JP2013083120A - Composite segment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent exfoliation by efficiently suppressing out-of-plane deformation of a bank-side steel plate and an inner-side steel plate of a segment and to reduce manufacturing costs.SOLUTION: A composite segment 1 is provided in which, on surfaces of skin plates 2A and 2B opposed to concrete 3, a plurality of L-shaped steel materials 6 and a plurality of dowels 7 are provided. The plurality of L-shaped steel materials 6 extend in a tunnel axial direction X and are arrayed in a tunnel circumferential direction Y and integrated with the skin plates 2A and 2B while protruding to the side of the concrete 3. Between the neighboring L-shaped steel materials 6 and 6 and between joint plates 5A and 5B and the L-shaped steel material 6, the dowels 7 are arrayed in the tunnel circumferential direction Y while protruding to the side of the concrete 3, provided in a plurality of lines in the tunnel axial direction X and integrated with the skin plates 2A and 2B. An arrangement interval of the neighboring L-shaped steel materials 6 and 6 is narrower than a segment width and regarding the dowels 7, an arrangement interval in the tunnel axial direction X is larger than an arrangement interval in the tunnel circumferential direction Y.

Description

  The present invention has a skin plate on at least one of a natural ground side and an inner air side of a tunnel, is formed in an arc plate shape filled with concrete inside, and is connected in a plurality in the circumferential direction and the axial direction of the tunnel. It is related with the synthetic segment which comprises a cylindrical wall body by this.

Conventionally, in a shield method of forming a tunnel by excavating a drill hole in a natural ground and constructing a cylindrical wall body by connecting a plurality of arc-shaped segments on the inner surface in the circumferential direction and the axial direction, A synthetic segment manufactured by filling concrete in a circular arc frame (steel shell) is known. In a composite segment with such a curvature and having a skin plate (steel plate) on either or both of the natural ground side and the interior sky side, the steel plate on the natural ground side will be In addition, since the steel plate on the inner air side peels off on the inner air side, the integrity with the concrete cannot be maintained. That is, this peeling makes it difficult for compressive force and tensile force to act on the steel sheet, and the proof stress and rigidity as a synthetic segment are reduced.
Therefore, in order to increase the effective cross-section of the natural steel plate and the inner steel plate by suppressing the separation and integrating the steel plate and concrete constituting the steel shell, it prevents slippage on the surface of the steel plate facing the concrete. The structure which provides a member is employ | adopted (for example, refer patent document 1, 2).

The synthetic segment described in Patent Document 1 includes a plurality of gibbers that are fixed by protruding from each of the steel skin plates provided on the ground surface side and the inner air side of the tunnel to the opposite skin plate side. (Slip prevention member).
According to Patent Document 2, a shear plate is provided with a displacement between a skin plate disposed on a natural ground side or an inner space side and concrete, and the peeling of the steel material is suppressed by a fixing material (a detent member). A configuration that can reduce the determined number of fixing materials is disclosed.

JP 2007-270485 A JP 2011-12490 A

However, in order to increase the effective cross section of the natural steel plate and the inner steel plate, the conventional synthetic segment that prevents the separation by providing a slip prevention member has the following problems.
That is, in the synthetic segment of Patent Document 1, since the number of dowels is determined according to the shear deviation between the skin plate and the concrete, there is a problem that the necessary number of dowels increases and the manufacturing cost for processing increases. . Moreover, in the synthetic segment of patent document 2, since peeling of a steel plate shows the peeling property of two directions, in order to suppress peeling efficiently, there exists a fault that the number of fixing materials will increase.
As described above, in the prior art, the number of processing steps such as welding of the non-slip member to the steel plate and correction of welding deformation and the manufacturing cost for these increase, and there is room for improvement in that respect.

  The present invention has been made in view of the above-described problems, and can effectively prevent out-of-plane deformation of the ground-side steel plate and the inner-side steel plate of the segment to prevent peeling, thereby reducing the manufacturing cost. An object is to provide a composite segment that can be achieved.

