JP7355684B2 - Joint structure of hexagonal segments - Google Patents

Description

The present invention relates to a joining structure of hexagonal segments, and in particular, when forming a lining of a shield tunnel by assembling hexagonal segments in series in the axial and circumferential directions of a tunnel, adjacent hexagonal segments The present invention relates to a joint structure of hexagonal segments provided at joints of segments.

The shield method using a shield excavator is widely used as a method for constructing various tunnels in urban areas and plain areas. In the shield construction method, the face at the tip of the shield excavator is pressed down by mud, muddy water, pressurized air, etc., and the ground is excavated using a cutter, and the tunnel is connected in the axial and circumferential directions behind the shield excavator. By sequentially assembling the segments, a lining is formed that covers the inner peripheral surface of the tunnel, and a shield jack is pressed against the front end of the assembled lining to obtain a reaction force while reaching from the starting shaft. This is a construction method in which a tunnel is constructed underground towards a shaft.

In recent years, from the perspective of improving construction efficiency, segments forming the lining that covers the inner peripheral surface of tunnels have been provided with hexagonal planar shapes instead of the generally used segments with rectangular frontal shapes. A shield construction method using hexagonal segments may be adopted (for example, see Patent Document 1 and Patent Document 2). The hexagonal segment has a face-side joint surface and a well-head-side joint surface that are arranged in parallel, and a face-side diagonal joint surface that is arranged in a V-shape so as to connect the ends on both sides of these joint surfaces. and a pair of V-shaped circumferential joint surfaces consisting of diagonal joint surfaces on the wellhead side (see FIG. 1). The hexagonal segment is attached to the face-side joint surface and the diagonal face-side joint surface of the hexagonal segment that is assembled in advance on the rear side in the tunnel excavation direction, and on the face-side joint surface and the face-side diagonal joint surface of the hexagonal segment that is subsequently assembled on the forward side in the tunnel excavation direction. The tunnel is constructed by overlapping the joint surface on the tunnel entrance side and the diagonal joint surface on the shaft entrance side, while alternately protruding the isosceles trapezoidal portions of each hexagonal segment, which are the forward half portions in the tunnel excavation direction. They are arranged in a honeycomb shape in the axial and circumferential directions and are sequentially assembled (see, for example, Patent Document 3 and FIG. 4).

In addition, in the shield construction method using hexagonal segments, a shield jack is pressed against the face side joint surface of the isosceles trapezoidal portions of the hexagonal segments that protrude alternately, and while the shield excavator is excavating while taking the reaction force. In parallel with this, it is possible to assemble the succeeding hexagonal segments in the area between the adjacent isosceles trapezoidal sections against which the shield jack is pressed (for example, see Patent Document 3, Figure 4). ), unlike the shield construction method using segments with a rectangular planar shape, the process of digging with a shield excavator is not interrupted for each ring to assemble the segments, but while assembling hexagonal segments, By continuously excavating with a shield excavator, it becomes possible to carry out shield work efficiently.

Furthermore, in the shield construction method using hexagonal segments, the connection between adjacent hexagonal segments is the joint surface on the face side, the joint surface on the wellhead side, the diagonal joint surface on the face side, the joint surface by the diagonal joint surface on the wellhead side. Since this is done using a connecting bolt that is attached through the gap (see, for example, Patent Document 1, Patent Document 2, and Patent Document 3), it is possible to attach the lining body by segments having a rectangular planar shape. It is possible to prevent unevenness that appears on the inner circumferential surface due to a bolt box or the like for fastening the connecting bolts from being formed on the inner circumferential surface of the lining body made of hexagonal segments. This also allows the inner circumferential surface of the lining to be maintained in a smooth state, so it is preferable to further apply a secondary lining inside the lining made of hexagonal segments with an anti-corrosion layer on the inner surface. There is no need for construction, and the inner circumferential surface of the lining made of hexagonal segments can be used as the inner circumferential surface of the tunnel, and the constructed shield tunnel can be used, for example, as a sewer pipe for water circulation, or as a temporary rainwater drain. This makes it possible to effectively utilize the tunnel as a reservoir tunnel for storing water.

Patent No. 2596666 Japanese Patent Application Publication No. 9-273395 Patent No. 3253870 Patent No. 4646501

On the other hand, when a shield tunnel constructed using hexagonal segments is used as a tunnel for distributing water, such as a sewer pipe or a tunnel for a reservoir that temporarily stores rainwater, the ground around the tunnel In addition to preventing groundwater from entering the tunnel interior, it is necessary to prevent water flowing inside the tunnel from leaking to the tunnel exterior through the joints between adjacent hexagonal segments. There is.

