JP5217330B2 - Simple synthesis segment - Google Patents

Description

  The present invention relates to a synthetic segment formed by filling a concrete shell into a steel shell having vertical ribs, and more particularly to a simple synthetic segment that has a simpler synthetic structure and a cheaper synthetic segment.

  Conventionally, a synthetic segment 1A as shown in FIG. 14 is known. The composite segment 1A has a plurality of structures in parallel to the main girder 3 in the longitudinal direction of the main girder 3 inside the steel shell 2 provided with the main girder 3, the joint plate 4, the skin plate 5, and the longitudinal rib 6. The vertical rib 6 is fixed.

  Then, a bar-shaped steel material 7 is arranged in the tunnel circumferential direction over the outer side of each vertical rib 6, and a composite structure in which the inside-filled concrete 8 is filled and solidified inside the segment so as to embed the vertical rib 6 and the bar-shaped steel material 7 is synthesized. This is segment 1A.

  Such a combined segment 1A is installed at a predetermined position in the ground to construct a tunnel by segment ring. When earth and water pressure P (for example, see the design load P in FIG. 13) from the natural ground side acts on such a tunnel, a secondary bending moment that causes the filling concrete 8 to come out acts, The concrete 8 protrudes to the inner side of the tunnel and is separated as shown by a two-dot chain line in FIG.

  In this case, the steel shell 2 and the filling concrete 8 cannot be integrated, and the filling force of the filling concrete 8 cannot bear the compressive force in the tunnel circumferential direction. Suddenly drops.

  Normally, in the composite segment 1A, the compressive force in the tunnel circumferential direction is borne by the filling concrete, the tensile force in the tunnel circumferential direction is borne by the steel shell 2 such as the main girder, and the jack thrust in the tunnel axial direction is given by the longitudinal rib 6 Alternatively, it is borne by the filling concrete 8.

Since the vertical ribs 6 are arranged at an angular interval in the tunnel radial direction, even if the vertical ribs 6 are plate-like vertical ribs 6 directed toward the center in the tunnel radial direction, the vertical ribs 6 adjacent to each other in the tunnel circumferential direction are adjacent to each other. The inside concrete 8 is supported in a wedge shape by the ribs 6 so as to narrow toward the tunnel center side, but the angle between the adjacent vertical ribs 6 and the tunnel center is 30 degrees or more. It is not a wedge angle but a small angle of about 10 to 20 degrees.
The angle between the joint plate 4, the tunnel center and the longitudinal rib 6 is also a small angle as described above. Therefore, the filling concrete 8 between the adjacent vertical ribs 6 is not firmly supported by the adjacent vertical ribs 6. Similarly, the filling concrete 8 between the joint plate 4 and the vertical rib 6 is not firmly supported by the joint plate 4 and the vertical rib 6 as well.
Even if there is a wedge angle as described above, the adjacent vertical ribs 6 or the joint plates 4 and the vertical ribs 6 in the segment become nearly parallel as the tunnel radius increases, and the vertical angle depends on the wedge angle. The supporting action of the filling concrete 8 using the rib 6 or the joint plate 4 is reduced.

  The following is also known as means for preventing the state in which the steel shell 2 and the filling concrete 8 are separated as described above.

  That is, a structure is known in which a large number of displacement stoppers are arranged on the inner surface side of the main girder in order to synthesize the main girder and filling concrete (for example, see Patent Documents 1 and 2).

  As described above, in order to achieve a synthetic integration of the steel shells constituting the segments and the concrete filled in the steel shells, a number of slip stoppers are provided at intervals on the steel shell side. It is generally known to do.

  As a method of providing the above-mentioned displacement prevention, a number of displacement preventions are provided at intervals in each structural material such as a main girder or a joint plate or a longitudinal rib which is a structural material in the tunnel circumferential direction or tunnel axial direction in the steel shell. I am trying to provide it.

