WO2016041858A1

WO2016041858A1 - Method and installation for mechanical excavation of a cross passage between two traffic tunnels or between two vertical wells

Info

Publication number: WO2016041858A1
Application number: PCT/EP2015/070822
Authority: WO
Inventors: Thomas SILVESTRE; Jean-Noël Derycke; Dominique Michel
Original assignee: Bouygues Travaux Publics
Priority date: 2014-09-15
Filing date: 2015-09-11
Publication date: 2016-03-24
Also published as: AU2015317071A1; FR3025829B1; FR3025829A1; EP3194722A1

Abstract

The present invention relates, in particular, to a method for mechanical excavation of a cross passage (6) between two traffic tunnels (1, 2) or between two vertical wells, characterized by the fact that it comprises a series of steps as follows: i/ a first section (6a) of metal tube equipped with a cutting lip, the internal diameter of said tube being equal to the internal diameter of said cross passage (6), is driven forward from a first (1; 2) of said two tunnels (1, 2) or wells, in the direction of said second tunnel (2; 1) or well; ii/ a second section (6b), having the same diameter, is placed behind said first section (6a) of tube and in extension thereof, and said two sections (6a, 6b) are driven forward together; iii/ operation ii/ is repeated as required; said tube sections (6a, 6b, 6c) being left in place and the materials contained in the tube being evacuated later.

Description

Method and installation of mechanized digging

a communication branch between two traffic tunnels or between two vertical wells. FIELD OF THE INVENTION

The present invention relates to a method of mechanically digging a communication branch connecting two traffic tunnels or two vertical wells in a geological environment subjected to a high water pressure. It also relates to an installation for its implementation, as well as a work obtained by such a method.

BACKGROUND OF THE INVENTION Transport infrastructures are increasingly resorting to tunnels, especially in dense urban areas to compensate for the lack of space on the surface.

For reasons of safety and capacity of the transport infrastructure, a tunnel is very often dedicated to a single direction of traffic. In the case of passenger transport, emergency exits shall be accessible at regular intervals. The optimal spacing between two emergency exits results from a specific study, and is generally between 100 and 500 m.

To meet this requirement, one solution is to go from one traffic tunnel to another by means of what is called "communication branch". By this expression is meant a communication structure linking the two tunnels.

In the case where the infrastructure is located in an underground water table, the watertightness of the structure becomes a critical issue.

The construction of sealed bored tunnels by means of a mechanized tunnel boring machine has become a known problem that companies know how to treat.

However, the difficulty that remains is the realization of a communication branch leading into the main tunnels already built. It is indeed necessary to avoid destroying locally the tightness of these tunnels at the risk of drowning everything.

One of the classic solutions to this problem is to freeze the soil in the area of execution of the communication branch. The freezing temporarily guarantees the watertightness of the soil, which can then be attacked by conventional means of slaughter.

When the covering covering the inner surface of the communication branch is laid, and its junctions with the main tunnels are realized, then the tightness of the whole is ensured. The surrounding soil can then be thawed.

However, the freezing of a terrain is very sensitive to local geotechnics. It follows that implementation deadlines are often poorly controlled, as well as the associated cost of implementation.

This leads to looking for more efficient methods of realization.

Thus, the purpose of the present invention is to propose a method of mechanically digging a communication branch connecting two traffic tunnels while taking into account: the possible presence of an underground water table; the fact that the points of departure and arrival of the branch are tunnels whose sealing must be preserved; the diameter of the communication branch to be made is greater than the usual values of 2000 mm, and rather of the order of 3000 mm or more.

A similar problem arises for the creation of a communication branch between two vertical wells.

SUMMARY OF THE INVENTION

The present invention relates in the first place to a method of mechanically digging a communication branch between two traffic tunnels or between two vertical wells, characterized in that it comprises a series of steps according to which:

i / driving, from a first of said two tunnels or wells, towards said second tunnel or well, a first section of metal tube equipped with a cutting kit, the internal diameter of this tube being equal to the internal diameter of said branch of communication;

ii / it is put in place, behind said first section of tube and in its extension, a second section of the same diameter, and we drive together these two sections;

iii / where appropriate, reiterate the operation i i /;

said tube sections being left in place and the materials contained in the tube being removed later.

