JP2008057148A - Segment, and construction method for diverging/merging tunnel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a segment which can effectively prevent a shear displacement between complexes of a segment constituted by stacking the plate-like complexes, and a construction method for a diverging/merging tunnel, which can satisfy both construction safety and high construction efficiency. <P>SOLUTION: In the segment 10 capable of being cut by an excavator, the plurality of plate-like complexes 1 etc., in which a plastic foam is reinforced with inorganic fibers, are stacked in such an attitude as to be curved with a predetermined curvature, and an adhesive layer 2 is interposed among the respective complexes 1 and 1. Additionally, a shear resisting means for preventing the shear displacement between the complexes is provided. A pin member 20 passing through each of the complexes, a carbon fiber sheet and a plate material of fiber-reinforced plastics etc., which cover the outer periphery of the segment, and the like are used as the shear resisting means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a segment formed by laminating plate-like composites and a method of constructing a tunnel that uses the segments, and in particular, a segment that can effectively prevent shear deviation between composites and The present invention relates to a method for constructing a merging tunnel that satisfies both construction safety and high construction efficiency.

  When joining tunnels underground, including ramps in underground road tunnels, large-scale excavation methods have been applied in the past.However, land acquisition, impact on ground traffic, longer construction schedules, and so on. Due to the increase in construction costs, a safer and more economical tunnel joining method is desired, and construction companies are studying / developing.

  For example, a technique relating to a junction method and a junction structure of a tunnel proposed as a result of diligent research by the present applicants is disclosed in Patent Document 1, which is known as a technique called FAST method (Free Access Shield Tunnel). It has been. In this method, an FFU segment (called FFU (Fiber Reinforced Famed Urethane)) that can be cut with a cutter bit of a shield machine is incorporated into a part of the lining of the main line shield to be constructed in advance, and this FFU segment is cut. On the other hand, the lamp tunnel merges obliquely with respect to the main line, so that the occupied area can be reduced, and the auxiliary method such as the freezing method can be minimized.

  The FFU segment described above is a segment that has been proposed as a result of intensive studies by the present applicant and the like, and details thereof are disclosed in Patent Document 2. Specifically, a plurality of plate-like composites made of plastic foam reinforced with inorganic fibers are laminated in a curved state with a predetermined curvature, and an adhesive layer or FRP is interposed between the plate-like composites. A segment in which layers are stacked.

  By the way, underground tunnels are steadily increasing in cross section, and the main tunnel of the road that merges with the ramp tunnel has a diameter of about 9 to 16 m, and as the diameter of the tunnel increases, the FFU segment The digit height will inevitably increase.

  In addition to the FAST method described above, for example, a preceding tunnel that extends in the horizontal direction and incorporates an FFU segment in a part thereof is constructed, and an excavation machine for constructing a subsequent tunnel is provided from the inside of the preceding tunnel. There is a so-called upward shield construction method in which a vertical tunnel is constructed by starting upward while cutting. In such an upward shield method, the increase in the digit height of the FFU segment as the tunnel cross section becomes larger is not different from the FAST method.

JP 2005-299087 A Japanese Patent Laying-Open No. 2005-062121

  As described above, as the cross section of the tunnel becomes larger, the digit height of the FFU segment becomes larger, so that the failure mode of the segment becomes a failure mode in which shear failure tends to precede. In particular, in the case of the FFU segment, since a plate-like composite is bonded and configured, a relative shear shift between the composites easily occurs at the bonded portion. When a segment of shear fracture type due to shear deviation is used, it leads to brittle fracture before the segment is cut while the segment is being cut by an excavator, and in the segment area that should originally be cut. Cutting will not be performed sufficiently. Furthermore, due to the shear deviation of the segment, the rigidity of the segment region that should not be cut can be reduced, and water stoppage cannot be ensured. In order to cope with such a problem, an auxiliary method such as a freezing method is required, and the use of the FFU segment reduces the auxiliary method and increases the economic efficiency.

  The present invention has been made in view of the above-described problems, and even when the height of the FFU segment is increased with an increase in the cross section of the tunnel, a segment that is difficult to cause shear fracture such as shear deviation, It aims at providing the construction method of the tunnel which joins and can satisfy both construction safety and high construction efficiency by using a segment.