  As described above, the composite segment provided with a large number of displacement stoppers has a structure in which the steel shell and the filled concrete are firmly integrated.

  If a large number of slip stoppers are provided for each structural material constituting the segment as described above, it takes a lot of time for the welding work and the like, and a high degree of skill is required, and the construction is complicated, and synthesis is required. There is a problem that the cost of the segment is a factor.

JP 2002-38888 (Synthetic segment) JP-A-8-296398 (steel segment)

  Also, the main girder has a cross-sectional groove shape, L-shaped cross section or H-shaped cross section, and a flange is arranged on the inner side of the tunnel in the main girder, and the flange protrudes into the inner side of the tunnel inside the tunnel. However, if such a main girder has a cross-sectional groove shape, an L shape, or a H shape, the cost of the main girder is significantly increased, and there is a problem that the composite segment becomes expensive.

Filled concrete supported by the vertical ribs arranged between the main girders in the composite segment is subjected to a secondary bending that maximizes the center position of the vertical rib intervals unless a stopper is provided.
Therefore, a larger acting force is generated in the concrete than the main girder, causing a decrease in proof stress.

  The inventor of the present invention pays attention to a technique in which a plurality of or a large number of displacement stoppers are arranged between the longitudinal ribs in the tunnel circumferential direction arranged between the main girders, and the longitudinal ribs in the tunnel circumferential direction as such. Various investigations were made on the necessity of providing a plurality of or a large number of detents between them.

  When it is possible to suppress the secondary bending of filling concrete while minimizing the slippage prevention on the inner side of the main girder, it is possible to produce a synthetic segment at low cost while combining the segment steel shell and concrete. I found out that it would be possible.

  In addition, in the form of providing a plurality of slip stoppers between the vertical ribs, it takes time and cost for manufacturing. Further, it has been found that even if a pair or one stopper is provided between the longitudinal ribs, it is possible to combine the segment steel shell and the concrete. Accordingly, it is necessary to provide a stopper 9 at least at an intermediate portion between the longitudinal ribs 6 in the circumferential direction of the tunnel so as to achieve simple synthesis and integration through the stopper 9 between the filling concrete 8 and the steel shell 2.

  As described above, the present invention is an inexpensive synthetic segment with a simple structure, while ensuring sufficient strength as a segment, while simply integrating and integrating the steel shell segment and the concrete filled therein. The purpose is to provide.

In order to solve the above-mentioned problem advantageously, in the simple composite segment of the first invention, the main girder in the steel-based segment having the main girder, the joint plate, the skin plate, and the vertical rib is arranged in the length of the main girder in the segment. A plurality of vertical ribs are fixed at intervals in the direction, rod-shaped steel materials are arranged in the tunnel circumferential direction across the tunnel inner air side of each vertical rib, and are arranged at intervals in the tunnel circumferential direction in the segments. At least at the center between the longitudinal ribs, a pair of detents are provided on the main girders facing each other at an interval so as to protrude toward the facing surface side of these main girders . The projecting length is such that it reaches the rod-shaped steel material disposed closest to the main girder, and the angled portion is made of angle steel provided so that the groove portion faces the skin plate side. Is characterized in that the middle packed concrete have been synthesized integrally filled and solidified in the internal segment so as to fill the longitudinal ribs and the rod-like steel as well as displacement-preventing.
Further, in the second invention, in the simple composite segment of the first invention, the slip stopper is provided so as to be positioned closer to the inner surface of the tunnel than the rod-shaped steel material in the tunnel circumferential direction, and is embedded in concrete. And
According to a third invention, in the simple composite segment of the first invention or the second invention, the bar-shaped steel material is a reinforcing bar.
According to a fourth aspect of the present invention, in the simple synthetic segment according to any one of the first to third aspects, the main girder is a plate steel material.

