in the longitudinal direction. A complex clamping arrangement is therefore not required with the invention in suit. It is possible to form a tunnel beneath a travelway in a relatively fast manner with a minimum of labour required using the invention in suit. Disruption to traffic passing along the travelway, for example rail traffic passing along a railway, may therefore be minimised.
When the platform member is wider than the tunnel member, this enables the platform member to be supported on either side of the tunnel member, as the tunnel member is being moved under the travelway. By supporting the platform member in the location beneath the travelway, this ensures that the platform member maintains the travelway in a substantially stable and/or fixed position even when ground beneath the travelway is being excavated for movement of the tunnel member under the travelway.
In one embodiment of the invention the method comprises the step of supporting the platform member in the location beneath the travelway. Preferably the method comprises the step of providing one or more support members to at least partially support the platform member in the location beneath the travelway. Ideally the platform member is at least partially supported by resting upon the support member. The support member may be provided to a side of the travelway. By providing the support member to the side of the travelway, this enables the support member to be constructed without affecting the travelway or disrupting traffic along the travelway. Most preferably one or more support members are provided to a first side of the tunnel member. Most preferably one or more support members are provided to a second side of the tunnel member. By providing the support member to the side of the tunnel member, this enables the platform member to be supported while the tunnel member is moved under the travelway. The support member may be constructed in-situ. In one case the support member comprises a concrete pier.
In another embodiment the platform member is at least partially supported in the location beneath the travelway by the tunnel member. Preferably the platform member is at least partially supported by resting upon the tunnel member.
The tunnel member may be constructed at a location adjacent to the travelway. The tunnel member may be constructed at a location remote from the travelway. The platform member may be constructed at a location adjacent to the travelway. The platform member may be constructed at a location remote from the travelway.
In another case the method comprises the step of excavating at least part of the ground beneath the travelway. Part of the ground beneath the travelway may be excavated before locating the platform member in the location beneath the travelway. Part of the ground beneath the travelway may be excavated before moving the tunnel member under the travelway.
In a preferred embodiment the platform member is located in the location beneath the travelway by moving the platform member into the location beneath the travelway. The platform member and the tunnel member may be moved from the same side of the travelway. The platform member and the tunnel member may be moved from opposite sides of the travelway.
In one embodiment the method comprises the step of removing at least part of the travelway before locating the platform member. Preferably the method comprises the step of replacing at least part of the travelway. At least part of the travelway may be replaced after locating the platform member. At least part of the travelway may be mounted to the platform member. In one case the method comprises the step of easing movement of the platform member and/or of the tunnel member. Preferably the method comprises the step of providing one or more slide members to ease movement of the platform member and/or of the tunnel member. The slide member may ease movement of the platform member and/or of the tunnel member by resting the platform member and/or the tunnel member upon the slide member. Ideally the slide member is constructed in-situ. Most preferally the method comprises the step of removing the slide member after moving the platform member and/or the tunnel member.
The tunnel member may comprise an open-topped member. The tunnel member may be substantially 'U'-shaped in cross-section. An end of the tunnel member may slope forwardly. Preferably the leading end of the tunnel member slopes forwardly.
The platform member may comprise a slab member.
The travelway may comprise a railway. The travelway may comprise a roadway. The travelway may comprise a pathway. The travelway may comprise a waterway.
In another aspect the invention provides a system for forming a tunnel beneath a travelway, the system comprising:-

a platform member locatable in a location beneath a travelway to maintain the travelway in a substantially stable position; and
a tunnel member movable under the travelway to form a tunnel;
the platform member having a width greater than or substantially equal to the tunnel member.

In one embodiment the system comprises one or more support members to at least partially support the platform member in a location beneath a travelway. Preferably the platform member is restable upon the support member. Ideally the support member comprises a concrete pier.
In another case the tunnel member is configured to at least partially support the platform member in a location beneath a travelway. The platform member may be restable upon the tunnel member.
In another embodiment the platform member is movable into a location beneath a travelway. At least part of a travelway may be mounted to the platform member.
The system may comprise one or more slide members to ease movement of the platform member and/or of the tunnel member. Preferably the platform member and/or the tunnel member is restable upon the slide member. The tunnel member may comprise an open-topped member. The tunnel member may be substantially 'U'-shaped in cross-section. An end of the tunnel member may slope forwardly. Preferably the leading end of the tunnel member slopes forwardly.
The platform member may comprise a slab member.