  In order to achieve the object, the segment according to the present invention is a segment that forms a part of a wall of an underground tunnel and can be cut by an excavator, and is a plate-like shape in which a plastic foam is reinforced with inorganic fibers. A plurality of composites are stacked in a curved posture with a predetermined curvature, and the segment is configured by interposing an adhesive layer between the composites. Further, in order to prevent shear displacement of the composites The shear resistance means is provided.

  The segment of the present invention is a segment in which shear resistance means is provided on the FFU segment described above. A fiber reinforced plastic layer (FRP layer) can also be interposed between the composites. For example, an FRP layer in which a resin such as a polyester resin or an epoxy resin is reinforced with a reinforcing material such as a mat or cloth can be applied. Examples of the mat and cloth include those obtained by processing glass fibers, carbon fibers, aramid fibers, and the like.

  When the composite that constitutes the segment is composed of a composite material in which plastic foam is reinforced with inorganic fibers, when it is used in the excavation part of a segment tunnel (the merged part cut by a shield machine) Compared with the concrete segment, the excavation speed by the shield machine increases and the excavation process can be shortened. The composite described above is preferably formed from a material obtained by reinforcing a foam made of a hard urethane resin with long glass fibers. In this case, it is possible to use a composite material in which the long glass fibers are filled in a monofilament state in one direction in the urethane foam, that is, the long glass fibers are dispersed one by one in one direction. Even when excavated, there is no problem that the long glass fiber cuts are clogged with screws. In addition, a plate-shaped composite material in which urethane foam is reinforced with long glass fibers is superior in bending strength and compressive strength. Both urethane foam and glass fibers are relatively inexpensive, and moreover compared to concrete. There is an advantage that it is lightweight.

  As described above, because the digit height (thickness) is increased by making the segment corresponding to a large cross-section tunnel, the composite is superior in bending strength and compressive strength. The possibility of having a dangerous failure mode preceded by shear failure due to a typical shear deviation is increased.

  The segment of the present invention is provided with appropriate shear resistance means that does not cause this shear deviation, thereby reducing the possibility of occurrence of shear fracture due to shear deviation. Even if the beam height is increased, a segment having a high strength corresponding to a large-section tunnel and having an easy cutting property can be obtained by adopting a structure in which shear deviation hardly occurs.

  Here, as one embodiment of the shear resistance means, the outer periphery of the segment is covered with a covering material including a carbon fiber sheet and a plate material having a predetermined strength including a fiber reinforced plastic. Means can be applied.

  The carbon fiber sheet is a sheet material formed by weaving carbon fibers (a material in which carbon fibers are bundled, mainly made of acrylic fibers) in a cloth and molding with a urethane resin or the like. Carbon fiber reinforced plastic (CFRP) can be used as the fiber reinforced plastic. As other coating modes, there is a method of molding the outer periphery of the segment with an appropriate resin material.

  By covering the outer periphery of the segment with these sheet material or plate material, shear deviation between the composites can be effectively prevented. In particular, when a sheet material is used, the thickness of the sheet material is as small as several millimeters. Therefore, the use of the coating material does not cause a problem that the dimension of the segment becomes too large.

  Further, as another embodiment of the shear resistance means, a means is provided in which a plurality of corresponding positions are provided in each of a plurality of corresponding positions in the composite body, and a pin member is inserted and fixed in this pin hole. Can be applied.

  Here, for the opening position of the pin hole, a form provided only in the vicinity of the end portion of the segment, a form in which the pin holes are dispersed and opened over the entire range of the segment, or the like can be applied. Further, the pin member is formed from an appropriate material having a predetermined strength (particularly shear strength) such as steel or concrete, and the length thereof can be set to about the digit of the segment. The pin member may be a bolt penetrating the segment, and the nut may be tightened from both sides of the segment with a nut. The material of the pin member (and its shear strength) and the number of pin members to be installed (the number of pin holes to be opened) are determined according to the design shear force and the like.

  Here, as the material of the pin member, it is molded from a material having a predetermined strength and capable of being cut by an excavator, including a material formed by reinforcing a foam made of a hard urethane resin with a long glass fiber. Preferably it is. By forming the pin member from a material that can be easily cut, it is possible to completely eliminate the problem that the pin member cut by the screw of the shield machine is clogged during cutting.