Thus, thanks to the invention, metal sections are used which, abutting one after the other, make it possible to form a large diameter horizontal coring device, and to darken it from a first tunnel towards a second tunnel or, where appropriate, a first well in the direction of a second well.

This allows to set up a temporary waterproof coating corresponding to the outer envelope of the final communication branch, without extracting the soil in place and while avoiding the arrival of water in the main tunnel of departure. The first section of the tube is equipped with a cutting kit preferably provided with teeth. It should be recalled that in the field of drilling a cutting kit is a tubular cutting piece mounted at the end of a corer to facilitate its penetration into the ground during a sinking.

According to other nonlimiting and advantageous features of the invention:

the step ii is repeated as many times as is necessary to reach the second tunnel or well;

alternatively, said steps i / to iii / are implemented from each of the tunnels or wells, until said sections meet;

prior to step i / sinking, is fixed against the wall of the first tunnel or well, centered on the longitudinal axis of said branch, a tympanum of reinforcement and holding which has a cylindrical opening of diameter equal to or slightly greater than diameter of said sections;

prior to step i / of sinking, the steps are implemented in which:

- Drills along the longitudinal axis of said branch, a conduit whose tightness is checked vis-à-vis the tunnels or wells and in which a drilling tube of length greater than that of said branch is connected, the ends of said tube making projecting inside each of said tunnels or wells;

- Is positioned against the wall of each of the tunnels or wells, fitted on each of said ends of the drill pipe, a plug which inscribed in a cylinder of diameter slightly less than the inner diameter of said pipe sections;

- On said ends, is placed a clamping means of said cap against the wall of each of said tunnels or wells;

said driving step is implemented by means of a sinking device which moves said sections in a combined movement of translation and rotation;

said driving device is moved and guided by a stuffing device fixed on said tympanum;

- On said pushing device are positioned means for centering, guiding and sealing said sections which cooperate with the outer wall of these sections;

- On the periphery of said plug, are positioned means for centering, guiding and sealing said sections which cooperate with the inner wall of these sections. Another aspect of the invention relates to a mechanized digging plant for a communication branch between two traffic tunnels or between two vertical wells, characterized in that it comprises:

a set of sections of metal tube including a section provided with a cutting kit, the internal diameter of this tube being equal to the internal diameter of said communication branch;

a sinking device which moves said sections in a combined movement of translation and rotation.

Finally, another aspect of the invention relates to a structure obtained after the digging process described above, before removal of the materials filling the tube. Said structure comprises two circulation tunnels or two vertical wells and a tube formed of a plurality of sections extending between said tunnels or between said wells and is characterized in that said tube contains the floor separating said tunnels or wells. guaranteeing tightness with respect to said tunnels or wells.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics and advantages of the invention will appear on reading the following description of a preferred embodiment of the invention. This description is made with reference to the appended drawings in which:

Figure 1 is a cross-sectional view of one of the two tunnels from which it is proposed to build a communication branch;

Figure 2 is a partial longitudinal sectional view of said communication branch and a portion of the two tunnels that can be connected;

Figure 3 is a detail view of a portion of Figure 2;

finally, Figure 4 is a perspective view of the two aforementioned tunnels and the communication branch which makes them join, the devices used for its realization being partially visible in the tunnel to the left of the figure.

DETAILED DESCRIPTION OF THE INVENTION In the description which follows and in the figures which illustrate it, we are interested in the creation of a communication branch connecting two traffic tunnels. The invention however applies similarly to the creation of a communication branch between two vertical wells. As indicated above, in Figure 1 attached is visible in section one of the traffic tunnels that it is proposed to equip a communication branch with another tunnel (not shown in this figure). This tunnel, which can be described as the first tunnel or tunnel departure, bears the reference 1. This is a tunnel whose construction is completed, the wall 100 is formed including segments arranged staggered the each other, as is well known.

