JP3908464B2 - Construction method of underwater tunnel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for constructing a submarine tunnel by using a concrete / steel structure standing on or in a submarine region on a planned route of a submarine transport tunnel system having a dry shaft. Is constructed from the structure to a depth below the bottom of the water where a branch tunnel surface can be installed.
The technology described here can be adapted for underwater mining applications.
[0002]
[Prior art]
The construction of a long tunnel dug in the bottom of the water takes years and depends greatly on the geology present on the tunnel route. In the case of the English-French Strait tunnel connecting Britain and France, a tunnel excavator (TBM) has been used for seven years to drill through the impermeable layer of chalk geologically suitable soil. On the other hand, the Seikan Tunnel connecting Honshu and Hokkaido under the territorial waters that have the same spacing as the English Channel is a deeper tunnel, but it is a difficult geological condition of a rock body with intense faults, which leads to completion. It took 17 years. These tunnels are the longest underwater tunnels constructed to date, and were drilled from the starting point of each land where both tunnels are connected, namely England and France and Honshu and Hokkaido. In each case, the work face finally collided at an intermediate point to penetrate the route.
[0003]
[Problems to be solved by the invention]
This invention is made | formed with respect to the said prior art, and aims at providing the construction and working method of a new underwater tunnel.
[0004]
[Means for Solving the Problems]
In order to solve the above-mentioned object, the present invention is a method for facilitating construction of a submarine transport tunnel that connects two continents separated by the sea, and tunnel construction is carried out from approximately the middle point of the sea between each of the two continents and the two continents. And tunnel construction from the midpoint is done by installing a low liner at the bottom of the water at a depth suitable for constructing the tunnel;
Towing a concrete or concrete / steel structure with a hole extending in the full length and having a deck facility above the lower liner,
On lower portion liner, the structure of concrete or concrete / steel with the deck equipment, and installed to a hole extending to the structure entire length;
Through a hole of the structure through the tieback liner to the upper end of the lower portion liner; a lower portion liner and tieback liner or al soil and water bound discharged; depth is from the lower end of the lower portion liner tunnels needed for The bore, lower liner, shaft has a diameter large enough for the drilling and downhole equipment to pass through; drilling a cavity at the lower end of the shaft; Assembling; A method for facilitating construction of a submarine transport tunnel comprising constructing a tunnel system extending from a cavity.
[0005]
Said method, a plurality of vertical shafts and cavities, it is preferable to be drilled to the tunnel depth position of the appropriate and optimal tunnel, also the structure is erected on a foundation block of concrete on the sea bed, said block Is preferably delimited by a formwork assembled from a frame and a plate and has an internal matrix of reinforcing bars .
[0006]
Also, it is preferable that the cement slurry is sent into the internal space created by the assembled formwork after being attached to the bottom of the water, and the concrete in the assembled formwork is molded before being attached to the bottom of the water. Is preferred .
[0007]
In order to increase stability and fixation, it is preferred that the excavated area under the mold is made to receive cement slurry, said area coinciding with the area of the structure in plan view . Also, multiple fixed struts are drilled and grooved at the appropriate location of the formwork, and the poured cement will secure the formwork to the bottom of the water instead of or as a supplement to the excavated area under the formwork In order to solidify around the struts, the struts remaining on the bottom of the water and in the entire formwork to be attached thereafter have a suitable length .
[0008]
In addition, drilling equipment and underground equipment are lifted from a large refueling ship and lowered to a structure hole and a shaft to be cut by the structure deck equipment, and the structure is equipment for transporting, treating and disposing of soil. And a ballast tank for controlling the standing structure at the lower end or in the vicinity of the lower end .
[0009]
The method of constructing underwater transport tunnel, temporary lower portion liner, suitable for steel of the working face, the pipe was connected to the outlet to a position suitable liner to eject or grouting fluids, and water of piling device A useful combination of tie-back pillars, installed at the bottom of the water, with the liner reaching the support ground under the soil, for guiding entry for structures, subsequent mechanical coupling and tie-back liner sealing To provide a steel spring on the cross-section for centering the liner with respect to the joint cross-section at the top and the hole in the structure, part of the liner is long enough to protrude from the bottom it is preferable that the tieback liner, incorporated into the liner wall carrying a fluid injection or grouting to sealing region and lower portion liners It was provided with a pipe.
[0010]
The above structure acts as a support facility for the tunnel, serves as emergency entrances and exits for tunnels for workers and passers-by, and is equipped with power, ventilation, pumping, and maintenance over the length of the tunnel that can be used. It is preferable to act as a site for the purpose .