  In addition, the shear resistance means is the means described above (the first means in which the outer periphery of the segment is covered with a covering material including a carbon fiber sheet and a plate material having a predetermined strength such as fiber reinforced plastic. Resistance means), the above-described means (second resistance means) comprising a pin hole opened at a corresponding position of the composite laminated in a plurality of sheets, and a pin member inserted and fixed in the pin hole; Of course, it may be a form having both.

  Further, another embodiment of the segment according to the present invention is a segment that forms a part of a wall of an underground tunnel and can be cut by an excavator, and the segment is an inner side that is formed in a curved shape. A plate-like composite comprising a body and an outer body, and an intermediate body interposed between the inner body and the outer body, both of which are plastic foam reinforced with inorganic fibers Are laminated in a curved posture with a predetermined curvature, and an adhesive layer is interposed between each composite, and the intermediate body is either a resin foam or a honeycomb structure resin body. It consists of one type, and further comprises shear resistance means for preventing shear displacement of the composite.

  The segment of the present invention suppresses an increase in the weight of the segment as much as possible by forming a sandwich structure by interposing a separate intermediate body between the curved inner body and outer body formed by laminating a plurality of composites. However, the segment height can be increased.

  Here, the intermediate body is made of a solid foam made of, for example, PE-PS, acrylic, PVC, or urethane resin, and is bonded to each of the inner body and the outer body via an epoxy resin adhesive. Applicable. Moreover, by using a resin body having a honeycomb structure, it is possible to provide an intermediate body that has a structural strength and can further reduce the weight as compared with a solid case. As the shear resistance means, various means described above can be applied. Needless to say, when a pin member is used as the shear resistance means, the pin holes are opened at corresponding positions of the inner body, the intermediate body, and the outer body.

  According to the segment of the present invention, the weight of the entire segment can be suppressed as much as possible even when the girder height increases, and a segment that does not have a failure mode preceded by shear failure can be obtained.

  Further, according to the present invention, a method for constructing a merging and tunneling tunnel is as follows. When an underground tunnel such as a shaft, road tunnel, or railway tunnel is constructed as the first tunnel in the ground, a separate second tunnel is used. The above segment that can be cut by an excavator is used at the location where the merging and merging from one tunnel is performed, and the other general part is a first segment using either a steel segment, a concrete segment, or a segment in which they are combined. A first step of constructing the tunnel, and a step of constructing the second tunnel by excavating the excavator from the first tunnel while cutting the segment that can be cut, or a second step of excavating the excavator and the second Any of the steps of arriving at the first tunnel while constructing the tunnel and joining the first tunnel while cutting the segments that can be cut A second step of either made from one step, characterized in that at least comprises a.

  The above-described segment that is easy to cut by an excavator and has shear resistance means is incorporated into a predetermined portion of the first tunnel constructed in advance, and the second tunnel is connected to the second tunnel while cutting this segment. By splitting and merging into one tunnel, it is possible to extremely reduce the possibility that the segment will cause a brittle shear fracture type before and after cutting and during cutting. Therefore, it is possible to realize construction safety and efficient merging and merging in the tunnel merging and merging. Further, since the fracture range does not extend far beyond the cutting range due to the shear deviation between the composites, it is not necessary to carry out an auxiliary method such as a freezing method over a wide range.

  As can be understood from the above description, according to the segment of the present invention, it is possible to improve the construction efficiency from the ease of cutting by the excavator, even when the tunnel has a large cross section and the segment digit height is large, The possibility of brittle shear fracture due to shear shear can be reduced as much as possible. Therefore, according to the method for constructing a merging and merging tunnel according to the present invention using this segment as a part of the preceding tunnel, an efficient and safe tunnel merging and merging construction can be realized. Therefore, it is possible to reduce the scope of application and reduce the scope of application, and to realize economical tunnel merging and construction.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view showing a situation where a shield machine is starting from a tunnel incorporating the segment of the present invention, and FIG. 2 is an exploded perspective view of an embodiment of the segment of the present invention. FIG. 3 is an enlarged view of the internal structure of the complex constituting the segment. FIG. 4 is a schematic diagram of a bending test of a segment, FIG. 4a shows a load loading state, FIG. 4b shows a failure state of a conventional segment model, and FIG. 4c shows a failure state of the segment of the present invention. 5 to 8 are perspective views of other embodiments of the segment of the present invention, respectively. FIG. 9 is a diagram for explaining the tunnel construction method of the present invention. FIG. 9a shows the first step. FIG. 9b shows the second step.