According to the present invention, the following effects can be obtained.
(1) At least in the middle part between the longitudinal ribs in the circumferential direction of the tunnel, a slip stopper is provided so as to protrude toward the main girder, or a slip stopper is provided across the main girder and only embedded in the filling concrete. Thus, an effect can be obtained in which a simple synthetic segment in which the steel shell, the steel bar in the circumferential direction, and the filled concrete are simply integrated can be obtained.
(2) Since there is no need to provide a large number of displacement stoppers, it is only necessary to provide a displacement stopper only at an approximately middle position between adjacent vertical ribs in the circumferential direction of the tunnel. Easy to manufacture, inexpensive and simple synthetic segments.
(3) Even if soil pressure acts on the composite segment from the natural ground side, since it is equipped with a slip stopper, secondary bending (bending toward the sky inside the tunnel) of filled concrete can be suppressed. It is possible to improve the safety of the tunnel structure by suppressing the secondary bending of concrete filled concrete.
(4) Since the secondary bending of the filled concrete is suppressed by slippage, the crack width of the filled concrete can be reduced, and the tunnel durability is improved by reducing the crack width of the filled concrete. be able to.
(5) When the main girder is connected to the main girder, the main girder between the longitudinal ribs can be reinforced, and moreover, it is possible to more reliably prevent the filling concrete from sticking out. Can be integrated with filled concrete.
(6) When the stopper is arranged between the main girders so as to be located in the inner radial side of the tunnel in the radial direction of the tunnel than the rod-shaped steel in the circumferential direction of the tunnel, It can be restrained so as not to move.
(7) A simple synthetic segment that uses reinforcing steel as the bar-shaped steel in the circumferential direction of the tunnel and plate steel as the main girder. It can be.
(8) If it is a simple synthetic segment that uses angle steel as a detent and plate steel as the main girder, use a commercially available inexpensive steel material to make it a cheaper and simpler synthetic segment. Can do. In this case, if a reinforcing bar is used as the rod-shaped steel material in the circumferential direction of the tunnel, it is possible to make a simple synthetic segment that is much cheaper and simpler.

    Next, the present invention will be described in detail based on the illustrated embodiment.

  1 to 3 show a simple synthetic segment 1 according to the first embodiment of the present invention. The steel shell 2 is made of a steel plate extending in the circumferential direction of the tunnel, and a pair of arc-shaped main girders 3 and a joint plate made of steel plate arranged over the ends of these main girders 3 and fixed integrally by welding or the like 4, a steel skin plate 5 on the natural ground side fixed by welding to these, and a parallel arrangement at intervals in the tunnel circumferential direction in the main girder 3 and arranged so as to span the tunnel axis direction, It comprises a plurality of vertical ribs 6 fixed to the main girder 3 by welding.

  Moreover, the rod-shaped steel material 7 of the tunnel circumferential direction is arrange | positioned so that it may bridge | cross the tunnel circumferential direction over each vertical rib 6 so that it may be located in the tunnel inner space side rather than each vertical rib 6 in the said steel shell 2. Yes.

  In the form shown in the figure, a rod-shaped steel material 7 in the circumferential direction of the tunnel made of a plurality of (5 in the illustrated example) deformed reinforcing bars parallel to the tunnel axis direction is placed on the vertical rib 6 and filled in the segment. It is embedded and fixed in the filling concrete 8.