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below with reference to the accompanying drawings.
Construction of a long submarine tunnel requires a detailed survey of the geology of the area so that the most suitable method of excavation can be determined prior to commencement of work. Furthermore, the present invention provides a work shaft that is dug to the depth of the tunnel below the bottom of the water and is used as a means including a work face for tunnel construction and permanent equipment for maintenance of support facilities during work. A detailed survey of the bottom of the water is required.
[0012]
The bottom condition of each site where concrete structures are erected is an important determinant of how to select and install the joints between the bottom and the structure. Water bottom is one of either a little is or is absolutely no rock, or until in deep soil cover of the media leading to the formation that is suitable for supporting the cover soil.
[0013]
Referring to FIG. 1, a tunnel system having one or more major penetration routes and a tunnel 1 that is safely and supplementarily supported provides a dry passage between two areas of land 2 separated by a body of water 3. . A concrete / steel structure 4 used for marine use is erected on a concrete / steel foundation block 5 installed on a bedrock bottom 6. The bedrock bottom 6 is preferably excavated to create a platform for the foundation block 5. The concrete structure has a main hole or shaft 7 that is large enough to allow the drilling and downhole equipment to pass through, and has a deck facility to support the drilling and downhole operations. The deck equipment includes power, ventilation, lifting, transport maintenance and processing and disposal of material cut from the work face. Tunnel worker accommodation may also form part of the deck equipment. Although complementary legs that support the equipment of the structure can be used, the main part of the concrete steel with the main hole is an essential element of the present invention.
[0014]
The shaft 20 supported and drilled by the concrete / steel reinforcement is created from the shaft 7 of the structure through the support to the depth of the tunnel in which the cavity (not shown) is built, Tunnel construction machinery is assembled. In each case where the present invention is used, two additional work faces are provided for tunneling in the opposite direction on the tunnel route. The tunnel in Figure 1 with two concrete structures attached is the conventional method used for long underwater tunnels because it has 3 times the drilling speed due to the availability of 3 times the work face. It is clear that it is completed in about one third of the time required for drilling.
[0015]
The foundation block is of particular importance and coincides with the area of the concrete / steel structure 4 to be erected in plan view, not only with a flat surface for the erection of the concrete structure, Foundation block and bottom generated by fixing to the bottom, guiding and positioning of the concrete structure with steel or concrete / steel outlet, preferably placed in the center of the upper surface of the molding framework into which the concrete is fed, solidifying the concrete and joining to the bottom It is also provided with a hole that is preferably located in the center through a seal in between, and through a spout through the mold to the bottom of the water.
[0016]
Referring to FIG. 2, the procedure for forming the foundation block on the bottom of the rock is described below. The formwork 8 is preferably made of steel and is made from a cut and a plate. The formwork may have an optimal system for efficiently draining seawater that flows into the volume limited by the formwork 8, the bottom 9, the formwork and the hanging skirt 10 at the end of the center hole 11. Preferably it is operated by a valve. The central hole having a protrusion on the mold that functions as the insertion slot 12 for positioning the structure standing thereafter is a hole having a size through which the drilling device and the underground device can subsequently pass. The bottom 9 is a bedrock and is preferably dredged in advance to remove the cover and to excavate a platform for the prepared concrete. The formwork is moved from a large ship at sea and erected at a selected position. The skirt 10 under the mold 8 holds cement slurry in the mold when the pumping operation is completed. Before or during pumping work, a mechanical jack or hydraulic jack, preferably installed under the formwork, that is properly attached to the formwork so that the formwork is horizontal, can be raised as required. Adjust. A matrix made of reinforcing bars is installed in the mold 8, and the reinforcing bars are attached to the mold or set up in advance on the bottom of the water. A suitable cement is made on the water and is preferably fed into the formwork via a vertical flexible pipe, and the seawater present in the formwork is drained both via the valve operating outlet and under the skirt. An excessive amount of cement is input to completely drain the seawater from within the formwork. A uniform, flat block of reinforced concrete with accurate confirmation of the water bottom topography in the formwork results from solidification of the cement slurry. The formwork may be left in place if its presence has little effect on the subsequent erection of the concrete structure and all loads are supported by the block, but with appropriate coating, electrical Corrosion protection and grouting can minimize formwork damage. With a small design change that allows the formwork to be removed from the spigot 12 and the reinforcing bar, the formwork can be removed onto the water as needed. The use of compressed air to discharge water into the mold before introducing cement results in more efficient water discharge. Air is then released as cement enters. This requires an auxiliary ballast held in the bottom of the water on the formwork. In addition, if there are fully available cement mixing and pumping equipment, the foundation can be a foundation that is sized so that the formwork needs to be segmented, and each section can be in turn or simultaneously. Hardened with cement.
