JP2006112137A - Structure of diverging/merging section of branch tunnel, and its construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure of a diverging/merging section of a branch tunnel 2, which can be inexpensively, toughly and safely constructed in a short period of time by narrowing a range for regulating the traffic of an in-service road, corresponding to a cut-and-cover section, on the ground, and a construction method of the structure. <P>SOLUTION: A continuous underground wall body 3 is constructed along a main-line tunnel 1, and the branch tunnel 2 is constructed between the tunnel 1 and the wall body 3 in such a manner as to diverge from/merge into the tunnel 1. In the structure of the diverging/merging section of the branch tunnel 2, earth retaining materials 8 and 9 are elongated toward the wall body 3 from upper and lower sections of the tunnel 1. A lining body of reinforced concrete or steel-frame concrete is constructed in an internal space which is enclosed with the materials 8 and 9, the tunnel 1 and the wall body 3. A diverging/merging section space 18 is formed inside the lining body, so that a diverging/merging section skeleton 17 can be constructed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a structure of a part where a branch tunnel joins from a main tunnel and a construction method thereof.

  Currently, many roads are planned or constructed for the purpose of eliminating traffic congestion in densely populated areas such as the metropolitan area and urban areas. These roads are increasingly being built underground because it is difficult to acquire land on the ground.

Conventionally, when constructing a merging section of a tunnel such as an underground expressway with a shield machine, it has been mainstream to construct it by an excavation method in which a shield tunnel is connected to an excavation merging section excavated from the ground. Also, in recent years, a continuous underground wall for the purpose of water stopping and mountain retaining is constructed outside the passing part of the two tunnels, and after passing through the shield, the two shield tunnels are excavated, A method for disassembling segments and constructing a branch structure has been proposed. As a conventional technique, one described in the following (1) is given as what is described in the patent literature.
(1) Patent Document 1 (Japanese Patent Laid-Open No. 2003-148086)

  The excavable segment is arranged on the side surface where the two tunnels face each other, and a vertical support member that constitutes a branching / merging portion is constructed from the inside of the tunnel as a reinforcing member. A rectangular shield is dug toward one of the tunnels from one of the U-shaped retaining walls constructed at the ramp entrance, and the excavable segment is excavated at the same time as excavating between the tunnels. After translating the rectangular shield with the tunnel, excavate toward the other U-shaped retaining wall at the top of the road, and after excavating the junction, remove one tunnel segment and the reinforcing member, then split the junction and one tunnel segment. And integration.

In Patent Document 1, although a rectangular shield machine is dug between two tunnels, the two connecting tunnels are excavated while disassembling the segment of the connection connecting portion. The horizontal protection of the construction costed the same construction cost and construction period as before, and the safety level of the construction was still old.
JP 2003-148086 A

  However, when the excavation method is used, there is an annoyance that the entire part must be excavated from the ground directly above the junction where the tunnel is combined, and the old construction is still required in terms of construction cost, construction period, and safety. What was left was left.

  Therefore, the present invention has been made in view of the above points, and by reducing the range of traffic regulation on the ground road in service corresponding to the excavated portion, it is inexpensive, robust, and safe in a short period of time. It is an object of the present invention to provide a branching / merging section structure of a branch tunnel to be constructed on the ground and a construction method thereof.

  In order to achieve the above-mentioned problem, the present invention has been proposed, and the invention according to claim 1 constructs an underground continuous wall body along a main tunnel, and the main tunnel and the underground continuous wall It is a junction / junction structure of a branch tunnel constructed by joining and joining from the main tunnel, and a mountain retaining material is extended from the upper and lower portions of the main tunnel toward the underground continuous wall body In addition, a reinforced concrete or steel-concrete lining body is constructed in the internal space surrounded by the mountain retaining material, the main line tunnel, and the underground continuous wall body, and a splitting junction space is formed inside the lining body. Thus, a merging / merging section housing is constructed.

  The invention according to claim 2 uses a pipe roof as the mountain retaining material in addition to the structure according to claim 1, and the pipe roof and the reinforced concrete or steel-concrete covering body are integrated. It is characterized by.

