JP2002038897A - Tunnel construction method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance workability in a tunnel connection method, a tunnel execution method, a tunnel construction device, a press-in machine for a steel shell, and a steel plate. SOLUTION: The tunnel construction device 10, in which connected to the tail part 11a of excavating machine body 11 in a shield machine 10a a forward end connecting part 29a of a press-in machine body 29 in a steel plate press-in machine 10b is bendably by connecting pins 30, performs excavation work and steel shell assembling work by the shield machine 10a and steel plats insertion work by the machine 10b concurrently in parallel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel connection method and a tunnel construction method for constructing a tunnel having a relatively large cross section by connecting an adjacent tunnel to an existing tunnel, and a tunnel used at this time. Related to construction equipment, steel shells and steel plate press machines.

[0002]

2. Description of the Related Art For example, as a construction method of constructing a tunnel having a relatively large cross section, a plurality of small tunnels having a rectangular cross section are excavated by a shield excavator, and these small tunnels are connected in a rectangular frame shape to form a central portion. A method of constructing a large section tunnel by discharging earth and sand is known.

In this tunnel construction method, when connecting adjacent small tunnels, a steel plate is bridged between a steel shell of one existing tunnel and a steel shell of the other existing tunnel,
Each steel shell and the end of the steel plate were fixed and connected by welding or bolts, respectively.

[0004]

However, in this conventional tunnel construction method, apart from the excavation work of the ground by the shield excavator and the assembling work of the steel shell, the steel tunnel of the adjacent existing tunnel is separated. The work of hanging and fixing the steel plate is required, and the device is required after the work, and the workability is not good because the work is different.

The present invention solves such a problem, and a tunnel connection method, a tunnel construction method, a tunnel construction device, and a tunnel construction method for improving workability of a tunnel connection operation.
It aims at providing a steel shell and a steel plate press-fitting machine.

[0006]

According to a first aspect of the present invention, there is provided a tunnel connecting method, comprising: When adjacent to an existing steel shell, a steel plate is inserted into the ground from the steel shell in the steel plate press machine toward the existing steel shell and connected.

In the tunnel connecting method according to the second aspect of the present invention, the steel shell assembling operation by the excavator and the steel plate inserting operation by the steel plate press-in machine are performed simultaneously in parallel.

Further, according to the tunnel construction method of the present invention, when a steel plate press machine following the excavator is adjacent to an existing steel shell, the steel plate press-fitting method is carried out with the excavator. A steel plate is inserted into the ground from the steel shell inside the machine to the existing steel shell and connected, and excavation and steel shell assembly work by this excavator and steel plate insertion work by the plate press machine are sequentially repeated to achieve the planned tunnel. A steel shell is provided around the steel shell, and after removing earth and sand in a portion surrounded by the steel shell, the steel shell and the steel plate are integrally fixed.

According to a fourth aspect of the present invention, there is provided a tunnel construction apparatus, wherein a cutter for excavating the ground is mounted at a front portion of the excavator body having a propellable tubular shape, and a cylindrical shape is provided at a rear portion of the excavator body. And a steel plate press-fitting machine for inserting a steel plate into the ground toward an adjacent existing steel shell is connected to a rear portion of the excavator body. .

Further, in the tunnel construction apparatus according to the invention of claim 5, the steel plate press-fitting machine is characterized in that it is flexibly connected to a rear portion of the excavator body.

Further, in the tunnel construction apparatus according to the invention of claim 6, the steel plate press-fitting machine is characterized in that it is flexibly connected to a rear portion of the excavator body by a plurality of connecting pins.

Further, in the tunnel construction apparatus according to the present invention, the steel plate press-fitting machine is integrally connected to a rear portion of the excavator body.

The steel shell according to the invention of claim 8 is a steel shell assembled in a cylindrical shape along the inner wall surface of the excavation tunnel, and a steel plate for connecting to an adjacent existing steel shell is movably supported. It is characterized by having been done.