On the other hand, it is possible to omit the secondary lining, for example, by using concrete segments with an integrated secondary lining and preferably having a rectangular front shape and having an anti-corrosion layer on the inside surface. When forming sewer pipes using the shield construction method, in addition to preventing underground water from entering the tunnel (water stoppage), it also prevents sewage flowing inside the tunnel from leaking to the outside. A caulking material for shield segments has been developed (for example, see Patent Document 4).

According to the caulking material for shield segments of Patent Document 4, at the joint portion of adjacent segments, a seal recess is provided in a portion of the joint surface on the outside of the tunnel, and a water-expandable sealing material is sandwiched therein. A joint is provided at the edge of the joint surface on the tunnel inner surface side, and the caulking material for the shield segment is sandwiched between the joints, and the water-expandable sealing material sandwiched in the seal recess prevents water from entering the tunnel from outside. In addition to preventing groundwater from entering, the caulking material sandwiched between the joints prevents water (such as sewage) inside the tunnel from leaking out from the joints of the segments.

By using the caulking material for shield segments of Patent Document 4 also at the joints of adjacent hexagonal segments, water inside the tunnel can be prevented from leaking from the joints of the hexagonal segments to the outside of the tunnel. However, in the case of hexagonal segments, a plurality of such hexagonal segments are arranged in a honeycomb shape with their positions shifted by half in the excavation direction in the axial and circumferential directions. Since it is difficult to determine the direction of stress on the directional joint surface, unexpected unbalanced loads are easily applied to the joint surface due to pressure from the surrounding ground. In addition, in the case of hexagonal segments, if caulking material is sandwiched in the joint provided at the edge of the tunnel inner peripheral surface side of a pair of overlapping joint surfaces at the joint part, the caulking material will be compressed. By being sandwiched in such a way that it can swell, or by having swelling properties, a reaction force is applied that spreads the edge on the inner circumferential surface of the tunnel, thereby promoting uneven load and causing the outer circumferential surface of the joint surface to expand. There is a possibility that an excessive unbalanced load will be generated on the side edges, and it is expected that this will cause damage to the edges on the outer peripheral surface side of the joint surfaces of the hexagonal segments. If the edge on the outer circumference side of the joint surface of the hexagonal segment is damaged, repair is difficult because the outer circumference of the hexagonal segment is covered by the surrounding ground, and it is difficult to repair the edge of the hexagonal segment from the surrounding ground. Since it is easy for groundwater to infiltrate into the tunnel, it is necessary to focus on and develop solutions to the technical issues when attaching caulking material to the joints of hexagonal segments.

The present invention can effectively prevent water inside the tunnel from leaking to the outside of the tunnel from the joints of adjacent hexagonal segments, and can also prevent damage to the edges of the joint surfaces of the hexagonal segments on the outer circumferential side. It is an object of the present invention to provide a joining structure of hexagonal segments that can effectively avoid such occurrences.

The present invention provides a face side joint surface and a wellhead side joint surface that are arranged in parallel, and a face side diagonal joint surface that is arranged in a V-shape so as to connect the ends of both sides of these joint surfaces, respectively. When forming the lining of a shield tunnel by assembling hexagonal segments each having a pair of V-shaped circumferential joint surfaces consisting of a diagonal joint surface on the tunnel entrance in the axial and circumferential directions of the tunnel. , a joint structure of hexagonal segments provided at the joint of adjacent hexagonal segments, which is interposed between each joint surface of the adjacent hexagonal segments and is continuous over the entire circumference of each hexagonal segment. A sealing material is sandwiched between the joint surfaces of adjacent hexagonal segments, and is compressed over the entire circumference of each hexagonal segment. The caulking material is sandwiched in a compressed state or in a state in which it can absorb moisture and swell, and is interposed between the edge portions on the outer peripheral surface side of each joint surface of adjacent hexagonal segments, and is in a compressed state or in a state in which it can swell. When the caulking material, which is expandable and deformable, exerts a reaction force that spreads the inner peripheral edge of the tunnel, a buffer material that absorbs the reaction force acts on each hexagonal segment. a hexagonal shape that is sandwiched all around the hexagonal segment, and in a region between the caulking material and the cushioning material, the sealing material is continuously provided over the entire circumference of each hexagonal segment; The above object has been achieved by providing a segment joining structure.

In the hexagonal segment joining structure of the present invention, the buffer material is attached in advance to the outer circumferential side edge portion of the wellhead side joint surface and both of the wellhead side diagonal joint surfaces in each hexagonal segment. By assembling these hexagonal segments in series in the axial and circumferential directions of the tunnel, the buffer material can be attached to the edge portion of the outer peripheral surface side of each joint surface of the adjacent hexagonal segments. It is preferable that the hexagonal segment be interposed therebetween and sandwiched around the entire circumference of each hexagonal segment.