Brief Description of the Drawings

The invention will be more clearly understood from the following description of an embodiment thereof, given by way of example only, with reference to the accompanying drawings, in which:-

Fig. 1 is a perspective view of a travelway;
Fig. 2 is a plan view of the travelway of Fig. 1;
Fig. 3 is a view along line III-III in Fig. 2;
Figs. 4 and 5 are views similar to Figs. 2 and 3 of the travelway of Fig. 1, and support members and slide members of a system according to the invention for forming a tunnel beneath the travelway;
Figs. 7 and 8 are views similar to Figs. 2 and 3 of the travelway of Fig. 1, the support members and slide members of Figs. 4 and 5, and a platform member and a tunnel member of the system according to the invention;
Fig. 9 is a perspective view after removal of part of the travelway;
Figs. 10 and 11 are views similar to Figs. 7 and 8 after removal of part of the travelway;
Figs. 12 to 14 are views similar to Figs. 9 to 11 after location of the platform member in a location beneath the travelway;
Figs. 15 and 16 are views similar to Figs. 7 and 8 during movement of the tunnel member under the travelway;
Fig. 17 is a view along line XVII - XVII in Fig. 15;
Fig. 18 is a view similar to Fig. 9 after movement of the tunnel member under the travelway; and
Figs. 19 and 20 are views similar to Figs. 2 and 3 of the travelway of Fig. 1, and the platform member and the tunnel member of Figs. 7 and 8, after movement of the tunnel member under the travelway.