  FIG. 1 is a diagram illustrating a situation in which a shield machine is starting from the inside of a preceding tunnel incorporating a segment of the present invention. The preceding tunnel is configured by assembling a general part of a segment S made of concrete or steel in the ring direction and the longitudinal direction of the tunnel (X direction). Is constructed in advance by incorporating the segment 10 of the present invention. The segment 10 is made of a material that can be easily cut with a cutter bit of the shield machine SM. Therefore, the shield machine SM efficiently cuts the segment 10, 10,. You can dig into the ground to build (Y direction).

  FIG. 2 is a diagram showing an embodiment of the segment of the present invention. The segment 10 is formed by laminating plate-like composites 1, 1,... Curved with a predetermined curvature (or radius of curvature), and the composites 1, 1 are bonded to each other by the adhesive layer 2. Composed. The internal structure of the composite 1 is shown in FIG. 3, and the composite 1 is obtained by reinforcing a plastic foam 31 such as a hard urethane resin with long glass fibers 32. Examples of such a complex include Eslon Neo Lumber-FFU (manufactured by Sekisui Chemical Co., Ltd.). The thickness of the composite 1 is about 10 mm or less. An FRP layer in which a resin such as a polyester resin or an epoxy resin is reinforced with a reinforcing material such as a mat or cloth can be interposed between the composites 1 and 1.

  Returning to FIG. 2, pin holes 11 penetrating in the thickness direction are formed in the corresponding positions on the entire surfaces of the composites 1, 1,... Are stacked and fixed, through holes are formed in the thickness direction of the composite 1. The segment 10 is manufactured by inserting and fixing pin members 20, 20,.

  Here, the pin member 20 can be manufactured from a material such as concrete having at least a desired shear strength. However, the pin member 20 is made of a material in which a foam made of a hard urethane resin that is the same material as the composite 1 is reinforced with long glass fibers. Preferably it is configured. In this case, since the excavator can easily cut the pin member 20 as well, a problem that the pin member meshes with the cutter bit cannot occur. In addition, the installation location of the pin member may not be the entire range of the segment as shown in the drawing, but only the vicinity of the end of the segment. The thickness and number of the pin members are determined by the shear strength per one piece and the design shear force per one segment.

[Bending test and its results]
Next, based on FIG. 4, the outline and results of the segment bending test conducted by the inventors will be described.

  The inventors support the segment model M1 (conventional segment) formed by laminating and bonding the composites 1, 1,... And the model M2 including the segment 10 shown in FIG. A bending test was carried out in which two loads were loaded (see FIG. 4a). In addition, as for the loading method of a load, it can test by arbitrary concentrated load or distributed load aspect according to the aspect which the cutter of an excavator acts on a segment.

  FIG. 4 b shows a test result (destruction state) in the case of the conventional segment model M 1, and FIG. 4 c shows a destruction state of the model M 2 including the segment 10.

  As shown in FIG. 4b, in the case of the conventional segment model M1, the adhesive layer between the composites 1 and 1 causes a lateral shift while peeling (shear shift), and the segment M1 becomes brittle while the shift proceeds. I found it to destroy.

  On the other hand, according to the segment model M2 shown in FIG. 4c, a plurality of bending cracks C,... Extending in the thickness direction of the member are generated in the tensile region below the segment, and a typical bending fracture appearance is exhibited. In the case of bending failure, as shown in the figure, the member gradually plastically deforms while a large number of bending cracks C,...