Further, in the joint structure of hexagonal segments of the present invention, the caulking material is applied to the tunnel inner peripheral surface side edge portions of the joint surface on the tunnel entrance side and the diagonal joint surfaces on both sides of the shaft in each hexagonal segment. These hexagonal segments are attached in advance, and by assembling them in succession in the axial and circumferential directions of the tunnel, the caulking material is applied to the inner peripheral surface of the tunnel of each joint surface of the adjacent hexagonal segments. Preferably, it is interposed between the edge portions and is sandwiched around the entire circumference of each hexagonal segment.

Furthermore, in the hexagonal segment joining structure of the present invention, a notch attachment portion is formed along the edge portion of each joining surface of the adjacent hexagonal segments on the tunnel inner peripheral surface side, and the caulking material is , it is preferable that the hexagonal segments are interposed between the notch attachment portions and sandwiched around the entire circumference of each hexagonal segment.

Furthermore, in the hexagonal segment joining structure of the present invention, the sealing material acts as a tunnel inner peripheral surface side sealing material and an outer peripheral surface side sealing material in a region between the caulking material and the buffer material. It is preferable that two strips are provided continuously over the entire circumference of the hexagonal segment.

According to the joint structure of hexagonal segments of the present invention, water inside the tunnel can be effectively prevented from leaking to the outside of the tunnel from the joints of adjacent hexagonal segments, and the joint surface of the hexagonal segments can be effectively prevented from leaking to the outside of the tunnel. It is possible to effectively avoid damage to the edge on the outer circumferential surface side.

FIG. 2 is a partially cutaway perspective view illustrating a lining body made up of a plurality of hexagonal segments joined via a hexagonal segment joining structure according to a preferred embodiment of the present invention. The configuration of a joining structure of hexagonal segments according to a preferred embodiment of the present invention will be explained. (a) is a cross-sectional view taken along AA or BB in FIG. 1, and (b) is a C in (a). (c) is an enlarged view of part D in (a). To explain the configuration of the hexagonal segment, (a) is a front view, (b) is a side view of (a) seen from direction E, (c) is a side view of (a) seen from direction F, and (d ) is a circumferential end view of (a) viewed from the G direction. (a) to (c) are explanatory views of the process of assembling a plurality of hexagonal segments to form a lining body.

A hexagonal segment joining structure 10 (see FIGS. 2(a) to 2(c)) according to a preferred embodiment of the present invention connects a plurality of hexagonal segments 12 in the axial direction ( When forming the lining body 11 that covers the inner circumferential surface of a shield tunnel for a reservoir that preferably temporarily stores rainwater by assembling it in a honeycomb shape in the excavation direction) X and the circumferential direction Y, It is used as a joining structure to join each adjacent hexagonal segment 12. The hexagonal segment joint structure 10 of the present embodiment can prevent water inside the tunnel from leaking to the outside of the tunnel from the joint 50 of adjacent hexagonal segments 12, and A function is provided to avoid damage to the edges of the outer peripheral surfaces of the joint surfaces 13, 14, 15, and 16.

As shown in FIGS. 1 to 3, the hexagonal segment joint structure 10 of the present embodiment has a face-side joint surface 13 and a mine-mouth side joint surface 14 arranged in parallel, and these joint surfaces 13, 14. A hexagonal shape comprising a pair of V-shaped circumferential joint surfaces 17 consisting of a face-side diagonal joint surface 15 and a wellhead-side diagonal joint surface 16, which are arranged in a V-shape so as to connect the ends on both sides of the shaft. When forming the shield tunnel lining 11 by assembling the segments 12 (see FIGS. 3(a) to 3(d)) in series in the axial direction X and circumferential direction Y of the tunnel (see FIG. 1) , a joint structure provided at a joint portion 50 of adjacent hexagonal segments 12, interposed between each joint surface 13, 14, 15, 16 of adjacent hexagonal segments 12, A sealing material 18 is continuously sandwiched around the entire circumference (see FIGS. 2(a) to 2(c)), and inside the tunnel of each joint surface 13, 14, 15, 16 of adjacent hexagonal segments. A caulking material 19 is interposed between the edge portions on the peripheral surface side and is sandwiched around the entire circumference of each hexagonal segment 12 (see FIGS. 2(a) and 2(b)). A cushioning material 20 is interposed between the edges of the outer peripheral surfaces of the joint surfaces 13, 14, 15, and 16 of the square segments 12, and is sandwiched around the entire circumference of each hexagonal segment 12 (see FIG. 2(a), (c)).