Detailed Description

Referring to the drawings, there is illustrated a system according to the invention for forming a tunnel beneath a travelway, such as a railway 1. The profile 9 of the tunnel underway which is to be built is illustrated in Fig. 2. The system comprises a tunnel member 3, a platform member 2 which is separate from the tunnel member 3, eight support members 4, a slide member 5 for the tunnel member 3, and two slide members 6 for the platform member 2.
The tunnel member 3 comprises an open-topped member having an 'U'-shaped cross-section, as illustrated in Figs. 7 and 8. Each end of the tunnel member 3 is open also, and the leading end 16 of the tunnel member 3 slopes forwardly (Fig. 8). The tunnel member 3 may be moved under the railway 1 by pushing the tunnel member 3 using hydraulic jacks 8 to form the tunnel beneath the railway 1.
The platform member 2 is provided in this case in the form of a slab member. As illustrated in Fig. 17, the platform member 2 is wider, in this case, than the tunnel member 3. The platform member 2 may be located in a location beneath the railway 1 to maintain the railway 1 in a substantially stable and/or fixed position, as the tunnel member 3 is moved under the railway 1 (Figs. 15 and 16). In particular the platform member 2 may be moved into the location beneath the railway 1 by pushing the platform member 2 using hydraulic jacks 7 (Figs. 7 and 8).
Each support member 4 is provided in the form of a concrete pier. Two pairs of support members 4 are provided on each side of the railway 1 (Fig. 4) with one pair of support members 4 provided on each side of the tunnel member 3 (Fig. 4). As illustrated in Figs. 13 and 14, when the platform member 2 is located in the location beneath the railway 1, the platform member 2 rests upon the support members 4. In this manner the support members 4 at least partially support the platform member 2 in the location beneath the railway 1.
The tunnel slide member 5 is provided in the form of a concrete floor (Figs. 4 and 5), upon which the tunnel member 3 may rest. The tunnel slide member 5 eases movement of the tunnel member 3 towards the railway 1 (Figs. 15 and 16) and under the railway 1. A fixed pushing wall 10 or push beam is provided at one end of the concrete floor 5 for the concrete sliding box tunnel 3.
Each platform slide member 6 is provided in the form of a narrow concrete strip (Figs. 4 and 5). Each platform slide member may be provided in the form of a foundation beam. In one example, the platform slide member 6 may have a length of approximately 1m and a thickness/depth of approximately 50cm.The platform member 2 may rest upon the pair of platform slide members 6. The platform slide members 6 ease movement of the platform member 2 into the location beneath the railway 1. A pushing wall 1 1 or push beam is provided at one end of each of the concrete floors 6 for the concrete sliding slab 2.
In use, the tunnel slide member 5 is constructed in-situ adjacent to one side of the railway 1, and the platform slide members 6 are constructed in-situ adjacent to the opposite side of the railway 1 (Figs. 4 and 5).
Two pairs of support members 4 are constructed in-situ adjacent to one side of the railway 1 with one pair of support members 4 to each side of the tunnel slide member 5 (Figs. 4 and 5). Similarly two pairs of support members 4 are constructed in-situ adjacent to the opposite side of the railway 1 with one pair of support members 4 to each side of the tunnel slide member 5 (Figs. 4 and 5). As illustrated in Figs. 4 and 17, each platform slide member 6 is aligned with a pair of support members 4 on one side of the railway 1 and with a pair of support members 4 on the opposite side of the railway 1.
The tunnel member 3 is constructed in-situ adjacent to one side of the railway 1 resting upon the tunnel slide member 5, and the platform member 2 is constructed in-situ adjacent to the opposite side of the railway 1 resting upon the pair of platform slide members 6 (Figs. 7 and 8). A section of the railway 1 is then removed and part of the ground, which is also known as the ballast, that was beneath the removed section of the railway 1 is excavated (Figs. 9 to 11). The platform member 2 is pushed along the platform slide members 6 using the hydraulic jacks 7 until the platform member 2 is resting upon the eight support members 4, and the removed section of the railway 1 is then replaced. The platform member 2 is thus located in the location beneath the railway 1 supported by the eight support members 4 (Figs. 12 to 14).
Instead of replacing the removed section of the railway 1, a new section of railway 1 may be mounted to the platform member 2 before pushing the platform member 2 into the desired location. In this manner the new section of railway 1 mounted to the platform member 2 replaces the removed section of the railway 1. In particular, the new section of railway 1 may be incorporated on the slab 2 before moving the slab 2. Therefore when the slab 2 is in position, the new section of railway 1 is already in the required position.
The ground or ballast beneath the railway 1 and the platform member 2 is then excavated, and the tunnel member 3 is pushed along the tunnel slide member 5 using the hydraulic jacks 8 (Figs. 15 to 17) until the tunnel member 3 is under the railway 1. The tunnel slide member 5 and the platform slide members 6 are then removed (Figs. 18 to 20). In this manner the tunnel is formed beneath the railway 1.
When the tunnel member 3 is in its final position beneath the railway 1, the platform member 2 may rest upon the two sidewalls of the tunnel member 3. In this manner the sidewalls of the tunnel member 3 may at least partially support the platform member 2. It will be appreciated that the platform member 2 may be supported in the location beneath the railway 1 by the pile support members 4, or by the sidewalls of the tunnel member 3, or by a combination of the support members 4 and the sidewalls of the tunnel member 3.
When the tunnel member 3 is in its final position beneath the railway 1, the platform member 2 acts as a top wall or as a roof, or as a top slab for the tunnel with the tunnel member 3 acting as the base and two side walls of the tunnel (Fig. 17).
In further detail, Figs. 2 and 3 illustrate the site starting condition with the profile of the underway or highway to be built. Figs. 4 and 5 illustrate building up of the concrete floor 5 for the sliding box tunnel 3. Figs. 7 and 8 illustrate construction of the box tunnel 3 and the concrete sliding slab 2. Figs. 10 and 11 illustrate temporary railway interruption and pushing of the slab 2. Figs. 13 and 14 illustrate the slab 2 pushed to its final position and fastening to the piers 4, and the railway 1 restored. Figs. 15 and 16 illustrate sliding of the box tunnel 3 and digging of the tunnel. Figs. 19 and 20 illustrate the box 3 pushed to its final position, and demolition of the box sliding structure 5 and progress of the underway construction.
This invention provides a method for tunnel construction, for example tunnels under railways or roads.
In the method of the invention, the tunnel box 3 is built alongside the railway track 1 with the top slab 2 larger, and separate from the box 3. The top slab 2 is supported by the tunnel walls and the two piles 4 positioned adjacent to the railway track 1. The top slab 2 is pushed and guided hydraulically into its final position underneath the railway tracks 1, in four/six hours. The top slab 2 in its final position thus forms the tunnel roof. The box 3 is then moved hydraulically, excavating the ground at the same time, until it is underneath the concrete slab 2 and in its final position.
In the method of the invention the box 3 is built by the side of the railway track 1, with the top slab 2 larger and separate from the box 3. The slab 2 is supported by the tunnel walls and two piles 4. The slab 2 is then moved hydraulically into its final position underneath the railway tracks 1 to form a support for the rail system 1. Then the box 3 is moved into position hydraulically underneath the slab 2 which will then form the actual tunnel.
Beneficial aspects of the method include:

1 It is not a requirement for an expensive rail support system to be employed for a long period.
2 The rail traffic is not restricted to a relatively slow speed, such as 30 km/h, for a long period.
3 It is a cost effective solution, and it is also a particularly safe solution.