  The reason why the segment model M2 has led to a bending failure instead of a shear failure is that the pin member 20 inserted and fixed therein improves the shear resistance against shear deviation, and as a result, a bending failure-preceding failure mode is achieved. It can be determined that this is because

  5 to 8 are views showing other embodiments of the segment of the present invention. A segment 10A shown in FIG. 5 includes the internal structure shown in FIG. 3 and a block body (inner body 5, outer body 4) formed by bonding composites 1, 1,... Curved with a predetermined curvature. An intermediate body 6 interposed between the inner body 5 and the outer body 4 is configured. Pin holes are formed in the corresponding positions of the inner body 5, the outer body 4, and the intermediate body 6, and the segment 10A is formed by inserting and fixing the pin member 20 into the through hole formed by the corresponding pin hole. Composed.

  The intermediate body 6 is formed of a solid foam made of PE-PS, acrylic, PVC, or urethane resin, and is bonded to the inner body 5 and the outer body 4 via an epoxy resin adhesive. Although not shown, as another embodiment of the intermediate body 6, it can be formed of a resin body having a honeycomb structure.

  By constructing the segment while sandwiching the intermediate body made of the resin body between the outer body and the inner body, the digit height of the segment can be increased while suppressing an increase in the weight of the segment as much as possible.

  The segment 10B shown in FIG. 6 is the same as the segment 10 shown in FIG. 2, except that the pin member is inserted and fixed in the through hole, and a plurality of composites 1, 1,. The carbon fiber sheet 7 is wound around the metal to enhance the effect of preventing the shear deviation between the composites. In addition, when the carbon fiber sheet 7 is wound around the outer periphery of the segment 10 shown in FIG. 2, the shear resistance is further increased.

  In FIG. 7, a through-hole is provided only in the vicinity of the end of the laminate made of the composites 1, 1,..., And a steel bolt 20A is inserted into the through-hole, and the end is tightened with a nut 20B. The segment 10C is shown. When steel bolts are in the full range of the segment, the problem of the bolts engaging with the excavator cutter bit is likely to occur. It is good to arrange only in the vicinity.

  FIG. 8 shows a segment 10D formed by covering the outer periphery of a laminate made of composites 1, 1,... With plate members 81, 82 made of fiber reinforced plastic or the like while bonding them. In FIG. 8, the end face to which the plate material is not bonded may be covered with the same plate material.

  According to the above segments 10 to 10D, since the material can be easily cut with a shield machine, it is possible to efficiently construct the junction and junction of the tunnel, and the segment has a brittle shear. It is possible to reliably prevent a decrease in construction safety due to breakage (shear deviation).

  FIG. 9 is a diagram illustrating a construction method in which a segment 10 is incorporated in a part thereof to construct a preceding tunnel, and a shield tunneling machine is started from the preceding tunnel into the ground to construct a subsequent tunnel.

  As shown in FIG. 9a, the preceding tunnel T1 is constructed by incorporating segments 10,... Into a part of the preceding tunnel T1 (where the shield machine starts). At the stage where the preceding tunnel T1 has been built up to the state where the segments 10,... Are incorporated at predetermined locations, a ring support 91 is installed inside the preceding tunnel T1, as shown in FIG. And carry in the shield machine SM.

  The shield tunneling machine SM cuts the segments 10,... And constructs the trailing tunnel T2 extending in the direction orthogonal to the preceding tunnel T1 while digging in the ground.

  In addition to the method for constructing the junction / junction portion of the tunnel shown in FIG. 9, a separate shield machine that has constructed the subsequent tunnel arrives at the connecting portion of the preceding tunnel (where the segment 10 is incorporated), and the segment There is also a method in which a merging / merging portion is constructed by entering the preceding tunnel while cutting 10. Furthermore, as in the FAST method described above, there is also a method of constructing a branching / merging part by obliquely joining a shield machine that constructs a subsequent lamp tunnel with respect to a connecting part of a preceding main tunnel.

  According to the construction method of the tunnel to be merged and merged according to the present invention, since the segment of the present invention is incorporated at the junction and junction of the preceding tunnel, brittle shear failure of the segment is less likely to occur, and construction safety is improved. Can be increased. Further, the brittle fracture of the segment affects the area other than the area scheduled to be cut by the excavator and causes the water stoppage and strength of the segment to decrease. Therefore, a wide range of auxiliary construction methods (freezing construction method, etc.) are required, and the construction economy, which is the original purpose of adopting the FFU segment, is impaired. However, according to the construction method of the present invention, since the possibility that the segment is brittlely fractured is extremely low, it is possible to cope with only a narrow range as much as possible without requiring a separate auxiliary method. Can be realized.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. They are also included in the present invention.