Further, in this embodiment, as shown in FIGS. 3(a) to 3(d), the buffer material 20 preferably includes the wellhead side joint surface 14 and the wellhead side diagonal joint surfaces 16 on both sides in each hexagonal segment 12. It is attached in advance to the edge of the outer circumferential surface. By assembling these hexagonal segments 12 in series in the axial direction It is interposed between the edge portions on the outer peripheral surface side of the hexagonal segments 15 and 16, and is sandwiched over the entire circumference of each hexagonal segment 12.

As shown in FIGS. 3(a) to 3(d), the caulking material 19 is also applied preferably to the tunnel inner circumferential surface of the tunnel entrance side joint surface 14 and both shaft entrance side diagonal joint surfaces 16 in each hexagonal segment 12. It is pre-attached to the edge of the By assembling these hexagonal segments 12 in series in the axial direction It is interposed between the edge portions 15 and 16 on the inner peripheral surface side of the tunnel, and is sandwiched over the entire circumference of each hexagonal segment 12.

In this embodiment, the lining body 11 made up of the hexagonal segments 12 shown in FIG. 1 preferably forms a tunnel with an inner diameter of about 6400 mm, as a shield tunnel for a reservoir that temporarily stores rainwater. It becomes. In addition, the lining body 11 has hexagonal segments 12, which will be described later, preferably made of concrete with an anti-corrosion layer on the inner surface and integrated with the secondary lining, so that the inner circumferential surface is smooth. By keeping it in this state, the inner circumferential surface can be used as it is as the inner circumferential surface of a tunnel through which rainwater flows.

As shown in FIGS. 3(a) to 3(d), each hexagonal segment 12 forming the lining body 11 is connected to a face-side joint surface 13 and a tunnel-side joint surface 14 that are arranged in parallel. A pair of V-shaped circumferential joint surfaces 17 consisting of a face-side diagonal joint surface 15 and a wellhead-side diagonal joint surface 16, which are arranged in a V-shape so as to connect the ends on both sides of the surfaces 13 and 14, respectively. The segment is made of reinforced concrete and has a hexagonal planar shape (see FIG. 3(a)). The hexagonal segment 12 has a thickness of, for example, about 600 mm, and a cross section along the face-side joint surface 13 and the wellhead-side joint surface 14 has a radius of curvature corresponding to the inner diameter of the lining body 11, for example, 6400 mm. , has an arcuate shape (see FIGS. 3(b) and 3(c)). The hexagonal segment 12 has a width of about 2000 mm between the face side joint surface 13 and the wellhead side joint surface 14, and a length of about 4000 mm between the tips of the pair of V-shaped circumferential joint surfaces 17. It is formed like this. The angle θ between the face side diagonal joint surface 15 and the wellhead side diagonal joint surface 16 in each V-shaped circumferential joint surface 17 is 120° (see FIG. 3(a)). Thereby, the plurality of hexagonal segments 12 are attached to the face-side diagonal joint surfaces 15 and 13 of the preceding hexagonal segments 12, and to the tunnel-side diagonal joint surfaces 16 and 13 of the hexagonal segments 12 to be installed subsequently. The well mouth side joint surfaces 14 can be arranged in a honeycomb shape in the axial direction and the circumferential direction in a state in which they are successively overlapped with each other (see FIG. 1).

In addition, in this embodiment, the face-side joint surface 13, the tunnel-side joint surface 14, the face-side diagonal joint surface 15, and the shaft-side diagonal joint surface 16 of each hexagonal segment 12 are shown in FIGS. 2 and 3(a). ) to (d), outer seal grooves 21a with a width of about 20 mm are continuously formed around the entire circumference at intervals of about 60 mm from the outer circumferential surface, and at intervals of about 60 mm from the inner circumferential surface. Inner seal grooves 21b having a width of about 20 mm are continuously formed at intervals of about 20 mm over the entire circumference. A sealing material 18, preferably made of a band-shaped water-swellable sealing material, is continuously attached to the outer seal groove 21a as the outer peripheral surface side sealing material 18a, for example, via an adhesive, over the entire circumference, Similarly, a sealing material 18 preferably made of a band-shaped water-swellable sealing material is continuously attached to the inner sealing groove 21b over the entire circumference, for example, via an adhesive, as the inner peripheral surface side sealing material 18b. ing. That is, in this embodiment, in the region between the caulking material 19 and the buffer material 20, which will be described later, the sealing material 18 is applied to each hexagonal segment as a tunnel inner peripheral surface side sealing material 18b and an outer peripheral surface side sealing material 18a. Two continuous strips are provided over the entire circumference of 12.