  The invention according to claim 3 is characterized in that, in addition to the configuration according to claim 1 or 2, the underground continuous wall body is a tunnel for earth retaining.

  The invention according to claim 4 is a branch constructed by constructing an underground continuous wall body along the main tunnel, and being split and joined from the main tunnel between the main tunnel and the underground continuous wall body. A method for constructing a junction / merging portion of a tunnel, wherein a mountain retaining material is inserted from an upper and lower portion of the main tunnel, and an insertion tip of the mountain retaining material is extended from the upper and lower portions toward the underground continuous wall body. A support material is disposed on the upper and lower mountain retaining materials while excavating an internal ground surrounded by the upper and lower mountain retaining materials, and reinforced concrete or steel concrete is disposed inside the excavated space and the main line tunnel. A merging / merging section housing having a merging / merging section space is constructed.

  According to a fifth aspect of the present invention, there is provided a branch tunnel constructed by constructing a retaining tunnel along the main tunnel, and splitting from the main tunnel between the main tunnel and the retaining tunnel. A method for constructing a junction / merging portion, inserting a mountain retaining material from an upper and lower portion of the main tunnel, extending an insertion tip of the mountain retaining material from the upper and lower portions toward the earth retaining tunnel, and While excavating internal ground surrounded by upper and lower mountain retaining materials, support materials are arranged on the upper and lower mountain retaining materials, and reinforced concrete or steel concrete is placed inside the excavated space and the main line tunnel. Thus, a merging / merging section housing having a merging / merging section space is constructed.

  According to the first aspect of the present invention, the underground continuous wall body is constructed along the main tunnel, and the main tunnel is divided and joined between the main tunnel and the underground continuous wall body. A branching / merging part structure of a branch tunnel to be constructed, in which a mountain retaining material extends from an upper and lower portion of the main tunnel toward the underground continuous wall body, and the mountain retaining material, the main tunnel, and the underground A reinforced concrete or steel-concrete lining body is constructed in the internal space surrounded by the continuous wall body, and a merging / merging section space is formed inside the lining body, and a merging / merging section housing is constructed. Therefore, the construction of the branching / merging portion is a work in the ground, and a part of traffic restriction is performed at the time of construction of the underground continuous wall body, so that there is little occurrence of traffic congestion or noise. Furthermore, since the underground continuous wall body and the main line tunnel itself serve as a mountain stop and can be prevented from sliding due to soil water pressure, an internal ground can be easily excavated. In addition, the use of the main tunnel lining body as a part of the structure eliminates the need for a new earth retaining work and contributes to the reduction of the construction cost and the construction period.

  According to the invention described in claim 2, in addition to the effect described in claim 1, a pipe roof is used as the mountain retaining material, and the pipe roof and the reinforced concrete or steel-concrete covering body are integrated with each other. Since the above-described upper and lower pipe roofs provide horizontal protection when part of the lining body of the main tunnel is disassembled, the disassembly can be performed more easily and quickly. Furthermore, the pipe roof originally arranged as a temporary structure and a part of the main line tunnel lining body can be effectively used as a part of the merging / disconnecting section main body structure.

  According to invention of Claim 3, in addition to the effect of Claim 1 or 2, since the underground continuous wall body is a tunnel for earth retaining, the earth retaining tunnel is If excavation is carried out by the shield method or propulsion method, the underground continuous wall body does not have to be buried from the ground, so there is no traffic restriction on the used road, so traffic congestion, noise, etc. No pollution. In addition, it is possible to effectively utilize the mountain retaining material originally arranged as a temporary structure, a part of the main tunnel lining body, and the earth retaining tunnel lining body as a part of the merging section housing main body structure. In particular, the earth retaining tunnel can be injected with water from the inside of the earth retaining tunnel, can easily improve the surrounding ground, serve as a mountain retaining, and can prevent sliding due to earth water pressure. Can be excavated.

