JP4070566B2 - Tunnel block continuous construction method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a continuous construction method of a tunnel block, and more particularly to a continuous construction method of a tunnel block that efficiently constructs a tunnel lining while ensuring structural stability when a lining member made of precast concrete is transferred in the tunnel.
[0002]
[Prior art]
One of the applicants has developed a horizontal pulling method using bearing balls as friction reducing means as a rational laying method for precast concrete products such as box culverts (see, for example, Patent Document 1).
[0003]
FIG. 10 is a schematic side view showing a state in which the box culvert is laterally pulled as an example of the laying method. As shown in the figure, a horizontal pulling rail 103 is laid along the extending direction of the box culvert 102 on the foundation concrete 101 constructed in the excavation tunnel 100. As the horizontal pulling rail 103, a narrow H-shaped steel or the like in which most of the portion is embedded in the concrete 101 in a horizontal state as shown in FIG. One side of the embedded H-shaped steel web 103a serves as a rail surface, and a flange 103b with a slightly exposed end serves as a side wall. Further, bearing balls 104 as spherical bodies for reducing friction are arranged on the rail surface so as to be appropriately dispersed. For example, a steel ball having a diameter of about 11 mm is used for the bearing ball 104. On these bearing balls 104, a box culvert 102 having a guide plate 105 made of a thick steel plate fixed to the bottom surface is placed. The box culvert 102 is point-supported by a large number of bearing balls 104 via a guide plate 105. As shown in FIG. 10, as the box culvert 102 is pulled in the direction of the arrow by a lateral pulling (pulling) device such as a winch (not shown), the bearing ball 104 supporting the box culvert 102 rolls. Thereby, the dynamic friction between the guide plate 105 and the rail 103 is significantly reduced. According to experiments, the coefficient of dynamic friction is reduced to ¼ compared to the case of a horizontal pulling method such as warping. In FIG. 10 and FIG. 11, the bearing ball 104 is shown enlarged for explanation.
[0004]
By the way, in the tunnel structure formed by connecting a number of precast concrete members of unit width in the extending direction, not only the box culvert of the rectangular cross section described above, but also an arch-like shape applied as an upper half arch part constructed on the side wall concrete. A tunnel structure member made of precast concrete as a lining member is known. On the other hand, the applicant is carrying out an invention in which the above-described horizontal pulling method is applied as a method for continuously constructing this type of precast concrete tunnel arch member (see, for example, Patent Document 2). The present invention is a continuous construction method of a tunnel block in which a tension member is provided in order to stabilize the stress state of the arch, or a mechanically stable arch member provided with bottom slab concrete is laterally pulled.
[0005]
On the other hand, each figure in FIG. 12 shows, as another prior art, an arch shape made of precast concrete used for repairing an existing lining 161 of an old upper half arch of an existing tunnel 160 ((c) in the same figure). It is explanatory drawing which showed the construction condition of the lining member 150. FIG. The lining member 150 is an arch-shaped member made of precast reinforced concrete that is divided into two in the circumferential direction as shown in FIG. 1A, and the two members are connected to each other at the central top end 150a via bolts or the like. The arch shape is held by a shape-retaining jig 151 made of The lining member 150 is assembled for several spans in the tunnel extension direction outside the tunnel, suspended on the stand-by self-propelled assembly stand 152, fixed on the stand 152, and temporarily placed (same as above). (B). In this state, the assembly base 152 is moved, carried to the construction position of the lining member 150 in the tunnel, and the lining member 150 is attached to the existing lining using an anchor or the like in a state where a predetermined waterproofing is applied to the inside of the existing lining. It is designed to be fixed to the inner surface.