[0017]
As an alternative to drilling a hole to install a concrete block, drill the bottom of the bedrock in the location where the formwork is to be installed, and grout multiple struts. When the cement injected into the mold solidifies, it is long enough so that each column protrudes from the bottom into the space in the mold so that the block made is fixed to the column and thereby the block can be fixed to the bottom. I ’ll leave that.
[0018]
It is further preferred to mold the foundation block in the mold before placement in the sea, and then grouting the required blocks, thus requiring a smaller volume of cement and a more reliable concrete quality.
[0019]
Combine elements of the methods cited above manner with technically uniformity as appropriate to the water bottom condition procedure step will be apparent to those skilled in the art. These methods of installing concrete foundation blocks on the bottom of the bed with almost no bedrock or soil cover can be applied to the bottom of a steep slope in order to facilitate the subsequent downhole and underground work of the dry shaft.
[0020]
FIG. 3 shows a concrete / steel offshore structure 4 pulled to a position above the foundation block in a manner commonly used in the bottom oil or gas mining industry (ballast tank controls the height of the structure). ing. The structure has a main hole 7 that is large enough to fit a drilling device, a mine device and a worker, and to attach a device for transporting excavated material.
FIG. 4 shows the structure 4 erected on the foundation block. Boundary between the structure 4 and the base block 5, for subsequent hole 7 is pumped must be grouting in order to perform the seal between the hole 7 and sea water 3. The grouting between the structure and the foundation block is performed through a dedicated pipe made on the wall of the structure for transporting the grouting fluid from the water to the boundary, and the pipe is preferably in the vicinity of the entrance.
[0022]
If the place on the supporting ground is thicker than dredged or removable soil, a different method must be adopted. Referring to FIG. 5, the concrete / steel lower liner 13 is placed in the soil 14 up to the supporting ground 15. The liner then has an internal size through which a drilling device or downhole device can pass and has a wall thickness that can withstand any weight it receives during installation or operation of the construction member. Although not shown, the pipe through which the mud to be injected and the grout to be fixed / sealed can pass is installed in the wall of the liner and is generally fluid from above the water through a resilient pipe 16 attached to the upper end of the liner. Is sent.
[0023]
The excavation section 17 is at the lower end of the liner 13 and is preferably made of steel so that it is generally used in the civil engineering field. The liner 13, it weighs itself, injection, and drilling soil in the liner as necessary to reduce the wall friction, the deeply placed. If it is insufficient to install the liner to a depth that these means as necessary, is attached to the lower portion liner through appropriate temporary tieback column piling device, final installation depth Get a good reach. Once at the support ground, the lower end of the lower liner should be grouting to secure the liner in place and to provide a seal between the highly permeable soil and the liner interior. This lower liner is designed to be long enough to reach the support ground and protrude above the bottom of the water, the protrusion acting as a guide for the concrete structure that is erected thereafter.
[0024]
FIG. 6 shows the structure 4 that is guided by the lower liner 13 projecting to the bottom of the water and is erected on the liner and installed on the surrounding soil. The lower region of the lower liner 13 is fixed by a suitable grout 19 fed through the pipe. Type of centralizer which boring work and casing work smell of oil Te commonly used in order to position around the tubular drill pipe is preferably fixed to the outer surface of the protrusion. These centralizers allow the liner and structure holes to be centered on each other. The liner resists both external compressive forces resulting from soil compression under the structure and hydrostatic pressure differential across the liner wall that exists during the construction of the dry shaft.
[0025]
The concrete / steel tieback liner 18 passes through the main hole of the structure standing on the top cross section of the lower liner 13. Installation and sealing of the machine takes place near the tie back liner and lower liner cross section and a matching pipe is made in the tie back liner so that if necessary, the connection can be further solidified with cement. The tie back liner 18 has a sufficient size to allow the drilling device and the underground device to pass through and a sufficient length to make a boundary at the height of the deck of the structure. The soil under the structure of the type cited in the present invention is well known in the undersea oil mining industry as it becomes harder over time, so the tie back liner has a short upper end and a separable element. Can have. Grout is inevitably used when there is water leakage in the liner shaft. In this particular example, the underlying soil descent results in the settlement of the structure, but the load transfer is mechanically tempered by the structure so that no load transfer to the liner occurs.