  According to the invention described in claim 4, the underground continuous wall body is constructed along the main tunnel, and the main tunnel is divided and merged between the main tunnel and the underground continuous wall body. A branch tunnel merging and merging section construction method, wherein a mountain retaining material is inserted from the upper and lower portions of the main tunnel, and an insertion tip of the mountain retaining material is extended from the upper and lower portions toward the underground continuous wall body. And, while excavating the inner ground surrounded by the upper and lower mountain retaining materials, a support material is disposed on the upper and lower mountain retaining materials, and reinforced concrete or the inside of the excavated space and the main line tunnel Since it is characterized by the construction of a merging and merging part frame that has a merging and joining part space by placing steel concrete, the construction of the merging and merging part is an operation in the ground, Some traffic restrictions are imposed, so traffic jams and noise The occurrence of etc. is small. Furthermore, since the underground continuous wall body and the main line tunnel itself serve as a mountain stop and can be prevented from sliding due to soil water pressure, an internal ground can be easily excavated. In addition, the use of the main tunnel lining body as a part of the structure eliminates the need for a new earth retaining work and contributes to the reduction of the construction cost and the construction period.

  According to the invention of claim 5, a branch constructed by constructing a retaining tunnel along the main tunnel, and being merged and merged from the main tunnel between the main tunnel and the retaining tunnel. A method for constructing a merging and merging section of a tunnel, wherein a mountain retaining material is inserted from an upper and lower portion of the main tunnel, and an insertion tip of the mountain retaining material is extended from the upper and lower portions toward the earth retaining tunnel. The support material is disposed on the upper and lower mountain retaining materials while excavating the inner ground surrounded by the upper and lower mountain retaining materials, and reinforced concrete or steel concrete is disposed inside the excavated space and the main line tunnel. Since the merging / merging section frame that has the merging / merging section space is constructed, if the tunnel for earth retaining is excavated by shield method or propulsion method, the underground continuous wall body is buried from the ground. Included Even if there is no need. Therefore, since no construction site is required on the ground surface, traffic is not regulated on the roads used on the ground surface, and therefore no pollution such as traffic congestion or noise occurs. In addition, it is possible to effectively utilize the mountain retaining material originally arranged as a temporary structure, a part of the lining body of the main tunnel, and a part of the lining body of the branch tunnel as a part of the merging section housing body structure. . In particular, the earth retaining tunnel can be injected with water from the inside of the earth retaining tunnel, can easily improve the surrounding ground, serve as a mountain retaining, and can prevent sliding due to earth water pressure. Can be excavated.

Hereinafter, the best mode for carrying out the present invention will be described.
Embodiment 1 of the Invention

  In Embodiment 1 of the present invention, a branching tunnel branching junction structure by a pipe roof construction method and a construction method thereof will be described in detail. 1 to 5 are diagrams according to Embodiment 1 of the present invention. FIG. 1 shows a structure of a horizontal longitudinal cross-section portion in the tunnel length direction of a merging / merging portion, and FIG. 2 or FIG. 3 differs in a merging / merging portion. The structure of the vertical cross section is shown.

  As shown in FIGS. 1 and 2, a main tunnel 1 for roads is constructed in the ground in advance, and a branch tunnel 2 that diverges close to the main tunnel 1 is dug to a predetermined position B and constructed. To do. On the other hand, the underground continuous wall body 3 that supports the extended end of the pipe roof, which will be described later, is installed from the position A to the position D so as to gradually approach the main tunnel 1.

  The branch tunnel 2 is dug by a shield method, but depending on the ground conditions (soil, water pressure, soil cover, N value, etc.) from the main tunnel 1 to the surrounding ground where the branch tunnel 2 is planned to be constructed, The ground is improved, and the ground is called “Surrounded ground 4 with improved ground”. A support material 7a for supporting the lining body of the main tunnel 1 and a bracing support material are temporarily installed.