According to a ninth aspect of the present invention, there is provided a steel plate press-fitting machine according to the present invention, wherein a steel sheet positioned on an outer peripheral portion of a first existing steel shell and supported by the first existing steel shell is adjacent to the first existing steel shell. It is characterized by being inserted into the ground toward the second existing steel shell.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic cross-sectional view of a tunnel construction device according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view of a connecting portion between a shield excavator and a steel plate press machine, FIG. FIG. 4 is a sectional view of a main part showing a support structure of the extrusion jack in the steel plate press-in machine, FIG. 5 is a schematic diagram of a steel shell, FIG. 6 is a description of a tunnel connection method by the tunnel construction device of the present embodiment, and FIG. The outline of the large section tunnel constructed by the tunnel construction method is shown.

In this embodiment, as shown in FIG. 7, a plurality of small tunnels T
1, T2, and T3 are excavated and formed in a frame shape, and thereafter, a large tunnel T is built in the inside by discharging earth and sand inside.

As shown in FIGS. 1 to 4, the tunnel construction apparatus 10 is configured such that a steel plate press-fitting machine 10b is flexibly connected to a rear portion of a shield excavator 10a. The shield excavator 10a has a function of excavating the ground in front while propelling, and a function of assembling a steel shell, which will be described later, in a tubular shape in the excavated tunnel space. On the other hand, the steel plate press machine 1
No. 0b has a function of inserting and sliding a sliding steel plate between a pair of steel shells in order to connect adjacent small tunnels formed by assembling a cylindrical steel shell.

In this shielded excavator 10a, the excavator body 11 has a rectangular cylindrical shape, and the bulkhead 1
2 is fixed to prevent intrusion of excavated earth and sand into the excavator body 11. The excavator body 11 has the bulkhead 1
2, a cylindrical support frame 13 extending in the excavation direction is fixed, and a support shaft 14 is fixed to a front end portion of the support frame 13. A bracket 15 is fixed, and sub-mounting brackets 16 are fixed on both sides thereof. An upper drum cutter 17 and a lower drum cutter 18 are rotatably supported by the main mounting bracket 15 and the sub mounting bracket 16 with a pair of upper and lower horizontal shaft centers along a lateral direction substantially orthogonal to the excavation direction. A chamber 19 is formed between the drum cutters 17 and 18 and the bulkhead 12.

The upper drum cutter 17 and the lower drum cutter 18 have substantially the same configuration, are symmetrical to each other, and are located in front of the excavator body 11 in front. The upper and lower drum cutters 17 and 18 are fixed at predetermined intervals along the circumferential direction, respectively, with the cut-spokes 20 and 21 attached thereto.
2, 23 are attached. In this case, the rotation loci of the tips of the cutter bits 22 and 23 in the upper drum cutter 17 and the lower drum cutter 18 overlap by the length S, but the mounting positions of the cutter bits 22 and 23 are shifted in the rotation direction. The cutter bits 22, 23
Comrades do not interfere. Each of the drum cutters 17 and 18 can be driven to rotate by a built-in drive motor.

A plurality of shield jacks 24 are arranged in a circumferential direction around the rear inside of the excavator body 11, and the shield jacks 24 extend rearward in the excavation direction and are pressed against a steel shell S described later. Thereby, the excavator main body 11, that is, the shield excavator 10a can be advanced by the reaction force. Further, a swivel ring 25 is supported at the rear of the excavator body 11 so as to be swivelable.
A lifting platform 26 is supported by the lifting platform 26, and an erector device 27 is supported by the lifting platform 26. The erector device 27 is located in the space between the excavator body 11 advanced by the shield jack 24 and the existing steel shell S. A new steel shell S can be assembled. A tail seal 28 is provided along the circumferential direction on the inner peripheral surface of the rear end of the excavator body 11 to slide against the outer peripheral surface of the steel shell S to prevent water from entering the inside.

The chamber 19 formed in the excavator main body 11 has one end open at the other end of a mud sending pipe and a mud discharging pipe (not shown) extending outside the tunnel construction apparatus 10. An agitator for stirring and mixing the excavated earth and sand with the muddy water is installed near the opening of the pipe.