[0006]
FIG. 13 is a partial cross-sectional view showing an example of fixing the lining member 150 to the inner surface of the existing lining 161. Usually, as shown in FIG. 12C, the side wall concrete 162 for repair is constructed inside the existing lining 161, and the leg portions of the lining member 150 constituting the upper half arch portion on the side wall concrete top end face 162a. 150a is installed. FIG. 13A shows the leg 150 a of the lining member 150. As shown in the figure, a jack base 163 is attached to the bottom surface of the leg portion 150a, and the installation height of the lining member 150 is adjusted by adjusting the jack height. After the installation adjustment of the lining member 150 in the tunnel extending direction, the leg portions 150a of the lining member 150 are fixed to the existing lining side using the horizontal anchor bolts 164. Furthermore, after fixing a leg part with mortar, back grout is performed as needed.
[0007]
[Patent Document 1]
Japanese Patent No. 2879021 [Patent Document 2]
JP 2002-250044 (pages 2 to 3)
[0008]
[Problems to be solved by the invention]
By the way, in the arch-shaped lining work made of precast concrete described with reference to FIG. 12, the lining member placed on the traveling assembly frame is carried to the lining position in the tunnel, the attachment work is performed, and it is further emptied. The assembly frame is moved again to the outside of the tunnel mine, and the next process is repeated. For this reason, since all operations such as carry-in and lining attachment are performed using the assembly frame, there is a problem that the conveyance and assembly operations cannot be performed continuously, and the overall work efficiency is poor.
[0009]
In addition, as shown in FIG. 13, the support of the lining member 150 shown in FIG. 12C is rearranged on the side wall concrete 162 from the assembly base 152. At this time, as described above, the height of the lining member 150 is increased by the jack base 163. Work such as adjusting the height and fixing the legs with anchor bolts becomes necessary. At this time, in the case of a tunnel having a large upper half arch radius of the lining member 150, a horizontal force acting to open the arch outward is generated at the leg portion of the lining member 150, and the structural stability in the support state of the lining member 150 It was an important issue.
[0010]
Therefore, an object of the present invention is to apply the horizontal pulling method using the bearing ball as the friction reducing means described above, and to use the propulsion means outside the tunnel wellhead to stably support the arch-shaped precast concrete member. The present invention is to provide a continuous construction method of a tunnel block in which a continuous support is efficiently carried to a predetermined position in a stable support state, and the construction efficiency of the subsequent installation work is remarkably improved.
[0011]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the present invention forms a groove-like rail having a bottom surface formed at the inclination angle on the ceiling end surface of the side wall concrete in which the top end surface is inclined toward the tunnel inward at a predetermined inclination angle, On the grooved rail surface, a plurality of spherical bodies held in a powdery state are dispersed and arranged, and provided at a tunnel wellhead position, on an assembly frame that protects a vehicle passing below, an arch leg part Assemble the arch member of the tunnel block so that it is installed inside the upper half arch of the tunnel with the spherical body and powdery body in the grooved rail, and already standing near the wellhead in the tunnel The arch member is connected to the longitudinal direction of the tunnel, and a plurality of the arch members are sent to the tunnel depth by propulsion means installed outside the tunnel wellhead, and the arch leg portion is installed at the installation position. With Jo rails secured over with a filling material on the side wall on the concrete, characterized by constructing the lining arch continuing in the tunnel.
[0012]
As another invention, a groove-like rail is formed on the top end surface of the side wall concrete, and a plurality of spherical bodies held in a powdery body are distributed on the groove-like rail surface and arranged at the tunnel wellhead position. An arch leg having an upper surface fixed to a guide member having an inclination angle on a bottom surface of the leg having an inclination angle toward the inside of the tunnel at a predetermined inclination angle on an assembly frame that protects a vehicle passing underneath; Assembling the arch member of the tunnel block so that it is supported by the spherical body and the powder body in the groove-like rail and is erected inward of the upper half arch of the tunnel, and has already been erected near the wellhead in the tunnel The arch member is connected to the longitudinal direction of the tunnel, and a plurality of the arch members are sent to the back of the tunnel by propulsion means installed outside the tunnel well opening, and the arch leg portion is installed at the installation position. Wherein with groove-shaped rail and secured over with a filling material on the side wall on the concrete, characterized by constructing the lining arch continuing in the tunnel.