  In order to achieve the above object, in the composite segment according to the present invention, at least two main girders and two joint plates arranged at both ends in the circumferential direction of the tunnel and joined so as to pass between the main girders; The steel plate provided on at least one of the natural mountain side and the inner air side, and a synthetic segment having a curvature formed by filling concrete inside the steel shell, the surface of the steel plate facing the concrete, A plurality of linear members integrated in the steel plate by being arranged in the tunnel circumferential direction in a state of extending in the tunnel axis direction and protruding toward the concrete side, between adjacent linear members, and between the joint plate and the linear member Are arranged in the circumferential direction of the tunnel in a state of protruding toward the concrete side, and a plurality of rows are provided in the direction of the tunnel axis, and are provided with point-like members integrated with the steel plate. Arrangement interval of the linear members together to fit the smaller than the segment width, point-like member is characterized by arrangement interval between the tunnel axis is larger than the arrangement interval of the tunnel circumferential direction.

  In the synthetic segment according to the present invention, the surface pressure applied to the steel plate by earth water pressure can be reliably transmitted to the main beam. Specifically, by arranging the spacing between adjacent linear members so as to be narrower than the segment width, at least the buckling strength of the steel plate in the tunnel circumferential direction is reduced in the tunnel axial direction, that is, in the segment width direction. It becomes possible to make it larger than the proof stress. Therefore, it is possible to prevent the segment from being buckled by receiving an axial force in the in-plane direction, and the integrity of the steel plate and the concrete of the segment from being impaired. That is, the steel plate is buckled first along the circumferential direction of the tunnel, and the proof stress of the entire segment cannot be effectively exhibited by reducing the proof stress of the entire segment before flowing the load from the earth water pressure to the main girder. Trouble can be eliminated.

  And since the main cause of the out-of-plane deformation of the steel sheet is caused by the force of the radial component of the axial force in the tunnel circumferential direction, the surface in the tunnel circumferential direction can be effectively arranged by densely arranging the linear members in the tunnel circumferential direction. External deformation can be prevented. Therefore, also in the number of point-like members, by arranging the point-like members in the tunnel circumferential direction more densely than the tunnel axial direction, the out-of-plane deformation of the steel plate can be efficiently suppressed, Yield strength and rigidity can be effectively increased.

Moreover, by arranging a plurality of linear members in the circumferential direction of the tunnel, it is possible to reduce the amount of initial irregularity in production that leads to the peeling of the steel sheet, to reduce the amount of peeling from the concrete, and to improve the integrity with the internal concrete. .
Furthermore, by combining linear members extending along the tunnel axis direction and point-like members arranged in the tunnel circumferential direction, the segments are vertically placed so that the tunnel axis direction is in the vertical direction during segment manufacture. Since the linear members are arranged in a state where the longitudinal direction of the linear members is directed in the vertical direction, it is possible to improve the filling property of the concrete and to manufacture high quality segments.

Moreover, by arranging the linear member and the dotted member only on the steel plate on the inner space side, it becomes possible to expect the suppression effect due to earth water pressure against the out-of-plane deformation of the steel plate on the natural ground side, and efficiently The effect of suppressing the out-of-plane deformation of the steel sheet can be enhanced.
Further, in the point-like members, the point-like members are arranged in an appropriate quantity that can be significantly reduced by arranging the point-like members so that the arrangement interval in the tunnel axis direction is larger than the arrangement interval in the tunnel circumferential direction. be able to.

  Moreover, in the synthetic segment which concerns on this invention, it is preferable that a dotted | punctate member becomes staggered arrangement | positioning along a tunnel axial direction.

  With such a configuration, the point-shaped members are arranged so that the cone breaking lines do not overlap, so that the fixing strength of the point-shaped members can be efficiently ensured.

  Moreover, in the synthetic segment which concerns on this invention, it is preferable that several dot-shaped members are arrange | positioned densely in the center part of a segment axial direction.