Furthermore, in this embodiment, each hexagonal segment 12 has an edge on the tunnel inner peripheral surface side on the face-side joint surface 13, the tunnel-side joint surface 14, the face-side diagonal joint surface 15, and the shaft-side diagonal joint surface 16. A notch mounting portion 22 having a width of approximately 30 mm is continuously formed along the entire circumference. A known band-shaped caulking material is used as the caulking material 19 in the notch attachment portion 22 formed in the three joint surfaces 14 and 16 of the wellhead side joint surface 14 and the pair of wellhead side diagonal joint surfaces 16, for example. Continuously attached via adhesive. As the band-shaped caulking material, for example, one having the same structure as the shield segment caulking material described in Japanese Patent No. 4,646,501 can be used. More specifically, the product name "Sea Coke" (manufactured by Sekisui Chemical Co., Ltd.) can be preferably used.

The caulking material 19 made of such a band-shaped caulking material is applied to the notch attachment portions facing each other at the joint portions 50 of adjacent hexagonal segments 12 when the plurality of hexagonal segments 12 are assembled to form the lining body 11. By being sandwiched in a compressed state or sandwiched in a state where it can absorb water and swell, it fills the joints without any gaps, and the water inside the tunnel prevents the joint from forming. It becomes possible to firmly prevent leakage from the portion 50 to the outside of the tunnel (see FIGS. 2(a) and 2(b)).

Further, the caulking material 19 is attached to a notch attachment portion 22 formed in the three joint surfaces 14 and 16, the joint surface on the wellhead side 14 and the pair of diagonal joint surfaces on the wellhead side 16. Since it is not attached to the notch mounting portion 22 of the surface 13 and the pair of face side diagonal joint surfaces 15, after the hexagonal segment 12 is assembled, the next hexagonal segment 12 following this on the face side is not attached. Until the caulking material 19 is assembled, it is possible to avoid the caulking material 19 being exposed and being damaged or broken during, for example, excavation work.

When the next succeeding hexagonal segment 12 on the face side is assembled to the notch attachment portions 22 of the face-side joint surface 13 and the pair of face-side diagonal joint surfaces 15 to which the caulking material 19 is not attached, By sandwiching the caulking material 19 attached to the notch attachment portion 22 of the wellhead-side joint surface 14 or the wellhead-side diagonal joint surface 16 of the hexagonal segment 12, the caulking material 19 is attached to each of the adjacent hexagonal segments 12. It is interposed between the edge portions of the joint surfaces 13, 14, 15, and 16 on the tunnel inner peripheral surface side, and is sandwiched over the entire circumference of each hexagonal segment 12.

Furthermore, in the present embodiment, a band-shaped buffer with a width of about 20 mm, for example, made of a known material is provided as a buffer material 20 on the wellhead-side joint surface 14 of each hexagonal segment 12 and the pair of wellhead-side diagonal joint surfaces 16. The material is continuously attached along the outer circumferential edge, for example via an adhesive. The cushioning material 20 has, for example, cushioning properties, flexibility, and lightness, and can be preferably formed using a foamed polyethylene sheet. More specifically, it is preferable to use the product name "Miramat (registered trademark)" (manufactured by JSP Co., Ltd.) by cutting it into a predetermined width and length.

The cushioning material 20 made of such a band-shaped cushioning material is arranged so that when a plurality of hexagonal segments 12 are assembled to form the lining body 11, each of the opposing joint surfaces at the joint portion 50 of the adjacent hexagonal segments 12 is It is sandwiched between the edge portions of the outer peripheral surfaces of 13, 14, 15, and 16 (see FIGS. 2(a) and 2(c)). The buffer material 20 is attached to the edge portions of the outer circumferential surfaces of the wellhead-side joint surface 14 and the pair of wellhead-side diagonal joint surfaces 16, and is not attached to the face-side joint surface 13 and the pair of face-side diagonal joint surfaces 15. Therefore, after the hexagonal segment 12 is assembled, the cushioning material 20 remains exposed until the next hexagonal segment 12 is assembled on the face side of the hexagonal segment 12, for example, during excavation work. It is possible to avoid damage or damage to the product. When the next succeeding hexagonal segment 12 is assembled to the face-side joint surface 13 and the pair of face-side diagonal joint surfaces 15 to which the cushioning material 20 is not attached, the wellhead-side joint of the next hexagonal segment 12 is attached. By sandwiching the cushioning material 20 attached to the surface 14 and the diagonal joint surface 16 on the wellhead side, the cushioning material 20 is attached to the edge of the outer peripheral surface of each joint surface 13 , 14 , 15 , 16 of the adjacent hexagonal segment 12 . It will be interposed between the sections and sandwiched around all 12 circumferences of each hexagonal segment.