[0026]
In FIG. 7, the completion prediction is drawn, and the soil and water in the liner (13, 18) combined by dredging and pumping to form a dry route to the supporting ground 15 after being dug down to the tunnel depth of the shaft. Is removed. The shaft is supported by concrete / steel if necessary, and its size is such that the drilling device and the underground device can pass through. The cavity 21 is made to the tunnel depth, where the tunnel device is assembled and prepared for drilling operations. The liners (13 and 18) essentially comprise a dry passage with the mechanical strength and durability necessary to facilitate the construction of the shaft 20 at the tunnel depth, and by subsequent settling of the concrete structure. Little affected. The tunnel 22 system can now be built from the work face resulting from the arrangement of the present invention. As described above, the liner is used as needed in a concrete structure installed on the bedrock of the rock, and is fixed from the other part of the foundation structure or shaft to the water.
[0027]
The present invention has significant advantages over current methods used to construct and operate long underwater tunnels. The present invention provides an additional work face at an optimal location on the tunnel route, which essentially saves construction time through the maintenance of all the equipment and facilities necessary to perform the work, essentially extending the construction time. This makes it possible to construct a tunnel with a longer length without doing so. Furthermore, this is further strengthened by the use of a protective wall and emergency sealing equipment at the back of each work face near the assembly cavity, so that each tunnel area is drilled separately from the other tunnels. In the event of an irreversible collapse to the bottom of the area under construction, only that particular area will be damaged, but the tunnel is completed by drilling around the collapsed area. Considering the Seikan tunnel with a length of 53 km from the entrance to the exit, one arrangement on the tunnel midpoint in the present invention supplies two additional work face systems in opposite directions in the manner described above. As a result, the construction time is halved from 17 years to eight and a half years (two arrangements reduce the construction time to one-third of the actual time taken). The relationship between the number n of arrangements, the standard build time T and the new build time t using the present invention is t = T / (1 + n).
[0028]
Upon completion of the main submarine tunnel system and the improvement of the shaft including the emergency sealing facility, the present invention provides ventilation, power, maintenance and emergency inspections that were not available in the underwater area of the long tunnel system constructed so far. In addition, it is possible to secure a permanent site for separate and independent maintenance of workers and passers-by exits. The longer the tunnel system, the greater the ventilation requirements and the associated circulating air pressure loss. The circulation system of Seikan Tunnel has a ventilation shaft 23km away. It can be expected that the system of the present invention is arranged at short intervals based on a greatly shortened plan construction time and further ensures complete facility maintenance. There is no longer any inherent limitation due to the length of the tunnel. This is best illustrated by the following example.
[0029]
Korea and Japan have an island at the center, but are about 200 kilometers apart by the Tsushima Strait. In addition to each end point, in addition to one island used as a work base construction base point, and having 10 ocean locations of the present invention, and the average drilling speed per day per work face is 10 meters, There are 24 work faces and each work face must be drilled 8.33 kilometers to complete. The completion of drilling takes 833 days, including one and a half years of equipment movement, and the average total completion time to complete a tunnel system with a length of 200 kilometers connecting the ends is 5 to 6 years. is there.
[0030]
Another area of particular interest is between Hokkaido and Sakhalin, separated by the La Perouse Strait, about 35 kilometers. There is no particular interest in the tunnel transport system itself connecting these islands. However, a fully integrated connection to the Trans-Siberian Railway is achieved through a bridge or tunnel through the 5 km Tartar Strait and the natural extension from there to Komsomolsk na Amur. Transactions between Japan and Europe in 1996 amounted to $ 140 billion, 90% of which use trains. The shipping time on the ship is 5-6 weeks, but if you use the railway on the above route, it will be less than a week.
[0031]
Other routes that are technically possible or more feasible according to the present invention are Australia-Tasmania, Wales-Ireland, Italy-Sicily, but only the second strait tunnel from Bournemouth to Cherbourg. In addition, there is a tunnel system from Finland to Sweden that connects Helsinki and St. Petersburg to the Scandinavian railway network, and a route between Taiwan and China.
[Brief description of the drawings]
FIG. 1 depicts a submarine tunnel system with a marine structure driven and positioned.
Figure 2 depicts a concrete / steel foundation installed at the bottom of a bedrock.
FIG. 3 depicts an offshore structure being pulled to a standing position on a pre-installed foundation block.
FIG. 4 depicts an offshore structure erected on a foundation block.
FIG. 5 depicts the installation work of a concrete / steel liner installed in the bottom of deep soil.
FIG. 6 depicts a concrete / steel offshore structure erected on a liner with a central tieback liner installed in a hole in the offshore structure to create a dry passage in the support ground.