  In this case, by arranging the point-like members in the central portion in the segment axial direction where a large load is applied, the number of the point-like members can be reduced and the out-of-plane deformation of the steel sheet can be efficiently suppressed. . In other words, since the out-of-plane deformation of the steel sheet can be continuously suppressed at the position of the main beam, a plurality of discretely arranged point-like members are efficiently arranged densely in the middle part in the segment axial direction. It is possible to suppress the out-of-plane deformation of the steel plate and ensure the effective width of the steel plate.

  Moreover, in the synthetic segment which concerns on this invention, it is preferable that a linear member is a perforated steel plate.

  With such a configuration, by using a perforated steel sheet for the linear member arranged in the tunnel axial direction, this hole becomes a concrete passage during production, and the concrete filling property can be improved. It is possible to prevent air accumulation inside. Therefore, the integration of the concrete with the linear member or the point-like member can be achieved, and the quality can be improved.

  In the synthetic segment according to the present invention, the linear member may be a T-shaped steel plate.

  In this case, by using a T-shaped steel plate in a cross-sectional view for the linear member extending along the tunnel axis direction, it is possible to increase the cone fracture area compared to an L-shaped member such as angle steel. It is possible to increase the pulling strength of the linear member and reduce the member specifications.

  According to the synthetic segment of the present invention, the linear member and the dot-like member are suitably combined and arranged to effectively suppress the out-of-plane deformation of the ground-side steel plate and the inner air-side steel plate of the segment and prevent peeling. can do. Therefore, it is possible to increase the design effective cross section of the steel sheet without increasing the steel materials such as the main girder and the connecting rib, and it is possible to reduce the number of point-like members and to reduce the manufacturing cost.

FIG. 2 is a partially broken perspective view showing a configuration of a synthetic segment according to the first embodiment of the present invention. It is the sectional view on the AA line shown in FIG. It is the BB sectional view taken on the line shown in FIG. It is a top view which shows the functional area | region of a panel with 4 sides fixed. It is sectional drawing of the synthetic | combination segment by 2nd Embodiment, Comprising: It is a figure corresponding to FIG. It is a figure which shows arrangement | positioning of the dotted | punctate member in the synthetic | combination segment by 3rd Embodiment. It is a figure which shows the perforated steel plate by a 1st modification, Comprising: (a) is a side view, (b) is CC sectional view taken on the line shown to (a). It is a figure which shows the T-shaped steel plate by a 2nd modification, Comprising: (a) is a sectional side view, (b) is a side view. It is sectional drawing of the synthetic | combination segment by a 3rd modification, Comprising: It is a figure corresponding to FIG.

  Hereinafter, the synthetic segment by embodiment of this invention is demonstrated based on drawing.

(First embodiment)
As shown in FIG. 1, the composite segment 1 according to the first embodiment forms a tunnel lining body constructed on an inner wall excavated by a shield method, for example. A pair of skin plates 2A, 2B (steel plates) formed to be curved in an arcuate plane are respectively arranged in parallel facing a position on the ground mountain side and a position on the inner sky side of the tunnel, and the skin plate Concrete 3 is filled between 2A and 2B, and it is comprised by the substantially circular arc board shape.

  As shown in FIGS. 1 to 3, the natural skin side skin plate 2A and the inner skin side skin plate 2B have two long sides (tunnels) along the circumferential direction Y of the two skin plates 2A and 2B. Arc-shaped main girders 4A and 4B are provided to connect the two ends (in the axial direction X) to each other, and the two short sides (the two ends in the tunnel circumferential direction Y) along each tunnel axis direction X are connected in a straight line. Joint plates 5A and 5B are provided. The main girders 4A and 4B are provided with a plurality of bolt holes 4a for connecting segments adjacent to each other in the tunnel axis direction X, respectively. The joint plates 5A and 5B are provided with a plurality of bolt holes 5a for connecting segments adjacent in the tunnel circumferential direction Y to each other.