In the present embodiment, each hexagonal segment 12 is further provided with a portion from a side region on both sides of the face-side joint surface 13, similar to the hexagonal segment (hexagonal segment) described in, for example, Japanese Patent No. 3253870. A diagonal bolt insertion hole 23 is provided toward the center of the diagonal joint surface 16 on the tunnel entrance side, extending parallel to and penetrating the diagonal joint surface 15 on the face side. At the end of each diagonal bolt insertion hole 23 on the face side joint surface 13 side, a fastening recess 23a for fastening the head of the connecting bolt member 24 (see FIG. 4(c)) is provided so that the opening surface is on the face side. It is formed with an opening in the joint surface 13. A positioning recess 13a is provided in a portion of the face side joint surface 13 closer to the face side diagonal joint surface 15 than each of the fastening recesses 23a. A pair of positioning protrusions 14a provided on the joint surface 14 on the tunnel entrance side of the hexagonal segment 12 installed subsequently in the tunnel excavation direction X are fitted into these positioning recesses 13a. It is installed. As a result, the entire wellhead side joint surface 14 of the subsequently installed hexagonal segment 12 is overlapped with the entire face side joint surface 13 of the previously installed hexagonal segment 12 with high precision. , adjacent hexagonal segments 12 in the tunnel excavation direction X can be positioned. That is, the wellhead side joint surface 14 of each hexagonal segment 12 is provided with positioning protrusions 14a in side regions on both sides thereof.

Further, in this embodiment, a female threaded hole 15a is provided in the center of the pair of face-side diagonal joint surfaces 15 of each hexagonal segment 12 by, for example, embedding a female threaded anchor. . The female screw hole 15a is formed when the face-side diagonal joint surface 15 of the previously installed hexagonal segment 12 is superimposed on the tunnel face-side diagonal joint surface 16 of the hexagonal segment 12 installed subsequently. The bolt insertion hole 23 provided in the hexagonal segment 12 communicates linearly with an end portion of the bolt insertion hole 23 on the side opposite to the fastening recess 23a. As a result, by inserting and tightening the connecting bolt member 24 through the communicating bolt insertion hole 23 and female threaded hole 15a, each adjacent hexagonal segment 12 arranged in a honeycomb shape is firmly integrated into one body. It becomes possible to connect them (see FIG. 4(c)).

Furthermore, in this embodiment, similarly to the hexagonal segment (hexagonal segment) described in, for example, Japanese Patent No. 3253870, the face-side diagonal joint surface 15 and the tunnel-side diagonal joint surface 16 of each hexagonal segment 12 are , a guide protrusion 25a and a guide recess 25b for positioning are provided, respectively. These positioning guide convex portions 25a and guide concave portions 25b are used when installing the next hexagonal segment 12 following the previously installed hexagonal segment 12. By locking the guide recess 25b and the guide protrusion 25a so as to be slidable in the installation direction, the hexagonal segments 12 installed in advance protrude forward in the excavation direction X at intervals in the circumferential direction Y. The following hexagonal segments 12 are guided to be placed in the respective intervals between each pair of isosceles trapezoidal portions (see FIG. 4(a)), so that accurate positioning is possible. , has a function of preventing the assembled hexagonal segments 12 from being misaligned.

Furthermore, in this embodiment, each hexagonal segment 12 is provided with a gripping hole 26, for example on the inner surface, which allows the hexagonal segment 12 to be gripped by an assembly erector device (not shown). A pair of lifting insert fittings 27 are provided in the central portion and are arranged, for example, in side regions on both sides of the wellhead side joint surface 14, and are capable of lifting the hexagonal segment 12.

Preferably, a plurality of hexagonal segments 12 having the above-mentioned configuration are arranged in series in the axial direction (excavation direction) In order to form the lining 11 that covers the inner peripheral surface of the shield tunnel, for example, as shown in FIGS. The face-side joint surface 13 and the face-side diagonal joint surface 15 of the square segment 12 are joined to the tunnel entrance-side joint surface 14 and the tunnel entrance-side diagonal joint surface 16 of the hexagonal segment 12 that are subsequently assembled on the front side in the excavation direction X of the tunnel. A plurality of hexagonal segments 12 are formed into a tunnel by overlapping each other and alternately protruding the isosceles trapezoidal portions of each hexagonal segment 12, which are the front half portions in the tunnel excavation direction X. They are arranged in a honeycomb shape in the axial direction X and the circumferential direction Y, and are sequentially assembled.