Then, only in the middle part (preferably only one of the central positions) between the adjacent vertical ribs 6 spaced in the circumferential direction of the tunnel, the main girders 3 facing each other with a distance in the tunnel axis direction. A pair of short stoppers 9 are arranged so as to protrude toward the opposing surface side of these main girders 3, and the base end sides of the respective stoppers 9 are fixed to the main girders 3 by welding.
Similarly, only in the middle part (preferably one place at the substantially central position) between the joint plate 4 and the longitudinal rib 6 adjacent in the tunnel circumferential direction, the main girders 3 facing each other with an interval in the tunnel axis direction are provided. A pair of short stoppers 9 are provided so as to protrude toward the opposing surface side of these main girders 3, and each of the stoppers 9 is embedded in the filling concrete 8.
For example, as shown in FIG. 2, the protruding length of the shift stopper 9 may be such that it reaches the rod-shaped steel material 7 in the circumferential direction of the tunnel disposed at a position closest to the main girder 3. Since each of the displacement stoppers 9 is supported by the main girder 3 in a cantilever manner, it is not preferable to increase the length because bending stress acts greatly.
In addition, when the dimension between the joint plate 4 and the vertical rib 6 is a small dimension (for example, a narrow interval of 1/2 or less of the dimension between the adjacent vertical ribs 4, and it is possible to prevent the stuffed concrete 8 from protruding. ), The stopper 9 may be omitted. Therefore, it is necessary to provide a stopper 9 at least in the center between the longitudinal ribs 6 in the circumferential direction of the tunnel so as to achieve a simple synthetic integration through the stopper 9 between the filling concrete 8 and the steel shell 2.

The slip stopper 9 is made of a shape steel such as an equilateral angle steel 9A, and one end of the equilateral angle steel 9A is fixed to the side surface of the main girder 3 in the steel shell 2 by welding. The arrangement position of the stopper 9 in the tunnel radial direction is a position away from the skin plate 5 toward the inner space of the tunnel, and is preferably disposed so as to be located near the center of the height of the segment or more toward the inner space. Is done. In addition to the equilateral angle steel 9 </ b> A, the misalignment stopper 9 can be made of other shape steel or steel materials such as reinforcing bars and deformed steel bars.
Since the grooves in the equilateral angle steel 9A as the stopper 9 are arranged so as to face the skin plate 5 side, it is possible to reliably and reliably support the inside concrete 8 on the ground mountain side from each side of the equilateral angle steel 9A. . For this reason, it is possible to reliably prevent the inside-filled concrete 8 from protruding due to earth water pressure P from the natural ground side.
The vertical rib 4, the rod-shaped steel material 7, and the respective stoppers 9 are embedded in the filling concrete 8, and the rod-shaped steel material 7 is embedded and fixed in the filling concrete 8, so The stuffed concrete 8 is fixed integrally to form a simple composite segment 1.

  The surface of the stopper 9 or the vertical rib 6 is roughened, or a recess or a through-hole is provided on the surface of the stopper 9 or the vertical rib 6 to make the solid concrete 7 stronger. And may be integrated.

  In the embodiment shown in the drawing, the stopper 9 is disposed so as to be located closer to the ground (outside) in the tunnel radial direction than the rod-shaped steel material 7 in the tunnel circumferential direction. It is not preferable that the above-described displacement stopper 9 is disposed so as to be positioned closer to the inner space of the tunnel than the rod-shaped steel material 7 in the circumferential direction of the tunnel, and the cover thickness of the filling concrete 8 with respect to the displacement stopper 9 is reduced.

  In the present invention, as shown below, by simply placing the rod-shaped steel material 7 in the circumferential direction of the tunnel on the vertical rib 6, not only the production of the simple composite segment 1 is facilitated, but also the production cost is reduced. It can be made cheap.

  In the case of manufacturing the simple synthetic segment 1, after manufacturing the steel shell 2 to which the stopper 9 is attached, the inner rib side is turned up, and the vertical rib 6 is bent to a predetermined curvature over the tunnel inner space side. The rod-shaped steel material 7 in the circumferential direction of the tunnel is placed, and if necessary, temporarily fixed with a binding wire or the like in order to prevent displacement of the rod-shaped steel materials 7 in the circumferential direction of the tunnel.

  In order to prevent displacement of the rod-shaped steel members 7 in the circumferential direction of the tunnel when concrete is filled in the steel shell 2 with the inner concave portion of the steel shell 2 facing upward, the assembly rebar is arranged so that the tunnel is arranged. You may make it position each rod-shaped steel material 7 of the circumferential direction.