Movement of the tunnel member 3 and the platform member 2 is a two stage process. The hydraulic jacking process is carried out in two stages. First the top slab 2 is moved into position by a hydraulic jacking process. The slab 2 subsequently forms the roof of the tunnel 1. In the second operation the concrete box 3, which forms the tunnel, is moved into position underneath the rail 1.
The slab 2 is larger than the box 3 and is supported by the tunnel walls and by the two piles 4 adjacent to the railway track 1. The larger slab 2 supports the ground better and safer near the tunnel walls.
A sealant may be provided between the vertical side wall of the tunnel member 3 and the top slab 2, which forms the roof of the tunnel.
Mortar may be injected at low pressure between the slab 2 and the vertical side walls of the tunnel member 3 to fill any gaps between the platform member 2 and the top edge of the sidewalls of the tunnel member 3. In certain cases, after the tunnel member 3 is pushed into position the slab 2 may be higher, for example 10cm to 20cm higher, than the top edge of the sidewalls of the tunnel member 3. Any such gap may be filled with mortar to ensure that the slab 2 is supported by the side walls of the tunnel member 3. In addition the ground to the side of the side walls of the tunnel member 3 may come dislodged, and/or unstable, and/or holes/cavities may be formed in the ground. This may adversely affect the stability of the railway track 1 and thus may be dangerous. Mortar may be injected behind the sidewalls of the tunnel member 3 between the side walls and the ground to close or fill any such holes/cavities.
The method of the invention improves performance and safety, and minimises problems.
In the method of the invention, concrete foundation piles 4 are constructed to the side of the rail embankment 1, as close as possible to the rails 1, to support the slab 2. The slab 2 is then constructed, which is to be supported by the piles 4. This slab 2 is a few meters larger than the centreline of the supports 4 to ensure ground stability. The rail 1 is cut, the ballast removed and the slab 2 is slid above the ground. The level is controlled by means of cantilever concrete beams on the piles 4 and the cutting edges on the slab 2.
The rails 1 are reconstructed. The tunnel part 3 is built, and pushed into position with hydraulic jacks, while excavation of the ground under the slab 2 is carried out. Concrete is injected behind the tunnel walls to reinforce the ground.
Additional rail support systems are not necessary. The slab 2 provides the required rail support. No work is required to be done inside the area of the rails 1. In particular, with the invention in suit, it is not necessary to construct support members or support piles in between the tracks of the railway 1. The platform member 2 may be supported by the support members 4 positioned to the side of the railway 1. Traffic stoppage and disruption is therefore minimised. The time required to form the tunnel is minimised, and the risk of train traffic interruption is minimised.
The tunnel 3 is built on free area, not under the slab 2 which is an easier, less dangerous, quicker and less expensive solution. Construction can be done outside the area of the rail 1 without traffic disruption.
It will be appreciated that the tunnel member may be provided in a variety of types of shape/configuration. For example, the tunnel member may be provided in the form of a closed box, and/or may be provided in two halves, and/or may be substantially L-shaped in cross section. The tunnel member may be provided in the form of two or more different elements, and this may be especially useful in the case of a multi tunnel.
It will be appreciated that the slab support member 4 may be provided in the form of a concrete member, and/or in the form of steel piles, and/or in the form of Larsen steel beams, and/or in the form of a curtain wall. It will also be appreciated that any suitable number of support members 4 may be provided. In particular more or less than four pairs of support members 4 may be used. More or less than two pairs of support members 4 may be provided on each side of the railway 1.
One or more of the support members may be configured to receive the platform member as the platform member is pushed onto the upper surface of the support members to rest on the support members. The upper surface of one or more of the support members may have an enlarged area to receive the platform member. In one case the support member may comprise a horizontal cantilever beam fixed to an upper end of a vertical pile, with the cantilever beam being configured to receive the platform member. This arrangement may help the slab to move without sinking. The leading edge of the platform member may be provided in the form of a tapered edge and/or a knife edge to assist sliding of the platform member onto the upper surface of the support members to rest on the support members.
In the embodiment described above the platform member 2 is pushed from one side of the railway 1 and the tunnel member 3 is pushed in the opposite direction from the opposite side of the railway 1. However it will be appreciated that both the platform member 2 and the tunnel member 3 may be constructed in-situ adjacent to the railway 1 on the same side of the railway 1 and may subsequently be pushed in the same direction from the same side of the railway 1.
It will be appreciated that the slab platform member 2 and/or the tunnel member 3 may each be built as a single piece or may each be built in two or more elements. The platform member 2 and/or the slab member 3 may be moved by lifting with cranes, or may be moved on air cushions, or may be moved by pulling with ropes/winches.
It will be appreciated that the tunnel member 3 and/or the platform member 2 may alternatively be constructed at a location remote from the railway 1 and then transported to the railway 1.
The invention has been described in detail above with reference to forming a tunnel beneath a railway 1. However it will be appreciated that the invention may also be employed to form a tunnel beneath other types of travelways, for example roadways, pathways, or waterways such as rivers or canals.
The invention is not limited to the embodiment hereinbefore described, with reference to the accompanying drawings, which may be varied in construction and detail.