Furthermore, when a plurality of hexagonal segments 12 are sequentially assembled in the axial direction The shield jack 60 is pressed against the face-side joint surface 13 at the tip of the isosceles trapezoidal part divided into two parts in the excavation direction X, and while the shield excavator excavates while taking the reaction force, Then, the subsequent hexagonal segment 12 is assembled in the region between the adjacent isosceles trapezoidal portions against which the shield jack 60 is pressed.

That is, in the region between adjacent isosceles trapezoidal parts where the shield jack 60 is pressed against the face side joint surface 13, as shown in FIG. Then, the isosceles trapezoidal part of the rear half of the hexagonal segment 12 to be assembled subsequently is inserted into the isosceles trapezoidal interval part in the area between them, and the joint surface 14 on the tunnel entrance side and the tunnel entrance are inserted. The side diagonal joint surfaces 16 are brought into close contact with the face side joint surfaces 13 and the face side diagonal joint surfaces 15 of the previously assembled hexagonal segments 12 (see FIG. 4(b)). After that, for example, among the three shield jacks 60 arranged in the area between the adjacent isosceles trapezoidal parts, the central one shield jack 60 is extended to lead the subsequent hexagonal segment 12. As shown in FIG. 4(c), the bolt insertion hole 23 of the succeeding hexagonal segment 12 and the hexagonal segment 12 installed previously are pressed against the assembled hexagonal segment 12. These hexagonal segments 12 are connected together by inserting and tightening the connecting bolt member 24 into the female screw hole 15a.

These operations are performed in each region between adjacent protruding isosceles trapezoidal portions formed in the circumferential direction, and the hexagonal segments 12 newly installed in this way are As the existing hexagonal segments 12 are assembled, the shield jack 26 is pressed against these face-side joint surfaces 13 to remove the reaction force while the shield excavator excavates, and in parallel with this, the shield jack 26 is pushed. By repeating the process of assembling subsequent hexagonal segments in the area between these hexagonal segments 12, a plurality of hexagons arranged in a honeycomb shape in the axial direction X and circumferential direction Y of the tunnel are formed. By using the segments 12, it is possible to easily form a lining 11 that preferably covers the inner peripheral surface of a shield tunnel for a reservoir for temporarily storing rainwater.

According to the hexagonal segment joint structure 10 of the present embodiment having the above-described configuration, leakage of water inside the tunnel to the outside of the tunnel from the joint portion 50 of the adjacent hexagonal segments 12 can be effectively prevented. In addition, the outer peripheral surfaces of the respective joint surfaces 13, 14, 15, and 16 by the face-side joint surface 13, well-mouth-side joint surface 14, face-side diagonal joint surface 15, and shaft-side diagonal joint surface 16 of the hexagonal segment 12 can be prevented. It is possible to effectively avoid damage to the side edges.

That is, according to the hexagonal segment joining structure 10 of the present embodiment, the entire circumference of each hexagonal segment 12 is interposed between the joining surfaces 13, 14, 15, 16 of adjacent hexagonal segments 12. Preferably two strips of sealing material 18 are continuously sandwiched between (see FIGS. 2(a) to (c)), and each joint surface 13, 14, 15, 16 of the adjacent hexagonal segment A caulking material 19 is interposed between the edge portions on the inner peripheral surface side of the tunnel, and is sandwiched over the entire circumference of each hexagonal segment 12 (see FIGS. 2(a) and 2(b)), and A cushioning material 20 is interposed between the edge portions on the outer peripheral surface side of each joint surface 13, 14, 15, 16 of adjacent hexagonal segments 12, and is sandwiched over the entire circumference of each hexagonal segment 12. (See Figures 2(a) and (c)).

According to the present embodiment, the hexagonal segments interposed between the joint surfaces 13, 14, 15, and 16 prevent groundwater from entering the tunnel from the ground around the tunnel. The sealing material 18 that is continuously sandwiched around the entire circumference of the tunnel can effectively prevent the water flowing inside the tunnel from leaking to the outside of the tunnel. This can be effectively prevented by the caulking material 19 interposed between the edge portions of the joint surfaces 13, 14, 15, and 16 on the tunnel inner peripheral surface side and sandwiched around the entire circumference of each hexagonal segment 12. In particular, at the V-shaped circumferential joint surface 17, the compressed caulking material and the expanded caulking material sandwiched between the edges of the joint surfaces 13, 14, 15, and 16 on the tunnel inner peripheral surface side can be removed. Even if a reaction force is applied by the deformable caulking material to spread out the edge on the inner peripheral surface side of the tunnel, the action of these reaction forces is absorbed by the outer periphery of each joint surface 13, 14, 15, 16. The joint surfaces 13, 14, 15 of the hexagonal segment 12 are absorbed by the cushioning material 20 sandwiched between the edge portions of the hexagonal segments 12, thereby preventing excessive unbalanced loads from being applied to the edge portions of the outer peripheral surface. , 16 on the outer peripheral surface side can be effectively prevented from being damaged.