As described above, the filling concrete 8 is filled and solidified in a state where the stopper 9 and the rod-shaped steel material 7 in the circumferential direction of the tunnel are arranged at predetermined positions, and the steel shell 2 and the filling concrete 8 are integrated. As shown.
In the state in which the filling concrete 8 is hardened, the slipping prevention 9 prevents the filling concrete 8 from sticking out. Therefore, even if the rod-shaped steel material 7 is merely placed on the vertical rib 6, the rod-shaped steel material 7 Is held at a predetermined position placed on the vertical rib 6. Further, as described above, since the rod-shaped steel material 7 is held at a predetermined position, the steel material 7 resists compression or tension in cooperation with the filling concrete 8. Therefore, compared with the case of the conventional synthetic | combination segment which is not equipped with the slip stopper 9, the yield strength as a synthetic | combination segment can be improved.

  It should be noted that each rod-shaped steel material 7 in the tunnel circumferential direction is provided so as to be inserted into each vertical rib 6 or a mode in which the rod-shaped steel material 7 is inserted into each vertical rib 6 and fixed by welding or the like is a process of segments. Since the cost increases, the simple synthetic segment 1 can be manufactured at a lower cost by arranging the vertical rib 6 on the air side in the tunnel as described above.

  As in the above-described embodiment, a steel-based segment including a pair of main girders 3 made of a steel plate, a joint plate 4, a skin plate 5, a vertical rib 6 and a rod-like steel material 7 is provided between the vertical ribs 6 in the tunnel circumferential direction. With the stopper 9 provided on the main girder 3 at the part, the filling concrete 8 is filled and solidified. Thus, simply integrating the steel shell 2 side and the inside-filled concrete 8 makes it possible to obtain the simple composite segment 1 that is simply combined and integrated to prevent the inside-filled concrete 8 from protruding.

  In addition to the steel plate-like vertical rib 6, the vertical rib 6 may be a vertical rib having an L-shaped cross section, but it is cheaper to use a flat steel plate as described above. Simple synthetic segment 1 can be obtained.

  Although not shown in the drawings, as described in the paragraph 0015, the main girder has a cross-sectional groove shape, a cross-sectional L shape, or a cross-sectional H shape. Since the cost of this is significantly higher, the synthetic segment becomes expensive. However, as in the above-described embodiment shown in the drawing, the inside concrete 8 is filled and solidified in the steel shell 2 in a form that does not have a protruding flange projecting into the segment on the inner surface of the segment in the main girder 3. When the synthetic segment is manufactured so as to embed the rod-like member 7, it is easy and inexpensive to provide a stopper 9 as described above and to make a simple synthetic integration of the steel shell 2 and the filled concrete 8. A simple composite segment 1 can be configured.

  In the simple synthetic segment 1 configured as described above, when the earth and water pressure P is applied from the natural mountain side, the middle ribs 6 are filled between the vertical ribs 6 by the stoppers 9 disposed substantially at the center between the vertical ribs 6. The stuffed concrete 8 is prevented from protruding into the air in the tunnel, and the strength of the simple composite segment 1 is prevented from being lowered.

  The main girder 3 may be provided with a stopper 9 as in the present invention in a cross-section plate-shaped main girder or a steel shell that does not have a flange protruding inside the steel shell.

  There is only one pair of the stoppers 9 in the tunnel circumferential direction between the vertical ribs 6 so as to face each other, for example, as in the above embodiment, but in the vicinity of the center between the vertical ribs 6 in the tunnel circumferential direction. There may be a plurality of locations such as two in the circumferential direction of the tunnel. However, since it is not economical, it is preferable to use a single location as much as possible (the same applies to the embodiments described later).