  Furthermore, seal grooves (not shown) are formed on the outer surfaces (surfaces exposed to the outside) of the main girders 4A and 4B and the joint plates 5A and 5B along the respective sides of the skin plates 2A and 2B. The seal material is fitted into the seal groove.

  Each of the skin plates 2A and 2B has a plurality of (four in FIG. 2 and FIG. 3) L-shaped steel members 6 (linear members) extending in the tunnel circumferential direction Y extending on the inner surfaces facing each other in the tunnel axis direction X. A plurality of stud dowels (hereinafter simply referred to as “jivel 7”) provided at predetermined intervals and further protruding and fixed to the skin plates 2A and 2B facing the head 7a (see FIG. 1) by a predetermined length (see FIG. 1). A point-like member) is provided.

  The L-shaped steel material 6 has both ends in the length direction fixed to the inner surfaces of the main girders 4A and 4B, and one L-shaped end plate 6a is fixed to the inner surfaces of the skin plates 2A and 2B by welding or the like. The one end plate 6a is substantially perpendicular to the skin plates 2A and 2B, and the other end plate 6b is disposed in a state in which the surface direction of the other end plate 6b faces the tunnel circumferential direction Y. And the arrangement | positioning space | interval of adjacent L-shaped steel materials 6 and 6 is narrower than the segment width.

  The bevel 7 is arranged in the tunnel circumferential direction Y in a state of protruding to the concrete 3 side between the adjacent L-shaped steel materials 6 and 6 and between the L-shaped steel material 6 and the joint plates 5A and 5B. An array group is provided in a plurality of rows at predetermined intervals in the tunnel axis direction X, and is provided integrally with each skin plate 2A, 2B. The gibber 7 is integrated with the close contact with the filled concrete 3. Further, the arrangement distance of the tunnel 7 in the tunnel axis direction X is larger than the arrangement distance in the tunnel circumferential direction Y.

The gibber 7 is provided with three rows of rows arranged along the tunnel circumferential direction Y in the composite segment 1.
Here, an arrangement interval between the divels 7 and 7 arranged in the tunnel circumferential direction Y is defined as a circumferential interval D1, and an interval between the dowels 7 and 7 arranged in the tunnel axial direction X is defined as an axial interval D2. In the present embodiment, the arrangement interval between the gibber 7 and the main girders 4A (4B) is also equal to the axial interval D2.

  Further, the arrangement intervals of the divels 7 are preferably arranged at a pitch of 0.08 or more and less than 1.0, which is a value obtained by dividing the circumferential interval D1 by the axial interval D2 (hereinafter referred to as “diver arrangement ratio”). .

  The circumferential interval D1 and the axial interval D2 (the minimum center interval between the adjacent divels 7 and 7) of the divel 7 are 5d (d: the radial dimension mm of the dibel) or 100 mm. This is described in “Road Bridge Specification / Common Commentary / Steel Bridge”, March 2002, Japan Road Association, page 335, 11.5.4 Minimum Stoppage (3). This is based on the description that “the minimum center distance of the stud in the bridge axis direction is 5 d or 100 mm”.

  The reason why the arrangement ratio of the dowels is less than 1.0 is that when the number of dowels is 1.0 or more, the necessary number of dowels is the same as the case where the shear displacement force is suppressed only by the conventional dowels (stud dowels), and the number of dowels increases. It is because it ends up.

Moreover, the reason why the above-mentioned dowel arrangement ratio is set to 0.08 or more is as follows.
That is, when the maximum segment width (length dimension in the tunnel axis direction X) is about 2400 mm due to the limitation of the vehicle width of a truck or the like that transports the segment width, The direction interval D2 is 1200 mm. This 1200 mm is the maximum value of the axial distance D2. And since the minimum center space | interval of the adjacent jibels 7 and 7 will be 5d or 100 mm as mentioned above, a bridge axis direction will correspond to the circumferential direction space | interval D1. Therefore, a value obtained by dividing the minimum distance 100 mm by 1200 mm, which is the maximum value of the axial distance D2, is 0.08, and this 0.08 is the minimum value.