This tunnel is equipped in particular with a platform 12 of circulation, ventilation ducts 10, as well as tubes, pipes and / or cables allowing for example the circulation of fluids or information. Other equipment not shown may be in place in the tunnel.

The second tunnel 2 is particularly visible in FIG.

According to the invention, the establishment of the communication branch is carried out without compromising the integrity of tunnels 1 and 2 already built, which makes it possible to avoid generating work, delays and additional costs. For this purpose, and as will be described in detail below, is implemented a corer for cutting the tunnel wall and the floor separating the two tunnels while driving a tube defining the envelope of the branch, without extracting it. stage the materials contained in the tube.

Prior to the construction of the branch, its longitudinal axis XX '(see FIG. 2) is identified by means of topography known to those skilled in the art, such as a theodolite, which allows positioning relative to at the metric point of the tunnel.

Then, on the side of the first tunnel 1, a retention and reinforcing eardrum referenced 4 is positioned. It is in fact a concrete part which has a cylindrical opening 40 of diameter slightly greater than that of the branch that the it is desired to put in place, which is fixed against the wall 100 of the tunnel 1, as is particularly visible in Figures 1 and 2. The face of the tympanum facing the wall has a convex shape complementary to the concave shape of the wall 100 of the tunnel. The connection between the tunnel wall and the tympanum must ensure local sealing and load transfer applied to the tunnel wall when pierced by the corer.

The function of this eardrum is also to ensure the recovery of the forces exerted on the tube 6 constituting the branch, as will be seen below.

At this eardrum 4 is fixed a pushing device for pushing the corer (for example this pushing device comprises the four horizontal and parallel rods 5 which extend towards the inside of the tunnel 1). This function will be explained later in the description.

A similar eardrum can be placed in the tunnel 2. To resume the thrust of the immersed ground cut by the corer in the tunnels 1 and 2 during the realization of the communication branch 6, is placed beforehand in each of the tunnels 1 and 2, a plug 3, respectively 3 '. Each of these plugs is intended to bear against the wall 100, 200 of the corresponding tunnel 1, 2, so as to create a solid and sealed structure when sinking the branch.

To do this, one proceeds along said axis X-X 'to the drilling of a conduit C which is centered on said axis, while ensuring the tightness of the two tunnels. The tube T is then fitted with an outside diameter slightly smaller than the inside diameter of the duct C. This tube T has the particularity of having a length which is much greater than that of the space separating the two tunnels 1 and 2, so that its two opposite ends project into each tunnel.

Is then positioned, by fitting on each of its ends, said plug 3, 3 'which consists of a generally cylindrical contour piece, with a convex rear face, intended to be pressed against the wall 100, respectively 200 tunnels , this in a sealed manner.

Each of the plugs 3 has an axial through opening 30, 30 'of diameter slightly greater than that of the tube T with an increase in diameter 31 which allows to set up a clamping piece B, B' similar to a bolt.

In doing so, it generates pressure forces directed towards one another, which will oppose the pressure forces that will be generated during the manufacture of the branch itself.

Expressed in a different way, the plugs will ensure the holding of the materials during the digging of the branch and resume the efforts due to outbreaks of groundwater and the surrounding soil.

Between each couple eardrum / cap there is a free annular space, which is used for the realization of the branch.

As has been indicated above in the description, the embodiment of the branch will be done using sections of tube 6, three of which are visible in Figure 2 under the references 6a, 6b and 6c.

This is of course a simple embodiment, so that depending on the length of the branch, more than three sections can be used, which is why these are generally referenced 6n.

These sections, all of the same diameter, are dimensioned so that they can be inserted into the annular space present between each tympanic / plug pair. For their implementation, is used on the periphery of the cap 3 of a guide means 32 forming a ring, the outer diameter is equal to the inner diameter of the sections 6a to 6c.