[0013]
The side wall concrete is constructed in contact with the side wall of the existing concrete, and the arch member is constructed so as to be located inside the tunnel of the existing lining arch portion, and the side wall concrete and the arch member are disposed on the existing cover. It is preferable to construct a new lining arch that is continuous inside the work.
[0014]
The side wall concrete is constructed along the excavated tunnel lower half ground surface, and the arch member is located inside the tunnel from the excavated natural ground arch portion that has been subjected to a predetermined waterproof treatment if necessary. It is preferable that the side wall concrete and the arch member constitute a lining arch that is continuous inside the upper and lower half-mountains.
[0015]
It is preferable to arrange and hold the side bearing balls along the groove side wall position of the grooved rail in order to reduce the friction during the transfer of the arch member.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a method for continuously constructing a tunnel block according to the present invention will be described with reference to the accompanying drawings.
1 to 3 are explanatory views showing the state of carrying in and assembling the arch-shaped lining member shown in each drawing of FIG. 12 as an application example of continuous construction of tunnel blocks.
[0017]
FIG. 1A is a sectional view of a tunnel to which a continuous construction method of a tunnel block according to the present invention is applied, and a lining member 1 constituting a part of an upper half arch is placed on a wall body (described later). FIG. 1 (b) shows a state in which the lining member 1 is placed at the tunnel wellhead on an assembly stand 20 installed to protect a general vehicle and a construction vehicle passing below. Yes. The construction state in the vicinity of the wellhead of the existing tunnel 10 is partially shown in the schematic tunnel longitudinal section, the plan view, and the side view of FIG. 2B shows a wall body 11 constructed along the inner surface of the side wall (not shown) of the existing tunnel 10. The wall body 11 functions as a support member for a grooved rail 13 to be described later of the lining member 1 at the time of temporary installation, and then supports the arch portion of the repair lining (hereinafter, the wall body is referred to as side wall concrete). Used as. Groove-like rails 13 are respectively provided on the top end surfaces of the side wall concrete 11 located on both sides of the tunnel. As shown in FIGS. 1, 4, and 5, the groove-like rail 13 has a parallelogram-shaped cross section that follows the top end face that is inclined so that the inner side of the tunnel is lowered at a predetermined inclination angle θ. It has a groove shape.
[0018]
That is, in the lining member 1 assembled so as to close the upper half arch as shown in FIG. 5, the weight W of the lining member 1 tends to spread in the vertical direction and the lower end of the arch toward the outside on the leg portion 1 a. A horizontal force H acts. Therefore, stable support is possible by supporting the leg portion 1a of the lining member 1 with a plane P (which forms an inclination angle θ with the horizontal plane) perpendicular to the direction of the resultant force R of the two forces. Therefore, the groove-like rail 13 on the top end surface of the side wall concrete 11 is inclined according to this angle θ, and is configured as a slope. In the groove-like rail 13, as shown in FIG. 4, a large number of bearing balls 14 as spherical bodies that reduce friction are appropriately arranged in the extending direction of the groove-like rail 13. And the powder-like body 15 is filled in the groove-shaped rail 13 so that this bearing ball 14 may not roll on the slope. In the present embodiment, a steel ball having a diameter of about 11 mm is used as the bearing ball 14, and the dry powder 15 is filled with dry sand.
[0019]
In addition, although the above-mentioned side wall concrete 11 is constructed with a cast-in-place concrete, a precast concrete member to which a grooved rail is attached may be assembled on the spot. Needless to say, the tunnel to be applied may be a new lining for a new tunnel or a modified lining of an existing tunnel.