Claims

A method of forming a tunnel beneath a travelway, the method comprising the steps of:-
providing a platform member and a tunnel member, the platform member having a width greater than or substantially equal to the tunnel member;

locating the platform member in a location beneath the travelway to maintain the travelway in a substantially stable position; and

moving the tunnel member under the travelway to form the tunnel.
A method as claimed in claim 1 wherein the method comprises the step of supporting the platform member in the location beneath the travelway.
A method as claimed in claim 2 wherein the method comprises the step of providing one or more support members to at least partially support the platform member in the location beneath the travelway, the platform member may be at least partially supported by resting upon the support member, the support member may be provided to a side of the travelway, one or more support members may be provided to a first side of the tunnel member, one or more support members may be provided to a second side of the tunnel member.
A method as claimed in claim 2 wherein the plarform member is at least partially supported in the location beneath the travelway by the tunnel member, the platform member may be at least partially supported by resting upon the tunnel member.
A method as claimed in any of claims 1 to 4 wherein the method comprises the step of excavating at least part of the ground beneath the travelway, part of the ground beneath the travelway may be excavated before locating the platform member in the location beneath the travelway, part of the ground beneath the travelway may be excavated before moving the tunnel member under the travelway.
A method as claimed in any of claims 1 to 5 wherein the platform member is located in the location beneath the travelway by moving the platform member into the location beneath the travelway, the platform member and the tunnel member may be moved from the same side of the travelway, the platform member and the tunnel member may be moved from opposite sides of the travelway.
A method as claimed in any of claims 1 to 6 wherein the method comprises the step of removing at least part of the travelway before locating the platform member, the method may comprise the step of replacing at least part of the travelway, at least part of the travelway may be replaced after locating the platform member, at least part of the travelway may be mounted to the platform member.
A method as claimed in claim 6 or 7 wherein the method comprises the step of easing movement of the platform member and/or of the tunnel member, the method may comprise the step of providing one or more slide members to ease movement of the platform member and/or of the tunnel member, the slide member may ease movement of the platform member and/or of the tunnel member by resting the platform member and/or the tunnel member upon the slide member.
A method as claimed in any of claims 1 to 8 wherein the tunnel member comprises an open-topped member, the tunnel member may be substantially `U'-shaped in cross-section.
A method as claimed in any of claims 1 to 9 wherein the platform member comprises a slab member.
A system for forming a tunnel beneath a travelway, the system comprising:-
a platform member locatable in a location beneath a travelway to maintain the travelway in a substantially stable position; and

a tunnel member movable under the travelway to form a tunnel;

the platform member having a width greater than or substantially equal to the tunnel member.
A system as claimed in claim 11 wherein the system comprises one or more support members to at least partially support the platform member in a location beneath a travelway.
A system as claimed in claim 11 or 12 wherein the tunnel member is configured to at least partially support the platform member in a location beneath a travelway.
A system as claimed in any of claims 11 to 13 wherein the platform member is movable into a location beneath a travelway.
A system as claimed in claim 14 wherein the system comprises one or more slide members to ease movement of the platform member and/or of the tunnel member.