Likewise, on the tubes 5 forming the stuffing device, a crown-shaped guide means 50 is positioned, which has the capacity to be displaced longitudinally along the rods 5 and to have an inside diameter that is very slightly greater than the diameter. outside the pipe sections 6.

Thus, the elements 32 and 50 make it possible to ensure a centering and a guide in translation of the sections in the direction of the space separating the tunnels, as well as the sealing of the sections vis-à-vis the walls of the tunnel.

The first section set up is that which is referenced 6a in Figure 2. This section is not only moved but must also contribute to the cutting of the rock and, more generally, the soil occupying the volume of the future branch. For this purpose, the upstream end of this first section 6a is provided with a cutting kit 60 provided with teeth adapted to the terrain to be crossed.

To enable this section to be moved, a driving device also called "rotator" 7 is positioned as shown in FIG. 7, which has the capacity to impart a rotational movement to said section 6a, allowing the cutting tool 60 to cut the field in front of her. To this is combined a translational movement provided by the pushing device 5. The section 6a can therefore move both in translation and in rotation around the axis X-X '.

When this section 6a is completely engaged inside the space between the two tunnels, the withdrawal is carried out in a reverse movement of the rotator 7 and a new section 6b is positioned, which is itself displaced by the rotator, and which pushes the first section 6a towards the second tunnel.

This operation is repeated as many times as necessary.

As and when the sections are placed, each new section is welded to the section previously inserted, so that all of these sections form a tube that moves in the same combined movement of rotation and translation around the X-X 'axis.

The rotator and the tube formed successive sections together form the corer mentioned above.

In this embodiment which has just been described, the implementation of the sections is done from the first tunnel 1. In this case, when approaching the second tunnel 2, for example local freezing is performed at the right of the plug 3 'to pierce the wall 200 of the second tunnel without altering the seal.

In an embodiment not shown, it is possible to use, in the second tunnel 2, a second rotator 7 similar to that which equips the input tunnel 1 and a The communication branch is then composed of two dark tubes from each tunnel 1 and 2, which meet in an intermediate position. In this case, the tubes are of slightly different diameters to allow penetration of one into the other and thus facilitate the connection of the two tubes.

Local freezing then makes it possible to ensure temporary sealing at the meeting point of the two tubes.

Thus, according to one embodiment of the invention, a method that can be implemented for the realization of this branch may comprise the following steps:

a) positioning in each tunnel 1 and 2 of the X-X 'axis of the communication branch 6;

b) installation in each tunnel 1 and 2 of a tympanum 4 reinforcing the opening of the communication branch in the main tunnel;

c) drilling and installation of the cap retaining system 3 and 3 '; d) placing plugs 3 and 3 'of each tunnel 1 and 2;

e) on the first tunnel side 1, setting up the guidance system for the driving phase;

f) first tunnel side, placing on the plug 3 of the device ensuring the movement and sealing on the inner face of the metal tube; g) first tunnel side, placing on the eardrum 4 of the device ensuring the maintenance and sealing of the outer face of the metal tube;

h) first tunnel side, setting up the translation system connecting the rotator to the tympanum;

i) on the first tunnel side, setting up the rotator 7;

j) first tunnel side, coring a first section 6a of the metal tube equipped with its cutting kit (it begins by cutting the main tunnel coating before entering the ground);

k) on the first tunnel side, at the end of coring of the first section of metal tube, blocking of the metal tube, retraction of the rotator, insertion of the next section, splicing to the previous segment and resumption of coring, and so on until reaching the tube introduced by the second tunnel 2;

l) Local freezing to seal the junction.

Particularly advantageously, the method, because it does not encroach on the entire section of the main tunnels, can be set up in parallel with the digging of the main tunnels by means of mechanized tunnel boring machines.

The sections of tube that constitute the branch 6 are "lost", because they are left in place inside the branch. This one is later free of soil and materials clogging it, and plate on the tube of voussoirs to complete the mechanical strength and tightness of the branch.

Finally, as already explained above, the invention is not limited to the creation of a communication branch connecting two tunnels (said tunnels extending in a substantially horizontal plane) but applies in a manner similar to the creation a communication branch connecting two vertical wells.