Note that the present invention is not limited to the above-described embodiments, and various changes can be made. For example, the sealing material does not necessarily need to be provided in two strips in the area between the caulking material and the cushioning material, and may be provided in only one strip. The cushioning material does not necessarily need to be formed using a foamed polyethylene sheet, and can be formed using various other sheet materials having cushioning properties.

10 Joint structure of hexagonal segments 11 Lining body 12 Hexagonal segment 13 Face side joint surface 13a Positioning recess 14 Well mouth side joint surface 14a Positioning convex part 15 Face side diagonal joint surface 15a Female screw hole 16 Well mouth side diagonal Joint surface 17 V-shaped circumferential joint surface 18 Sealing material 18a Outer peripheral surface side sealing material 18b Inner peripheral surface side sealing material 19 Caulking material 20 Cushioning material 21a Outer seal groove 21b Inner seal groove 22 Notch mounting portion 23 Diagonal bolt insertion hole 23a Fastening recess 24 Connection bolt member 25a Positioning guide convex 25b Positioning guide recess 26 Gripping hole 27 Lifting insert 50 Joint 60 Shield jack X Tunnel excavation direction (axial direction)
Y Circumferential direction of tunnel

Claims (5)

The face-side joint surface and the wellhead-side joint surface are arranged in parallel, and the face-side diagonal joint surface and the mine-mouth side diagonal joint are arranged in a V-shape so as to connect the ends on both sides of these joint surfaces, respectively. When forming a shield tunnel lining by assembling hexagonal segments each having a pair of V-shaped circumferential joining surfaces in the axial and circumferential directions of the tunnel, the adjacent hexagonal segments A joint structure of hexagonal segments provided at a joint of square segments,
A sealing material is interposed between each joint surface of adjacent hexagonal segments and is continuously sandwiched around the entire circumference of each hexagonal segment, and a tunnel of each joint surface of adjacent hexagonal segments is provided. A caulking material is interposed between the edge portions on the inner peripheral surface side and is sandwiched around the entire circumference of each hexagonal segment in a compressed state or in a state capable of absorbing moisture and swelling, and It is interposed between the edge portions on the outer peripheral surface side of each joint surface of adjacent hexagonal segments so that the edge portions on the inner peripheral surface side of the tunnel are expanded by the caulking material in a compressed state or in an expandable and deformable state. When a reaction force is applied, a cushioning material that absorbs the action of these reaction forces is sandwiched around the entire circumference of each hexagonal segment,
A joint structure of hexagonal segments, wherein the sealing material is continuously provided over the entire circumference of each hexagonal segment in a region between the caulking material and the buffering material. In each hexagonal segment, the buffer material is attached in advance to the outer peripheral surface side edge portion of the joint surface on the tunnel entrance side and the diagonal joint surfaces on both sides of the shaft, and these hexagonal segments are aligned with the axis of the tunnel. By being assembled in a continuous manner in the direction and circumferential direction, the buffer material is interposed between the edge portions on the outer peripheral surface side of each joint surface of adjacent hexagonal segments, and covers the entire hexagonal segment. The hexagonal segment joining structure according to claim 1, wherein the hexagonal segments are sandwiched around the circumference. In each hexagonal segment, the caulking material is attached in advance to the tunnel inner peripheral surface side edge portions of the joint surface on the tunnel entrance side and the diagonal joint surfaces on both sides of the shaft, and these hexagonal segments The caulking material is interposed between the edge portions of the joint surfaces of the adjacent hexagonal segments on the tunnel inner peripheral surface side, and is attached to each hexagonal segment. 3. The hexagonal segment joining structure according to claim 1 or 2, wherein the hexagonal segments are sandwiched over the entire circumference of the segment. A notch attachment portion is formed along the edge portion of each joint surface of the adjacent hexagonal segments on the inner peripheral surface side of the tunnel, and the caulking material is interposed between these notch attachment portions. 4. The hexagonal segment joining structure according to claim 1, wherein the hexagonal segments are sandwiched around the entire circumference of each hexagonal segment. The sealing material is formed in two continuous strips around the entire circumference of each hexagonal segment as a sealing material on the inner peripheral surface of the tunnel and a sealing material on the outer peripheral surface in the region between the caulking material and the buffer material. A joining structure of hexagonal segments according to any one of claims 1 to 4, wherein the hexagonal segment joining structure is provided.

Images