  FIGS. 4-6 shows the simple synthetic | combination segment 1 of 2nd Embodiment of this invention, Comprising: In this form, in the intermediate part between the longitudinal ribs 6 in a tunnel circumferential direction, over the main girder 3, Both ends of a stopper 9 made of a single long angle steel are fixed to each main girder 3 by welding. In addition, at the intermediate portion between the joint plate 4 and the longitudinal rib 6 in the circumferential direction of the tunnel, both end portions of the shift stopper 9 made of a single long angle steel are joined to the main girders 3 by welding. It is fixed by welding. It arrange | positions so that the peak part in the slip stopper 9 which consists of the said angle steel may be located in the inner space side of a tunnel radial direction.

In such a configuration, since the main girders 3 are connected by the stoppers 9, the main girders 3 between the longitudinal ribs 6 can be reinforced and more reliably prevent the inside-filled concrete 8 from protruding. It is possible to integrate the steel shell 2 and the filled concrete 8 more reliably.
Instead of the stopper 9 made of the angle steel, the stopper 9 of a rod-shaped steel material such as a steel bar having a rectangular cross section may be used. Since other configurations are the same as those of the above-described embodiment, the same reference numerals are given to the same portions.

  7 to 9 show a simplified composite segment 1 according to a third embodiment of the present invention. In this embodiment, a stopper 9 made of deformed reinforcing bars is provided between the plate-like main girders 3. It is a form.

In this embodiment, the stopper 9 is arranged between the main girders 3 so as to be located on the inner side of the tunnel radial direction with respect to the rod-shaped steel material 7 in the tunnel circumferential direction, and both ends of the stopper 9 are connected to the main girders 3. It is fixed to the inner side surface of the segment by welding, and is a displacement stopper 9 that restrains the rod-shaped steel material 7 in the tunnel circumferential direction so as not to move toward the inner radial side in the tunnel radial direction.
In the case of such a configuration, after disposing the rod-shaped steel material 7 in the circumferential direction of the tunnel, the stopper 9 is disposed on the inner side of the tunnel so as to be placed on the rod-shaped steel material 7, and both ends of each stopper 9 The portions may be fixed to the main girder 3 by welding.
As in this form, the neutral axis in the tunnel circumferential direction in the composite segment 1 is prevented by the amount of the displacement stopper 9 disposed so as to be located on the inner side of the tunnel radial direction from the rod-shaped steel material 7 in the tunnel circumferential direction. Compared with the case where there is no 9, there is a position closer to the inner side of the tunnel. Therefore, when the bending of the composite segment protruding toward the inner space of the tunnel is effected by the earth and water pressure P from the natural ground side, the tensile region located on the inner space side of the synthetic segment with the neutral axis as a boundary is small. As a result, the compression area increases, which is advantageous.

  Further, in the illustrated form, for example, the displacement stopper 9 is made of a deformed reinforcing bar having a diameter (D) of 25 mm, and a commercially available inexpensive deformed reinforcing bar can be used. Therefore, the inexpensive simple synthetic segment 1 can be obtained. In addition, you may make it use the rod-shaped steel material of a cross-sectional rectangle shape as the said slip stopper 9. FIG.

  When carrying out the present invention, a simple synthetic segment 1 using a reinforcing bar as the rod-shaped steel material 7 in the tunnel circumferential direction, using an angle steel as the detent 9, and using a plate steel as the main girder 3 If it exists, it can be set as the cheap simple synthetic segment using a commercially available cheap steel material.

  Next, the simplified composite segment 1 of the third embodiment of the present invention provided with the detent 9 made of deformed reinforcing bars of the form shown in FIGS. 7 to 9 and shown in FIG. 14 without such detent 9. The result of comparing the synthesized segment 1A by numerical analysis will be described.

  FIG. 10 is an explanatory diagram showing numerically analyzed portions of the simple composite segment 1 of the present invention and the composite segment 1A of the comparative example, and only the ½ portion in the tunnel circumferential direction in each segment and the tunnel axis direction FIG. 7 is a partial schematic perspective view showing the size of each part in the part, which is the object of numerical analysis with respect to the area of the ¼ part as a whole segment in only ½ part.