  Next, an upper plate pipe roof 8 is installed on the upper side of the branch tunnel 2 and a lower plate pipe roof 9 is installed on the lower side from the inner side of the lining body of the main tunnel 1. The tip of each pipe 10 (see FIG. 2 or 3) constituting the upper and lower plate pipe roofs 8 and 9 is extended so as to penetrate or penetrate the underground continuous wall 3. The excavation method for constructing the upper and lower plate roofs 8 and 9 is a screw auger type in which the casing is pushed in the direction of the rotation axis while rotating the casing with an electric motor, and the upper and lower plate pipe roofs 8 and 9 are constructed simultaneously or sequentially. . The upper and lower plate pipe roofs 8 and 9 are inserted into the surrounding natural ground 4 improved in the ground while being connected to the adjacent pipe 10 through a joint (not shown). The underground continuous wall 3 supports the vicinity of the extended tip portion of each pipe 10 of the upper and lower plate pipe roofs 8 and 9.

  In addition, a supplementary ground improvement for water stop was applied to a natural ground near the edge where the upper and lower plate pipe roofs 8 and 9 penetrate or penetrate into the underground continuous wall body 3, 11 ". This supplementary ground improvement is applied simultaneously or sequentially up and down to form a ground with increased waterstop. However, in the case of ground with sufficient water-stopping, it is not necessary to construct this supplemental ground improvement. Further, supplementary ground improvement may be performed around the upper and lower plate pipe roofs 8 and 9 as necessary.

  As shown in FIGS. 2, 3, and 4, the widening operation of the merging / merging portion is advanced. That is, a part 12 of the lining body of the main tunnel 1 is dismantled from around position C, a natural ground (original ground 5) is excavated to the front of the underground continuous wall body 3, and the pile is reinforced by the vertical support material 7b. To do. The cross beam supporting material 6 is abutted and installed horizontally. This is sequentially repeated up to position B of the branch tunnel 2. In this way, with the vertical support material 7b temporarily provided at intervals, the horizontal girder support material 6 is constructed above and below in the excavated space while temporarily supporting the upper and lower plate pipe roofs 8 and 9. The widening operation for removing the part 12 of the lining body is performed in order from the top of the part 12 of the lining body, and a vertical support material is temporarily installed on the upper and lower plate pipe roofs 8 and 9 quickly. The end portion 19 of the main tunnel 1 and the end of the branch tunnel 2 is excavated in order from the end of the end portion 19 and, at the same time as excavation, is piled with a hanging sheet pile or the like. The wife around the branch tunnel 2 is constructed, and finally the shield machine is dismantled. A work stand (not shown) is also temporarily installed when the vertical support material and the horizontal beam support material 6 are temporarily installed.

  As shown in FIG. 5, the merging / merging portion housing 17, which is the main body of the tunnel merging / merging widening portion, is constructed by curing the concrete on the inner wall of the merging / merging portion after curing. Reinforced concrete or steel-framed concrete is cast on the inner part of the lining body of the main tunnel 1, and the merging section side wall 14 is further laid with concrete underneath so that the upper plate pipe roof 8 is buried, and the merging and merging The upper plate 15 casts concrete thereon so that the lower plate pipe roof 9 is also embedded, and the dividing / merging portion lower plate 16 forms the inner wall of the dividing / merging portion housing 17 according to the present invention. The structure of the casing 17 is formed by connecting the upper plate pipe roof 8 and the lower plate pipe roof 9 of the steel frame and the lining body of the main line tunnel 1 so as to be integrated. In order to reduce the risk of collapsing as much as possible, it is preferable that the concrete is placed in order from the lower side of the dividing / merging portion lower plate 16, the dividing / merging portion side wall 14, and the dividing / merging portion upper plate 15. A part of the vertical and horizontal support material is used as a part of the merging / flowing part housing 17. The split / merging part housing 17 is constructed, and the internal space is defined as the split / merging part space 18. After the concrete constituting the split / merging portion upper plate 15, the split / merging portion lower plate 16 and the split / merging portion side wall 14 is cured, hardened and constructed, the temporary vertical support material that is no longer necessary is removed.

  Here, the underground continuous wall 3 does not necessarily need to be constructed in parallel to the main tunnel 1, and as the branch tunnel 2 merges with the main tunnel 1, the main tunnel is narrowed so that the tunnel width of the tunnel branching junction becomes narrower. By placing it close to the side 1, the concrete volume to be placed and the upper and lower plate pipe roofs 8, 9 can be saved.