FIG. 7 depicts a shaft and tunnel completed from the structure.
[Explanation of symbols]
1 ... tunnel, 2 ... land, 3 ... water spread, 4 ... offshore structures,
5 ... foundation block, 6 ... bottom of bedrock, 7 ... main hole, 8 ... formwork, 9 ... bottom of water,
10 ... Hanging skirt, 11 ... Center hole, 12 ... Inlet,
13 ... Lower liner, 14 ... Soil, 15 ... Supporting ground,
16 ... pipe, 17 ... digging section, 18 ... tie back liner,
19 ... grout, 20 ... vertical shaft, 21 ... hollow, 22 ... tunnel.

Claims (12)

This is a method of promoting construction of a submarine transport tunnel that connects two continents that are separated by the sea. Tunnel construction is carried out from almost the middle of the sea between each of the two continents and the two continents. Done by installing a lower liner at the bottom position of the depth suitable for construction;
Towing a concrete or concrete / steel structure with a hole extending in the full length and having a deck facility above the lower liner,
On the lower liner , a concrete or concrete / steel structure having the deck equipment is erected so that the hole extends the entire length of the structure;
Through a hole of the structure through the tieback liner to the upper end of the lower portion liner; a lower portion liner and tieback liner or al soil and water bound discharged; depth is from the lower end of the lower portion liner tunnels needed for The bore, lower liner, shaft has a diameter large enough for the drilling and downhole equipment to pass through; drilling a cavity at the lower end of the shaft; Assembling; A method of facilitating construction of a submarine transport tunnel comprising constructing a tunnel system extending from a cavity. A plurality of vertical shafts and cavities, the position of the appropriate and optimal tunnel, methods facilitate the construction of underwater transport tunnels drilled to the tunnel depth is effective in the method of claim 1. 3. A method according to claim 1 or 2, wherein the structure is erected on a concrete foundation block on the bottom of the water, the block being delimited by a formwork assembled from a frame and a plate, and an internal matrix comprising reinforcing bars. A method for facilitating construction of a submarine transport tunnel. The method according to claim 3, underwater transportation tunnel method facilitating the construction of the cement slurry is fed into the interior space created by the assembled mold after attached to the bottom of the water. The method of claim 4, before being attached to the bottom of water, a method facilitating the construction of underwater transport tunnels molded concrete in the assembled formwork. A method according to any one of claims 3 to 5, before forming the base block, to enhance the fixing stability, the area to be excavated beneath the mold, accept cement slurry create Ru bottom of the water transport tunnel method of promoting the construction of the order. The method according to any one of claims 4 to 6, wherein the plurality of fixed support columns are drilled and grooved at a suitable position on the bottom of the water where the formwork is attached , and the poured cement is used as the formwork. Instead of or as a supplement to the excavated area underneath, the struts have a suitable length that remains on the bottom and then in the formwork where it is subsequently attached to solidify around the struts to secure the formwork to the bottom. Promoted construction method of underwater transport tunnel. 8. The method according to any one of claims 1 to 7, wherein the drilling device and the underground device are lifted from the supply large ship and lowered to the structure hole and the shaft to be cut by the structure deck equipment. The structure is equipped with a device for transporting, treating, and disposing of soil, and a method for facilitating construction of a submarine transport tunnel including a ballast tank that controls standing objects at the lower end portion or near the lower end portion thereof. 2. The method of claim 1 wherein the lower liner is suitable for steel facets, pipes with outlets connected to appropriate liner positions for injecting or grouting fluids, and water pile drivers. A useful combination of temporary tie-back pillars installed at the bottom of the water, with the liner reaching the supporting ground under the soil, a guide entry for the structure, subsequent mechanical coupling and sealing of the tie-back liner Have a sufficient length so that a part of the liner protrudes from the bottom of the water to provide a steel spring on the cross section for centering the liner with respect to the joint cross section at the top end and the hole in the structure Promoted construction method of underwater transport tunnel. The method according to claim 9, tieback liner, underwater transportation tunnel method promoting building comprising a pipe incorporated in the liner wall carrying a fluid injection or grouting to sealing region and lower portion liners. 11. The method according to any one of claims 1 to 10, wherein the structure acts as a support facility for the tunnel, serves as an emergency entrance and exit for workers and passers-by tunnels, and further includes power, A method of promoting construction of a submarine transport tunnel that acts as a site for equipment with ventilation, pumping, and maintenance over the length of the tunnel available. The method of claim 6, the area the drilling underwater transport tunnel method facilitating the construction of a match in the region and a plan view of a lower portion of the structure.

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