Vertical well means a physical functional cavity drilled vertically and connecting two levels of different depth, particularly in the field of tunnels. For example, it may be an access, security or ventilation shaft.

Claims

1. Method of mechanically digging a branch (6) of communication between two tunnels (1, 2) of circulation or between two vertical wells, characterized in that it comprises a series of steps according to which:

i / driving, from a first (1; 2) of said two tunnels (1, 2) or well, towards said second tunnel (2; 1) or well, a first section (6a) of metal tube equipped a cutting kit (60), the inner diameter of this tube being equal to the inner diameter of said communication branch (6);

ii / it is put in place, behind said first section (6a) of tube and in its extension, a second section (6b) of the same diameter, and we drive together these two sections (6a, 6b);

iii / if necessary, repeat operation ii /;

said tube sections (6a, 6b, 6c, 6n) being left in place and the materials contained in the tube being removed later.

2. Method according to claim 1, characterized in that it repeats step ii / as many times as necessary to lead into the second tunnel (1; 2) or well.

3. Method according to claim 1, characterized in that said steps i / iii / are implemented from each of the tunnels (1; 2) or well, until said sections (6a, 6b , 6c, 6n) come together.

4. Method according to one of the preceding claims, characterized in that prior to step i / sinking, is fixed against the wall of the first tunnel (1) or well, centered on the longitudinal axis of said branch (6). ), a tympanum of reinforcement and support (4) which has a cylindrical opening (40) of diameter equal to or slightly greater than the diameter of said sections (6a, 6b, 6c, 6n).

5. Method according to one of the preceding claims, characterized in that prior to step i / sinking:

- Drilling along the longitudinal axis (Χ-Χ ') of said branch (6), a conduit (C) which is checked for tightness vis-à-vis the tunnels (1, 2) or well and in which one emmanche a tube (T) of drilling longer than that of said branch (6), the ends of said tube (T) projecting inside each of said tunnels (1; 2) or well;

- is positioned against the wall (100, 200) of each of the tunnels (1, 2) or well, fitted on each of said ends of the tube (T) drilling, a plug (3) which inscribed in a cylinder of diameter slightly smaller than the inside diameter of said tube sections (6a, 6b, 6c, 6n);

- On said ends is placed a clamping means (B) of said plug (3) against the wall (100, 200) of each of said tunnels (1; 2) or well.

6. Method according to one of the preceding claims, characterized in that said step of sinking is implemented by means of a sinking device (7) which moves said sections (6a, 6b, 6c, 6n) according to a combined movement of translation and rotation.

7. Method according to claim 6 in combination with claim 4, characterized in that said sinking device (7) is moved and guided by a pushing device (5) fixed on said eardrum (4).

8. Method according to claim 7, characterized in that on said pushing device (5) are positioned means for centering, guiding and sealing (50) of said sections (6a, 6b, 6c, 6n) which cooperate. with the outer wall of these sections.

9. A method according to claim 8, characterized in that on the periphery of said plug (3) are positioned means for centering, guiding and sealing (32) of said sections (6a, 6b, 6c, 6n) which cooperate. with the inner wall of these sections.

10. Installation mechanized digging a branch (6) communication between two tunnels (1, 2) circulation or between two vertical wells, characterized in that it comprises:

a set of sections (6a, 6b, 6c, 6n) of metal tube including a section (6a) provided with a cutting kit (60), the internal diameter of this tube being equal to the internal diameter of said communication branch (6) ;

a sinking device (7) which moves said sections (6a, 6b, 6c, 6n) according to a combined movement of translation and rotation.

1 1. Work obtained by the method according to one of claims 1 to 9, comprising two tunnels (1, 2) circulation or two vertical wells and a tube formed of a plurality of sections (6a, 6b, 6c, 6n ) extending between said circulation tunnels or between said wells, characterized in that said tube contains the floor separating said tunnels or wells by guaranteeing tightness vis-à-vis said tunnels or wells.