  FIG. 5 shows a completed drawing of the tunnel junction / merging portion in the first embodiment of the present invention.

  The tunnel merging / merging portion is surrounded by a branch space having a merging / merging portion upper plate 15, a merging / merging portion lower plate 16 and a merging / merging portion side wall 14.

  According to the construction method of the tunnel junction / merging portion, as shown in FIG. 3, the upper and lower plate pipe roofs 8 and 9 and the cross beam supporting member 6 which were “Yamadori materials” are divided into the upper and lower plates 15 and 15 respectively. It is embedded in the subordinate plate 16 to become a “reinforcing member”, and it becomes the tunnel branching junction housing 17 as it is.

  Since the construction work of the upper and lower pipe roofs 8 and 9 and the ground improvement work of the ground 4 are carried out from the main tunnel 1 and the main tunnel 1 and the branch tunnel 2 are connected in the ground to perform the merge, Since the above excavation work is not required, the influence of the in-service facilities on the surface and the necessity of road regulation can be minimized, so pollution such as noise is also minimal.

  In the first embodiment, the cross-sectional shapes of the main shield shield machine and the branch shield machine (not shown) are circular and rectangular, respectively, and the upper and lower plate pipe roofs 8 and 9 are constructed. Any shape such as a horseshoe shape or a circular arc shape may be used, and the shield type is not limited.

  Further, the number of lanes after the main tunnel 1 is in service is not limited to three lanes, and may be other plural lanes or one lane.

The shield cover body may be made of ductile or steel, and the concrete to be cast may be made of high fluidity.
[Embodiment 2 of the Invention]

  In the second embodiment of the present invention, the structure of the branching / merging portion of the branch tunnel by the pipe roof construction method and the construction method thereof will be described with respect to the difference from the first embodiment of the present invention. 6 and 7 are views according to Embodiment 2 of the present invention, and show the structures of the vertical and horizontal cross-sectional portions of the merging / merging portion, respectively.

  As shown in FIG. 7, the earth retaining rectangular tunnels 3 a, 3 b, and 3 c are constructed by a shield method or a propulsion method on the side opposite to the main tunnel 1 when viewed from the branch tunnel 2. An upper plate pipe roof 8 and a lower plate pipe roof 9 are supported by penetrating into the upper earth retaining rectangular tunnel 3a and the lower earth retaining rectangular tunnel 3c, respectively.

  In this second embodiment, there is no need to embed the underground continuous wall body 3 and no land on the ground is used. Therefore, there is no influence of the service facility on the surface, no need for road regulation, and noise and other pollution. Does not occur. The excavation of the tunnel junction / merging section, the construction of the support material, and the construction method of the branch / merging section housing 17 are the same as in the first embodiment.

  Here, the earth retaining rectangular tunnels 3a, 3b, 3c are not necessarily excavated in parallel to the main tunnel 1, and are excavated close to the main tunnel 1 side so as to narrow the tunnel width of the tunnel junction. As a result, the concrete volume and the upper and lower plate pipe roofs 8 and 9 placed by the tunnel junction / merging section housing 17 can be reduced.

  This invention is a civil engineering, building, etc., especially in tunnel excavation methods such as underground highways, to proceed in the underground, not branching, that is, the method of diversion / merging location in the ground, without relying on the ground excavation method Therefore, it can be applied to the geofront for future underground city construction, such as deep underground planning.