  FIG. 11 is a perspective view for explaining a finite element method analysis showing a state in which the filling concrete 8 is removed from the synthetic segment 1A of the comparative example shown in FIG. 14 at a quarter portion of the segment shown in FIG.

  12 illustrates a finite element method analysis showing a state in which the filling concrete 8 in the simplified composite segment 1 of the third embodiment of the present invention shown in FIG. 7 is removed at a quarter portion of the segment shown in FIG. It is a perspective view for doing. In this numerical analysis, in order to clarify the effect, it is assumed that the stopper 9 is provided only at one position of the center line position A in the tunnel circumferential direction of the segment 1A. In addition, in the present invention, there is a slip stopper between the joint plate 4 and the longitudinal rib 6 and between the longitudinal ribs in addition to this one place.

  FIG. 14 is a schematic view of the first synthetic segment 1 according to the third embodiment of the present invention and, as a comparative example, the synthetic segment 1A when the stopper 9 is not provided. It is a perspective view which shows the form which adds a load to the tunnel circumferential direction other end side.

The dimensions of the main parts of the simple synthetic segment 1 of the present invention and the synthetic segment 1A as a comparative example are as follows.
The segment width is 650 mm, the main girder height is 86 mm, the thickness t of the steel plate of the skin plate 5 is 3 mm, the thickness t6 mm of the vertical rib 6, and the thickness t of the main girder 3 is 9 mm.
A case was assumed in which 7.5 kN was applied as a design load from the tunnel ground side to a tunnel outer diameter of 3.3 m composed of segments.
As shown in Fig. 13, the ½ portion of the tunnel circumferential direction and the ¼ portion of the ½ portion of the tunnel axial direction are used as a fulcrum so as to support the joint plate side. A three-point bending situation with the design load P (7.5 kN) added is shown. And synthetic segment 1 and synthetic segment 1A were analyzed.

  The measurement point of the simple composite segment 1 of the present invention shown in FIG. 12 is that the main girder 3 is in the tunnel radial direction inner space side, at the position A of the tunnel circumferential direction cut end, and in the tunnel circumferential direction indicated by the arrow A1. In addition to analyzing the elongation, the elongation in the tunnel circumferential direction indicated by the arrow B1 at the position B on the cut end side in the tunnel circumferential direction in the rod-shaped steel material 7 made of reinforcing bars in the tunnel circumferential direction was analyzed.

  The composite segment 1A of the comparative example is also the same as the measurement position of the composite segment 1 of the present invention described above, and the main girder 3 is at the inner space side in the tunnel radial direction and at the position A of the tunnel circumferential cut end. The elongation in the tunnel circumferential direction indicated by the arrow A1 was analyzed, and the elongation in the tunnel circumferential direction indicated by the arrow B1 was analyzed at the position B on the cut end side in the tunnel circumferential direction of the rod-shaped steel material in the tunnel circumferential direction.

  The analysis results and the elongation of the main girder 3 and the circumferential steel bar 7 made of steel bars are compared, and the results are shown in Table 1.

  As shown in Table 1, in the case of the simple composite segment 1 of the present invention provided with the stopper 9, compared to the composite segment 1A of the comparative example without the stopper, the main girder 3 and the circumferential reinforcing bars (circumferential bars) ) Is small. In this way, it can be seen that the main girder 3 and the reinforcing bars in the circumferential direction are less strained, and the load is averaged in the segment width direction including the intermediate concrete 8. Moreover, in the case of the simple composite segment 1 of the present invention of the above embodiment, it can be seen that the burden ratio between the main girder 3 and the rod-shaped steel material 7 in the tunnel circumferential direction is close, and the burden is evenly distributed in the width direction.