On the other hand, in the steel plate press-fitting machine 10b, the press-fitting machine main body 29 is formed in a rectangular cylindrical shape like the excavator body 11 of the shield excavator 10a, and the front end connecting portion 29a is connected to the excavator main body 1a.
One tail portion 11a is flexibly connected by a plurality of connection pins 30 and a seal member 31 is interposed therebetween. On the left and right sides of the upper and lower inner surfaces of the press-fitting machine main body 29, four extrusion jacks 32 and 33 for extruding the slide steel plate C are respectively disposed along a horizontal direction orthogonal to the longitudinal direction of the tunnel. Have been. Each of the extrusion jacks 32, 33 is connected to a bracket 34, 35 whose base end is fixed to the press-fitting machine main body 29 by a connecting shaft 3.
6, 37 while each drive rod 38, 3
Press-fitting attachments 40 and 41 are connected to the distal end of 9, and the press-fitting attachments 40 and 41 are formed with notches 42 for locking the slide steel plate C. In addition, adjacent to the extrusion jacks 32 and 33, this extrusion jack 3
Extrusion jack pressing devices 43 and 44 having springs for pressing the press fitting attachments 40 and 41 sides 2 and 33 against the outer peripheral surface side of the steel shell S are provided.

As shown in FIG. 5, the steel shell S for forming the small tunnel is formed by assembling a plurality of steel plates in accordance with the sectional shape of the small tunnel. The device 27 performs this. A pair of guides 45 are fixed to the upper and lower surfaces of the steel shell S on the left and right sides thereof, and the slide steel plate C is movable by the guides 45 along a horizontal direction perpendicular to the longitudinal direction of the tunnel. Supported. Therefore, after the steel shell S is assembled in the excavator body 11 by the erector device 27 of the shield excavator 10a, when the steel plate press-in machine 11b moves to the position of the steel shell S, the extruding in the press-in machine body 29 is performed. The sliding steel plates C are located on the left and right sides of the jacks 32, 33.

Outlet slits 46 and 47 for extruding the slide steel plate C to the outside of the excavator main body 11 corresponding to the slide steel plate C are formed in the upper and lower portions on the left and right sides of the press-fitting machine main body 29. Is formed. Around the outlet slits 46 and 47, seals (not shown) for preventing earth and sand or muddy water from entering the inside are provided. Further, a tail seal 4 is provided on the inner peripheral surface of the rear end of the press-fitting machine main body 29 so as to slide on the outer peripheral surface of the steel shell S to prevent water from entering inside.
8 are mounted along the circumferential direction.

Further, six steel shell support jacks 49, 50 are provided on the left and right inner surfaces of the press-fitting machine body 29, respectively.
Is extended, the press-fitting machine main body 29 and the steel shell S are integrated, and the extrusion reaction force of the slide steel plate C can be obtained by the extrusion jacks 32 and 33. Further, a hydraulic supply source 51 is mounted on a rear portion of the excavator main body 11, and is connected to each of the extrusion jacks 32 and 33 through a hydraulic pipe 52. The hydraulic supply source 51 may be used to drive the shield jack 24 or the elector device 27. In this case, the piping system is simplified as compared with piping outside the machine.

In the above-described embodiment, the four extrusion jacks 32 and 33 are provided at each of the upper and lower sides and the left and right sides of the press-fitting machine main body 29. This is because the jacks 32 and 33 may be used, and four extrusion jacks 32 and 33 may be used to obtain a large pushing force. Then, a predetermined number of push-out jacks may be detachably provided, and may be attached to a position to be used when necessary. Further, the shape of the press-fitting attachments 40, 41 of the extrusion jacks 32, 33 is not limited to the cutout 42, as long as the slide steel plate C can be securely locked and pushed out. A pair of guides 45 are provided to movably support the slide steel plate C on the steel shell S. However, not only the guide 45 but also a long hole of the slide steel plate C is engaged with a guide pin of the steel shell S. It may be.

Hereinafter, a tunnel construction operation by the tunnel construction apparatus 10 of the present embodiment configured as described above will be described.