It is a tunnel longitudinal direction horizontal longitudinal cross-sectional view which shows the structure of the branch part of the main line tunnel 1 and the branch tunnel 2 which concern on Embodiment 1 of this invention. FIG. 2 is a vertical cross-sectional view taken along the line YY in FIG. 1, showing the structure of the branching junction of the main tunnel 1 and the branch tunnel 2 according to the first embodiment. It is a vertical cross-sectional view which follows the QQ line of FIG. 1 which shows the construction middle stage process of the branching junction of the main line tunnel 1 and the branch tunnel 2 which concerns on the same Embodiment 1. FIG. It is a vertical longitudinal cross-sectional view which follows the XX line of FIG. 3 which shows the construction middle stage process of the branch joint part of the main line tunnel 1 and the branch tunnel 2 which concerns on the same Embodiment 1. FIG. It is a vertical cross-sectional view which shows the construction completion stage of the middle part of the split junction part of the main line tunnel 1 and the branch tunnel 2 which concerns on the same Embodiment 1. FIG. It is a tunnel length direction horizontal longitudinal cross-sectional view which shows the construction completion stage of the branching junction of the main line tunnel 1 and the branch tunnel 2 which concern on Embodiment 2 of this invention. It is a vertical cross-sectional view which follows the SS line | wire of FIG. 6 which shows the construction completion stage of the branching junction of the main line tunnel 1 and the branch tunnel 2 which concern on the same Embodiment 2. FIG.

Explanation of symbols

1 Main tunnel 2 Branch tunnel 3 Underground continuous wall 3a Upper earth retaining rectangular tunnel 3b Middle earth retaining rectangular tunnel 3c Lower earth retaining rectangular tunnel 4 Ground improved surrounding ground 5 Original ground (ground)
6 Cross girder support material 7a Support material for supporting lining body of main line tunnel 1 7b Support material for mountain retaining 8 Upper plate pipe roof (mountain retaining material)
9 Lower plate pipe roof (Yamadome)
10 Pipe 11 Supplementary ground Improved ground near the edge for water stop 12 Part of the lining body of the main tunnel 1 13 Part of the lining body of the branch tunnel 2 14 Side junction 15 Side junction 15 Upper junction 16 Divergence junction lower version 17 Divergence junction housing 18 Divergence space 19 Wife

Claims (5)

A branching and merging section structure of a branch tunnel constructed by constructing a continuous underground wall along a main tunnel and splitting and merging from the main tunnel between the main tunnel and the underground continuous wall. In addition, a mountain retaining material is extended from the upper and lower parts of the main tunnel toward the underground continuous wall body, and in an internal space surrounded by the mountain retaining material, the main tunnel, and the underground continuous wall body, reinforced concrete or A junction / junction structure of a branch tunnel, wherein a steel-concrete lining body is constructed, a merging / merging space is formed inside the lining body, and a merging / merging section housing is constructed. 2. The branching junction structure of a branch tunnel according to claim 1, wherein a pipe roof is used as the mountain retaining material, and the pipe roof and the reinforced concrete or steel-concrete covering body are integrated. 3. The branching tunnel branching junction structure according to claim 1 or 2, wherein the underground continuous wall body is a earth retaining tunnel. A method for constructing a junction / junction part of a branch tunnel constructed by constructing a continuous underground wall along a main tunnel and splitting and joining from the main tunnel between the main tunnel and the underground continuous wall. And inserting a mountain retaining material from the upper and lower portions of the main tunnel, extending the insertion tip of the mountain retaining material from the upper and lower portions toward the underground continuous wall body, and While excavating the enclosed natural ground, support materials are disposed on the upper and lower mountain retaining materials, and reinforced concrete or steel concrete is placed inside the excavated space and the main line tunnel, and a merging junction space A method for constructing a junction / junction section of a branch tunnel, characterized by constructing a junction / merging section housing having A branching tunnel construction method for constructing a earth retaining tunnel along a main tunnel, and branching and merging from the main tunnel between the main tunnel and the earth retaining tunnel, The mountain retaining material is inserted from the upper and lower portions of the main tunnel, the insertion tip of the mountain retaining material is extended from the upper and lower portions toward the earth retaining tunnel, and is surrounded by the upper and lower mountain retaining materials. While excavating an internal ground, a supporting material is disposed on the upper and lower mountain retaining materials, and a reinforced concrete or steel concrete is placed inside the excavated space and the main tunnel to hold a joint flow space. A branching tunnel construction method for branching tunnels, characterized in that a junction section housing is constructed.

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