It is the schematic diagram which showed the condition where the shield machine starts from the tunnel incorporating the segment of this invention. It is a disassembled perspective view of one embodiment of the segment of the present invention. It is an enlarged view of the internal structure | tissue of the composite_body | complex which comprises a segment. It is an outline figure of a bending test of a segment, (a) shows the time of load loading, (b) shows the destruction situation of the conventional segment model, and (c) shows the destruction of the segment of the present invention. It is the figure which showed the condition. It is a perspective view of other embodiment of the segment of this invention. It is a perspective view of further another embodiment of the segment of the present invention. It is a disassembled perspective view of other embodiment of the segment of this invention. It is a perspective view of further another embodiment of the segment of the present invention. It is the figure explaining the construction method of the tunnel of this invention, Comprising: (a) is a figure which showed the 1st process and (b) showed the 2nd process.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Composite body, 2 ... Adhesive layer, 31 ... Plastic foam, 32 ... Glass long fiber, 4 ... Outer body, 5 ... Inner body, 6 ... Intermediate body, 7 ... Carbon fiber sheet 10, 10A, 10B, 10C, 10D ... segment, 11 ... pin hole, 20 ... pin member, SM ... shield machine, T1 ... leading tunnel, T2 ... trailing tunnel

Claims (8)

A segment that forms part of the wall of the underground tunnel and that can be cut with an excavator,
A plurality of plate-like composites reinforced with plastic foam with inorganic fibers are laminated in a posture curved with a predetermined curvature, and the segment is configured with an adhesive layer interposed between each composite, The segment further comprises a shear resistance means for preventing shear displacement of the composite. A segment that forms part of the wall of the underground tunnel and that can be cut with an excavator,
The segment is composed of an inner body and an outer body formed in a curved shape, and an intermediate body interposed between the inner body and the outer body,
Both the inner body and the outer body are laminated in a posture in which a plastic composite is reinforced with inorganic fibers and is bent with a predetermined curvature, and an adhesive layer is interposed between the composites. The intermediate body is made of any one of a resin foam and a honeycomb-structured resin body, and further includes shear resistance means for preventing shear displacement of the composite. A feature segment.   The segment according to claim 1 or 2, wherein the composite is formed from a material obtained by reinforcing a foam made of a hard urethane resin with long glass fibers.   The said shearing resistance means consists of the outer periphery of a segment being coat | covered with coating | covering materials including the board | plate material provided with the predetermined intensity | strength including a carbon fiber sheet and fiber reinforced plastics. Segments described in.   A plurality of stacked composites are provided with pin holes at a plurality of corresponding positions, and the shear resistance means is the pin hole and a pin member inserted and fixed in the pin hole. The segment according to any one of claims 1 to 3.   The shear resistance means corresponds to the first resistance means in which the outer periphery of the segment is covered with a covering material including a fiber reinforced plastic or a plate material or a carbon fiber sheet, and a plurality of laminated composites. 4. The device according to claim 1, comprising: two resistance means including a pin hole established at a position where the pin hole is provided and a second resistance means including a pin member inserted and fixed in the pin hole. Segments described in.   The pin member is made of a material having a predetermined strength and capable of being cut by an excavator, including a material obtained by reinforcing a foam made of a hard urethane resin with a long glass fiber. The segment according to 5 or 6. When underground tunnels such as shafts, road tunnels, and railway tunnels are constructed as the first tunnel in the ground, a separate second tunnel is cut by an excavator at a location where the first tunnel is merged. The first tunnel is constructed by using the segment according to any one of claims 1 to 7 and using a steel segment, a concrete segment, or a segment in which they are combined for other general parts. A first step of:
A step of constructing a second tunnel by excavating the excavator from the first tunnel while cutting the segment that can be cut, or a first tunnel while constructing the second tunnel by excavating the excavator A method of constructing a merging tunnel, comprising at least a second step consisting of any one of the steps of arriving and merging the cuttable segment into the first tunnel.

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