Next, the effect | action of the synthetic | combination segment 1 comprised as mentioned above is demonstrated based on drawing.
As shown in FIGS. 1 to 4, in this synthetic segment 1, the surface pressure received by the skin plates 2 </ b> A and 2 </ b> B by the soil water pressure can be reliably transmitted to the main girders 4 </ b> A and 4 </ b> B. Specifically, the buckling strength of at least the skin plates 2A and 2B in the circumferential direction Y of the tunnel is set in the tunnel axial direction by arranging the arrangement intervals between the adjacent L-shaped steel materials 6 and 6 to be narrower than the segment width. X, that is, larger than the buckling strength in the segment width direction can be maintained.
Therefore, it is possible to prevent the composite segment 1 from receiving axial force in the in-plane direction and causing the skin plates 2A and 2B to buckle and the integrity of the skin plates 2A and 2B and the concrete 3 from being impaired. That is, the skin plates 2A and 2B are buckled first along the circumferential direction Y of the tunnel, and the proof strength of the entire segment is reduced before the load from the soil water pressure flows to the main girders 4A and 4B. It is possible to eliminate such a problem that it cannot be made effective.

Thus, in order to effectively use the entire members, at least the buckling strength of the skin plates 2A and 2B in the tunnel circumferential direction Y is set larger than the buckling strength in the tunnel axial direction X (segment width direction). There is a need.
Here, the buckling of the skin plates 2A and 2B is evaluated by the Euler formula. As shown in FIG. 4, the arrangement interval between adjacent L-shaped steel materials 6 and 6 is a, the segment width is b, and the skin plates 2A and 2B between the L-shaped steel materials 6 and 6 in the segment circumferential direction Y (FIG. 3). the buckling strength _{sigma cra} of), the main girder 4A segment axis X, skin plate 2A between 4B, the buckling strength of 2B was _{sigma crb.}

  The boundary conditions are expressed at all ends in the direction in which the axial force acts, because the welding conditions between the skin plates 2A and 2B and the main girders 4A and 4B and the L-shaped steel material 6 are appropriately set and changed. In order to make this possible, the buckling coefficient is k, and the welding conditions between the skin plates 2A, 2B and the main girders 4A, 4B and the L-shaped steel 6 are appropriately set on the side surface parallel to the direction in which the axial force acts. In order to change, it was set as the free condition which is the most dangerous side for buckling of the skin plates 2A and 2B.

In order to delay buckling in the segment circumferential direction Y from the segment width direction X under these conditions, the axial force in the tunnel circumferential direction Y tends to be superior to the axial force in the segment width direction X due to the influence of the load condition. However, at least the expression (1) needs to be satisfied. In the equation (1), σ _cra and σ _crb are described by the equations (2) and (3), respectively. Then, when the expressions (2) and (3) are substituted into the expression (1), the expression (4) is obtained. Therefore, it turns out that the arrangement | positioning space | interval b of adjacent L-shaped steel materials 6 and 6 needs to be made smaller than the segment width | variety a.

  Thus, since the main cause of the out-of-plane deformation of the skin plates 2A and 2B is caused by the force of the radial component of the axial force in the tunnel circumferential direction Y, the L-shaped steel material 6 is densely arranged in the tunnel circumferential direction Y. Thus, the out-of-plane deformation in the tunnel circumferential direction Y can be effectively prevented. Therefore, also in the number of the jibels 7, the out-of-plane deformation of the skin plates 2A and 2B can be efficiently suppressed by arranging the jibels 7 in the tunnel circumferential direction Y more densely than the tunnel axis direction X. The yield strength and rigidity as the synthetic segment 1 can be effectively increased.