  As shown in the illustrated embodiment, the pair of main girders 3, the joint plate 4 and the longitudinal ribs 6 which are spaced apart from each other are flat steel plates, and the inside shell concrete 2 is filled with solidified concrete 8 and solidified. Then, it can be set as the simple synthetic | combination segment which combined the vertical rib 6 and the filling concrete 8 in the steel-type segment through the stopper 9 very reasonably.

The simple synthetic segment of 1st Embodiment of this invention is shown, Comprising: (a) is a vertical side view, (b) is the sectional view on the AA line of (a), (c) is B of (a). FIG. It is sectional drawing which expands and shows FIG.1 (c). It is the see-through | perspective perspective view which abbreviate | omitted the filling concrete and skin plate in the simple synthetic | combination segment of 1st Embodiment of this invention shown in FIG. 1, and was seen from the natural ground side. The simplified synthetic segment of 2nd Embodiment of this invention is shown, Comprising: (a) is a vertical side view, (b) is CC sectional view taken on the line (a), (c) is D of (a). FIG. It is sectional drawing which expands and shows FIG.4 (c). It is the see-through | perspective perspective view which abbreviate | omitted the filling concrete and skin plate in the simple synthetic | combination segment of 2nd Embodiment of this invention shown in FIG. 4, and was seen from the natural ground side. The simplified synthetic segment of 3rd Embodiment of this invention is shown, Comprising: (a) is a vertical side view, (b) is the EE sectional view taken on the line (a), (c) is F of (a). FIG. It is sectional drawing which expands and shows FIG.7 (c). It is the see-through | perspective perspective view which abbreviate | omitted the filling concrete and skin plate in the simple synthetic | combination segment of 3rd Embodiment of this invention shown in FIG. 7, and was seen from the natural ground side. It is a perspective view which shows the dimension for carrying out the numerical analysis of the synthetic | combination segment. It is explanatory drawing which shows the dimension and measurement position of a synthetic | combination segment which are not equipped with the slip stopper. It is explanatory drawing which shows the dimension and measurement position of the synthetic | combination segment of this invention provided with the slip stopper. It is explanatory drawing which shows the state to which the load of a segment is added. The synthetic segment of the conventional or comparative example is shown, Comprising: (a) is a longitudinal side view, (b) is an AA line sectional view of (a), (c) is a BB line section of (a). FIG.

Explanation of symbols

1 Simple composite segment 1
1A Composite segment 2 Steel shell 3 Main girder 4 Joint plate 5 Skin plate 6 Vertical rib 7 Bar-shaped steel 8 in the circumferential direction of the tunnel 8 Filled concrete 9 Detent 9A Equilateral steel

Claims (4)

A plurality of vertical ribs are fixed to the main girder in the steel-based segment having a main girder, a joint plate, a skin plate, and vertical ribs at intervals in the main girder longitudinal direction in the segment. Each of the main girders opposed to each other at intervals in at least the central portion between the longitudinal ribs arranged at intervals in the tunnel circumferential direction in the segment, in which rod-shaped steel materials are arranged in the tunnel circumferential direction over the inner space side Further, a pair of detents are provided so as to project toward the opposing surface side of these main girders, and the detents are projected so as to reach the rod-shaped steel material disposed at a position closest to the main girders. together has a length, consists of angle iron groove is provided so as to face the skin plate side, segment so as to fill the longitudinal ribs and the rod-like steel as well as displacement-preventing Simple synthetic segments, wherein the medium filled concrete are integrally synthesized filled and solidified therein and.   2. The simple composite segment according to claim 1, wherein the stopper is provided so as to be positioned closer to the inner surface of the tunnel than the rod-shaped steel material in the circumferential direction of the tunnel and embedded in concrete.   The simple synthetic segment according to claim 1 or 2, wherein the bar-shaped steel material is a reinforcing bar.   The simple synthetic segment according to any one of claims 1 to 3, wherein the main girder is a plate-shaped steel material.