First, as shown in FIGS. 1 to 4, when the shield jack 24 is extended by a predetermined stroke while the upper and lower drum cutters 17 and 18 are driven to rotate by a built-in drive motor in the shield excavator 10a. The excavator body 11 moves forward by the reaction force against the existing steel shell S, and the drum cutters 17 and 18 that are driven to rotate in opposite directions excavate the ground in front. Then, one or more of the shield jacks 24 is contracted to form a space between the steel shell S and the existing steel shell S, and the erector device 27 assembles a new steel shell S into a cylindrical shape in this space. Go. By repeating this operation, a tunnel having a rectangular cross section can be continuously constructed.

By the operation of the shield excavator 10a, as shown in FIG. 7, first, the lower three tunnels T1 are constructed, the left and right three tunnels T2 are constructed, and finally, the upper tunnel is constructed. By constructing T3, the small tunnels T1, T2, T3 are formed in a frame shape, and thereafter, the large tunnel (construction plan tunnel) T is constructed inside by discharging the soil inside.

As described above, a plurality of small tunnels T1, T2,
When forming T3 adjacently in a frame shape, the shield excavator 1
0a and the adjacent tunnels T1, T by the steel plate press 10b in synchronism with the excavation work by the ground 0a and the assembling work of the steel shell S.
2. A slide steel plate C is stretched over T3 (steel shell S) to connect them.

That is, as shown in FIG. 6, when the steel shells S of the small tunnels T1 on both sides are assembled, the tunnel construction device 1
No. 0 forms the small tunnel T1 in the meantime, and simultaneously connects the steel shell S to be assembled and the existing steel shell S of the small tunnel T1 adjacent to the left and right by the slide steel plate C. In this case, the drum cutters 17 and 1 of the shield excavator 10a are used.
The excavator body 11 moves forward by excavating the ground in front by 8, and the erector device 27 assembles the steel shell S. In parallel with this work, the steel plate press-in machine 10b extends the corresponding extrusion jacks 32, 33 with respect to the slide steel plate C previously supported on the upper and lower surfaces of the steel shell S, and slides through the press-fit attachments 40, 41. Then, the slide steel sheet C is pushed out of the press-fitting machine main body 29 through the outlet slits 46 and 47 and inserted into the ground. Then, each slide steel plate C becomes the steel shell S of the adjacent tunnel T1.
Move along the upper and lower surfaces, and both are temporarily connected.

The small tunnels T1, T
2 and T3, and tunnels T1, T2 and T
When the steel shells S of the plurality of small tunnels T1, T2, and T3 are installed around the planned tunnel by press-fitting the slide steel plate C into the steel shell S of the third tunnel and bridging it, the small tunnel T1 , T2, and T3 are removed by a construction machine (not shown), and then the steel shell S and the slide steel plates C are integrally fixed by welding or bolts to construct the large tunnel T. be able to.

In the above embodiment, the cross-sections of the small tunnels T1, T2, T3 are different. This is because a plurality of shield excavators having different cross-sections are operated simultaneously or with a time difference. Is explained. In the present invention, not limited to this embodiment, each of the small tunnels T1, T2, T3 can be constructed with the same sectional shape.

As described above, in the tunnel construction method using the tunnel construction apparatus 10 of the present embodiment, the following operational effects can be obtained as compared with the conventional method.

(1) A steel plate press-fitting machine 10b having a press-fitting function of inserting a slide steel plate into an adjacent existing steel shell is flexibly provided at the rear of a shield excavator 10a having a ground excavating function and a steel shell assembling function. Because of the connection, the shield excavator 10a and the steel plate press-fitting machine 10b can be reduced in size and weight, can be reduced in cost, and can cope with curved tunnel construction. (2) Extrusion jacks 32 and 33 for extruding the slide steel plate C
Is disposed on the press-fitting machine main body 29, the extrusion reaction force can be reliably received by the press-fitting machine main body 29 itself, and the peripheral structure of the extrusion jacks 32, 33 can be reduced in size and weight. (3) Since the extrusion jacks 32 and 33 are mounted on the inner surface of the press-fitting machine main body 29 so as to correspond to the slide steel plates C, the support structure of the press-fitting attachments 40 and 41 becomes easy. (4) Since the slide steel plate C is movably supported on the outer peripheral surface of the steel shell S by the guide 45, it can be easily pressed into a predetermined position. (5) Attachment 4 for extrusion jacks 32 and 33
Since the extrusion jack pressing devices 43 and 44 for pressing the 0 and 41 sides to the outer peripheral surface side of the steel shell S are provided, the press-fit attachments 40 and 41 can be easily set.