  Two main girders 4A and 4B and a pair of adjacent L-shaped steel members 6 extending in the tunnel axis direction X in the natural and inner skin plates 2A and 2B on which the L-shaped steel members 6 are integrally provided. 4, the region P in which the four sides are fixed (the region surrounded by the thick dotted line in FIG. 4) functions as a panel with four sides fixed, so that the out-of-plane deformation of the skin plates 2 </ b> A and 2 </ b> B can be suppressed. It is possible to increase the yield strength and rigidity of the composite segment 1. And since the arrangement | positioning space | interval of the tunnel circumferential direction Y of adjacent L-shaped steel materials 6 and 6 is narrower than a segment width | variety, the suppression effect of an out-of-plane deformation can further be improved.

  Further, since the gibber 7 is disposed between the main girders 4A and 4B and the L-shaped steel material 6, the adhesion with the concrete 3 is increased, and the peeling between the concrete 3 and the skin plates 2A and 2B is suppressed. The effect of suppressing out-of-plane deformation can be further improved.

Further, by arranging a plurality of L-shaped steel materials 6, 6,... In the tunnel circumferential direction Y, the initial irregularity in production leading to the peeling of the skin plates 2 </ b> A, 2 </ b> B is reduced, and the peeling amount for the concrete 3 is reduced. The integrity with the internal concrete 3 can be enhanced.
Further, by combining the L-shaped steel material 6 extending along the tunnel axis direction X and the dowels 7 arranged in the tunnel circumferential direction Y, the composite axis is set so that the tunnel axis direction X becomes the vertical direction when the segment is manufactured. When placing 1 vertically, since the longitudinal direction of the L-shaped steel material 6 is arranged in the vertical direction, it becomes possible to improve the filling property of the concrete 3, and the high quality synthetic segment 1 Can be produced.

  Further, in the jebel 7, the arrangement is made so that the arrangement interval in the tunnel axial direction X is larger than the arrangement interval in the tunnel circumferential direction Y, so that the divel 7 is arranged in an appropriate quantity that can be greatly reduced. be able to.

  Moreover, in the diver 7, the diver 7 is significantly reduced by arranging the diver 7 so that the value obtained by dividing the circumferential interval D1 by the axial interval D2 (gibel arrangement ratio) is 0.08 or more and less than 1.0. It can be arranged in the proper quantity possible. In particular, when the ratio is the smallest, the number of dowels 7 can be minimized when the effective width of the set skin plates 2A and 2B is secured.

For example, although different from the arrangement of the present embodiment shown in FIGS. 1 to 3 (arrangement of linear members and dotted members), the segment width is 1500 mm, the thickness of the skin plate is 19 mm, and the curvature radius is When the distance between linear members such as L-shaped steel materials as in this embodiment is about 6000 mm and 800 mm, when the conventional shear displacement force is suppressed only by the stud gibber, The circumferential distance D1 is 150 mm, the axial distance D2 is 150 mm, the circumferential distance D1 / the axial distance D2 is 1.0, and the required number of stud dowels is 189 per skin plate.
Further, the arrangement interval of the stud divels is 200 mm in the circumferential interval D1, 250 mm in the axial interval D2, the circumferential interval D1 / the axial interval D2 can be set to 0.8, and the necessary number of stud divels is skin. There will be 90 per plate. Therefore, the number of stud gibbles in the present embodiment is approximately half that of the prior art.

  Further, the L-shaped steel material 6 has a shape in which the protruding tip projects toward the tunnel circumferential direction Y, and since the cross-sectional shape of the protruding tip is larger than that of the base end portion of the gibber 7, the adhesion force to the concrete 3 is increased. In addition, since more reliable integration can be achieved, the peeling prevention effect can be improved.

Furthermore, the synthetic segment 1 of the present embodiment has an advantage that it is easy to manufacture and can reduce the manufacturing cost because it is not a structure reinforced by vertical ribs as in the prior art. That is, in the synthetic segment 1 according to the present embodiment, in the case of a six-sided steel shell, it is difficult to weld the vertical rib to the skin plate on the inner space side or the natural mountain side, and thereby the skin plate of the vertical rib portion. And the conventional configuration such that the effective width (rigidity) of the skin plate is reduced can be eliminated.
Moreover, in this synthetic segment 1, when the vertical rib is not subjected to anticorrosion coating with a five-sided steel shell having a skin plate on the natural ground side, the concrete covering thickness is required, and the concrete must be raised. Therefore, it is possible to eliminate the problem of the conventional configuration that the material cost of concrete increases.

  In the synthetic segment according to the first embodiment described above, the out-of-plane deformation of the skin plates 2A and 2B on the natural ground side and the inner air side of the segment 3 is achieved by suitably arranging the L-shaped steel material 6 and the diver 7 in combination. Can be efficiently suppressed to prevent peeling. Therefore, it is possible to increase the design effective cross section of the skin plates 2A and 2B without increasing the steel materials such as the main girders 4A and 4B and the connecting ribs, and it is possible to reduce the number of the gibber 7 and reduce the manufacturing cost. Can be achieved.

  Next, another embodiment of the composite segment of the present invention will be described with reference to the accompanying drawings. The same reference numerals are used for the same or similar members and parts as those in the first embodiment described above. A configuration different from that of the first embodiment will be described.

(Second Embodiment)
The synthetic segment 1A according to the second embodiment shown in FIG. 5 has a staggered arrangement of dowels 7 (dot-like members) along the tunnel axis direction X.
In this case, since the construction is such that the dowel 7 is arranged so that the cone breaking lines do not overlap, the fixing strength of the dowel 7 can be efficiently ensured.

(Third embodiment)
The composite segment 1B of the third embodiment shown in FIG. 6 includes a plurality of dowels 7, 7,... (That is, the array group 7A, 7B, 7C of the dowels 7 arranged in the tunnel circumferential direction Y). It is densely arranged in the center of the direction X.
In this case, the arrangement number of the gibber 7 can be reduced by arranging the gibber 7 in the central portion in the segment axial direction X where a large load is applied, and the out-of-plane deformation of the skin plates 2A and 2B is efficiently suppressed. be able to. In other words, since the out-of-plane deformation of the skin plates 2A and 2B can be continuously suppressed at the positions of the main girders 4A and 4B, the plurality of discretely arranged dowels 7 are densely arranged at the central portion in the segment axial direction X. By arranging, the out-of-plane deformation of the skin plates 2A and 2B can be efficiently suppressed, and the effective width of the skin plates 2A and 2B can be secured.

(First modification)
In the first modification shown in FIGS. 7A and 7B, a perforated steel plate 8 (linear member) is employed instead of the L-shaped steel material 6 (see FIG. 1) of the above-described embodiment. is there.
With such a configuration, by using the perforated steel plate 8 arranged in the tunnel axial direction, the hole 8a becomes a passage for the concrete 3 (see FIG. 1) at the time of manufacture, and the concrete filling property can be improved. It is possible to prevent air accumulation in the steel shell of the segment. Therefore, it is possible to integrate the concrete 3 with the perforated steel plate 8 or the gibber 7 and improve the quality.

(Second modification)
In the second modification shown in FIGS. 8A and 8B, a T-shaped steel plate 9 (linear member) is adopted instead of the L-shaped steel material 6 (see FIG. 1) of the above-described embodiment. It is. In the T-shaped steel plate 9, the base end portion 9b is fixed to the skin plates 2A and 2B by welding or the like so that the protruding portion 9a is on the inner side of the segment.
In this case, by using a T-shaped steel plate in a cross-sectional view for the linear member extending along the tunnel axis direction X, the cone fracture area can be increased as compared with the L-shaped member described above. Therefore, the pulling strength of the T-shaped steel plate 9 can be increased, and the member specifications can be reduced.