FIG. 8 shows a schematic sectional view of a tunnel construction apparatus according to a second embodiment of the present invention. Note that members having the same functions as those described in the above-described embodiment are denoted by the same reference numerals, and redundant description will be omitted.

In the present embodiment, as shown in FIG. 8, the tunnel construction device 60 includes a front end connecting portion 29a of the press-fitting machine main body 29 of the steel plate press-fitting machine 10b on a tail portion 11a of the excavator body 11 of the shield excavating machine 10a. Is the joining pin 6
1 are integrally connected. Other configurations are almost the same as those of the tunnel construction device 10 of the first embodiment described above. Therefore, the tunnel construction device 60
The structure of itself can be simplified.

In the above embodiment, the steel plate press-fitting machine 2 is used.
Although the slide steel plate C is extruded by the extrusion jacks 32 and 33 of No. 9, a motor or the like may be used. Also, the cutters mounted on the front part of the excavator body are the drum cutters 17 and 18, but may be disk-shaped cutter heads.

[0040]

As described in detail in the above embodiment, according to the tunnel connection method of the first aspect of the present invention, a steel plate press-in machine subsequent to the excavator accompanying the excavation by the excavator and the assembly of the steel shell. When the steel plate was adjacent to the existing steel shell, steel plates were inserted into the ground from the steel shell in the steel plate press machine to the existing steel shell and connected, so ground excavation work, steel shell assembly work, and steel plate insertion The workability and safety can be improved by separately performing the steel shell connection work.

According to the tunnel connection method of the second aspect of the present invention, the steel shell assembling operation by the excavator and the steel plate inserting operation by the steel plate press machine are performed simultaneously in parallel, so that the operation efficiency is improved. Can be.

According to the tunnel construction method of the third aspect of the present invention, when the steel plate press following the excavator is adjacent to the existing steel shell with the excavation by the excavator and the steel shell assembly, the tunnel inside the steel plate press is installed. Steel plates are inserted into the ground from the steel shell to the existing steel shell and connected, and the excavator excavation, steel shell assembly work, and steel plate insertion work are sequentially repeated, so that the steel is placed around the planned tunnel. After the shell was installed and the soil surrounded by the steel shell was removed, the steel shell and the steel plate were fixed together, so that the construction work of the tunnel could be carried out continuously. Excavation work and steel shell assembling work and steel shell connecting work by inserting a steel plate can be performed in parallel, and this work can also be performed inside the apparatus, so that workability and safety can be improved.

According to the tunnel construction apparatus of the present invention, the cutter for excavating the ground is mounted on the front of the excavator body having a propellable cylindrical shape, and the tubular steel shell is assembled on the rear. Attaching the equipment and connecting a steel plate press-fitting machine that inserts a steel plate into the ground toward the adjacent existing steel shell, separately perform ground excavation work, steel shell assembly work, and steel shell connection work by inserting the steel plate. This can reduce the size of the device and reduce the cost, as well as improve workability and safety.

According to the tunnel construction apparatus of the fifth aspect of the present invention, the steel plate press-fitting machine is flexibly connected to the rear portion of the excavator body, so that it is possible to appropriately cope with a curved tunnel construction.

According to the tunnel construction apparatus of the sixth aspect of the present invention, the steel plate press-fitting machine is flexibly connected to the rear portion of the excavator body by the plurality of connection pins, so that the tunnel construction can be performed with a simple configuration for a curved tunnel construction. We can respond appropriately.

According to the tunnel construction apparatus of the present invention, since the steel plate press is integrally connected to the rear part of the excavator body, the apparatus can be simplified.

According to the steel shell of the eighth aspect of the present invention, the steel plate for connecting to the adjacent existing steel shell is movably supported on the steel shell assembled in a cylindrical shape along the inner wall surface of the excavation tunnel. In addition, it is not necessary to prepare a separate connecting steel plate at the time of connecting the existing steel shells, so that the apparatus can be simplified and the workability can be improved.