As mentioned above, although the embodiment of the synthetic segment by this invention was described, this invention is not limited to said embodiment, It can change suitably in the range which does not deviate from the meaning.
For example, in the above-described embodiment, three rows of the jbells 7 are arranged in the tunnel axis direction X. However, the number of rows and intervals of the jibles 7 are not limited to this, and depending on the shape and size of the segment. It is possible to set. For example, as shown in the composite segment 1C shown in FIG. Also in this case, for example, the diver 7 can be arranged such that a value (ratio) obtained by dividing the circumferential interval D1 of the diver 7 by the axial interval D2 is 0.08 or more and less than 1.0.

  In the above-described embodiment, the composite plate in which the skin plates 2A and 2B forming the steel plate are provided on the ground mountain side and the sky side in the tunnel is targeted. However, the present invention is not limited to this. For example, by disposing the L-shaped steel material 6 and the gibber 7 only on the skin plate 2B on the inner space side, it is possible to expect the effect of suppressing the out-of-plane deformation of the steel plate on the natural mountain side by soil water pressure, In particular, the effect of suppressing the out-of-plane deformation of the steel sheet can be enhanced.

  Furthermore, in the present embodiment, the L-shaped steel material 6, the perforated steel plate 8, and the T-shaped steel plate 9 are adopted as the linear members, but the present invention is not limited to this, and linear members having other cross-sectional shapes such as a plate shape. May be used. And although the gibber 7 is employ | adopted as a dotted | punctate member, not only this but a volt | bolt, a pin, etc. can also be used. Specifically, the male screw portion of the bolt is screwed into a bottomed or through screw hole formed in each skin plate 2A, 2B, and a pin having a large-diameter head is connected to the skin plate 2A, 2B. It is possible to adopt a configuration in which a bottomed hole or a through-hole that is smaller than a shaft portion of a pin provided in the press-fit is configured, or a configuration having other appropriate configurations. Further, in the present embodiment, the linear member is installed to suppress peeling in the out-of-plane direction of the skin plate, but it is possible to rationally form a cross section by considering it as a detent stop. Become.

  In addition, it is possible to appropriately replace the components in the above-described embodiments with known components without departing from the spirit of the present invention.

1, 1A, 1B, 1C Composite segment 2A, 2B Skin plate (steel plate)
3 Concrete 4A, 4B Main girder 5A, 5B Joint plate 6 L-shaped steel (Linear member)
7 Giber (dot-like member)
8 Perforated steel sheet (linear member)
9 T-shaped steel plate (linear member)
D1 Circumferential distance D2 Axial distance X Tunnel axial direction Y Tunnel circumferential direction

Claims (5)

At least two main girders, two joint plates arranged at both ends in the circumferential direction of the tunnel and joined so as to pass between the main girders, and a steel plate provided on at least one of the natural ground side and the inner air side And a synthetic segment having a curvature formed by filling concrete inside a steel shell having:
On the surface of the steel plate facing the concrete,
A linear member that extends in the tunnel axis direction and is arranged in the tunnel circumferential direction in a state of protruding toward the concrete side and integrated with the steel plate,
Between the adjacent linear members, and between the joint plate and the linear member, it is arranged in the tunnel circumferential direction in a state of protruding toward the concrete side, and a plurality of rows are provided in the tunnel axial direction. A point-like member integrated with the steel plate;
Is provided,
An arrangement interval between adjacent linear members is narrower than a segment width, and the dot-like member has an arrangement interval in the tunnel axis direction larger than an arrangement interval in the tunnel circumferential direction.   The synthetic segment according to claim 1, wherein the point-like members are staggered along the tunnel axis direction.   The composite segment according to claim 1, wherein the plurality of point-like members are densely arranged at a central portion in a segment axial direction.   The synthetic segment according to any one of claims 1 to 3, wherein the linear member is a perforated steel plate.   The said linear member is a T-shaped steel plate, The synthetic segment of any one of Claims 1 thru | or 4 characterized by the above-mentioned.

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