According to the ninth aspect of the present invention, the steel plate positioned at the outer peripheral portion of the first existing steel shell and supported by the first existing steel shell is directed to the adjacent second existing steel shell. Since it is configured to be inserted into the ground, it is not necessary to carry the connecting steel plate into the apparatus at the time of connecting the existing steel shells, so that the apparatus can be simplified and workability can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a tunnel construction device according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a connecting portion between a shield excavator and a steel plate press machine.

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4 is a sectional view of a main part showing a support structure of an extrusion jack in the steel plate press-fitting machine.

FIG. 5 is a schematic view of a steel shell.

FIG. 6 is an explanatory diagram of a tunnel connection method by the tunnel construction device of the present embodiment.

FIG. 7 is a schematic diagram of a large-section tunnel constructed by the tunnel construction method of the present embodiment.

FIG. 8 is a schematic sectional view of a tunnel construction device according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Tunnel construction apparatus 10a Shield excavator 10b Steel plate press-in machine 11 Excavator main body 17,18 Drum cutter 24 Shield jack 27 Electa apparatus 29 Press-in machine main body 30 Connecting pin 32,33 Extrusion jack 40,41 Press-in attachment 43,44 Push-out jack press Equipment 45 Guide S Steel shell C Slide steel plate T Construction plan Large tunnel 60 Tunnel construction equipment 61 Joining pin

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mitsuru Shinohara 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda Construction Corporation (72) Inventor Akira Usami 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda (72) Inventor Takeshi Yanagura 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda-ken Incorporated (72) Inventor Seiichi Matsushita 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda (72) Inventor Makoto Ukegawa 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda Takeshi Incorporated Corporation (72) Minoru Motoki 1-1-7-1 Kyobashi, Chuo-ku, Tokyo Toda Takeshi 2D054 AA05 AB05 AC02 AD19 BA02 2D055 AA10 BA01 BB03 DA11 GB01

Claims (9)

[Claims] When a steel plate press following the excavator is adjacent to an existing steel shell, the steel shell in the steel plate press moves from the steel shell in the steel plate press toward the existing steel shell. A tunnel connection method characterized in that a steel plate is inserted into the ground for connection. 2. The tunnel connection method according to claim 1, wherein a steel shell assembling operation by the excavator and a steel plate insertion operation by the steel plate presser are performed simultaneously in parallel. 3. When a steel plate press machine following the excavator is adjacent to an existing steel shell in association with excavation and steel shell assembly by the excavator, the steel plate inside the steel plate press machine is directed toward the existing steel shell. The steel shell is installed around the planned tunnel by repeating the excavation and steel shell assembling work by the excavator and the steel plate insertion work by the plate presser in sequence. A method for constructing a tunnel, comprising: fixing the steel shell and the steel plate integrally after removing earth and sand in a portion surrounded by a shell. 4. An excavator body having a tubular shape capable of propulsion is provided with a cutter for excavating the ground at a front portion thereof, and an erector device for assembling a cylindrical steel shell is provided at a rear portion of the excavator body. And a steel plate press for inserting a steel plate into the ground toward an adjacent existing steel shell is connected to a rear portion of the excavator body. 5. The tunnel construction apparatus according to claim 4, wherein the steel plate press-fitting machine is flexibly connected to a rear portion of the excavator body. 6. The tunnel construction apparatus according to claim 5, wherein the steel plate press-fitting machine is flexibly connected to a rear portion of the excavator body by a plurality of connection pins. 7. The tunnel construction apparatus according to claim 4, wherein the steel plate press is integrally connected to a rear portion of the excavator body. 8. A steel shell assembled in a cylindrical shape along an inner wall surface of an excavation tunnel, wherein a steel plate for connecting to an adjacent existing steel shell is movably supported. 9. The method according to claim 9, wherein the first steel shell is located at an outer peripheral portion of the first steel shell.
A steel plate press-in machine for inserting a steel plate supported by an existing steel shell into the ground toward a second existing steel shell adjacent to the first existing steel shell.