[0020]
Each figure of FIG. 2 has shown the state by which the lining member 1 was assembled | assembled on the assembly stand 20 installed in the tunnel well vicinity vicinity. At this time, the lining member 1 is placed on the groove-shaped rail described above. And the propulsion jack for moving this lining member 1 in the tunnel back direction is shown. As shown in FIG. 1 (b), the assembly base 20 is a stationary structure installed at a tunnel wellhead, and is made of a steel frame in which a pillar portion 22 and a mountain frame 23 that are erected on a foundation concrete 12 are assembled. Become. A rail (not shown) that is set to the same height as the groove-like rail 13 on the side wall concrete 11 described above with the top 23a and both shoulders 23b of the mountain-shaped frame 23 as guides and that communicates with the groove-like rail 13 is provided. Yes. Thereby, the lining member 1 assembled on the assembly base 20 can be moved on the grooved rail 13 as it is. In the present embodiment, as shown in FIG. 2B, two divided lining members 1 connected at the arch top end are connected in two lines in the extending direction to form one unit for conveyance. The longitudinal direction between the arch top end and the lining member 1 adjacent in the extending direction is connected by a connecting bolt (not shown). Note that the space below the assembly base 20 also serves as a protector so as not to block the passage of the vehicle C even when the lining member 1 is suspended and connected. For connecting the lining members in the longitudinal direction, a more efficient joining operation can be performed by using a one-touch type joint or the like.
[0021]
As shown in FIG. 2, the propulsion jack 25 is equipped such that a plurality of cylinder rods 27 are disposed horizontally on a jack mount 26 installed at a position further forward than the assembly mount 20. The rear end 25 a is fixed to the bearing plate 28. On the other hand, a pressing plate 29 is attached to the tip of a plurality of cylinder rods that operate synchronously. As shown in FIG. 2A, the two propulsion jacks 25 can extend and retract the cylinder rod 27 while synchronizing them, and the pressing plate is applied to the leg portion 1a of the lining member 1 placed on the assembly base 20. 29, the lining member 1 can be moved to the back of the tunnel by the extension operation of the cylinder rod 27.
[0022]
At this time, as shown in FIG. 4, the lining member 1 is placed on the bearing ball 14 that is held and accommodated by the powdery body 15 in the groove-like rail 13 formed on the side wall concrete 11. Is placed. For this reason, as shown in FIGS. 2 to 3, when the leg portion 1a is pushed to the back of the tunnel by the extension of the cylinder rod 27 of the propulsion jack 25, the entire lining member slides easily and has already been built from the tunnel wellhead. Rarely, it is pushed towards the lining member 1 connected as part of the lining. In particular, FIG. 3 shows a state in which the cylinder rod 27 of the propulsion jack 25 is completely extended. In this state, the lining member 1 is completely located in the tunnel and has already been connected as part of the tunnel lining. A plurality of units can be further propelled to the back of the tunnel from the rear end of the arch member. At this time, by interposing a synthetic rubber-based or foamed resin-based cushion material (not shown) between the already connected lining members, the lining member can be prevented from being damaged. Further, when the tunnel extension becomes long, there is a possibility that the continuous jacking span cannot be pushed in with the propulsion jack installed at the wellhead even if the dynamic friction of the grooved rail is small. Therefore, when the tunnel extension is long, it is also preferable to provide an intermediate push jack at an intermediate position.
[0023]
6 and 7 are enlarged cross-sectional views showing the shape of the groove-like rail 13 formed on the top end surface of the side wall concrete 11, and the bearing balls 14 and the powdery body 15 accommodated therein. When the lining member 1 is transferred to the depth of the tunnel, an outward horizontal force H (see FIG. 5) acts on the lining member 1 and moves sideways in the grooved rail 13, and is positioned on the bottom surface of the lining member 1. As a result, the side surfaces of the guide plate 16 competing to be pressed against the side surfaces of the grooves may increase friction during transfer. In order to prevent this, in the present embodiment, the bearing balls 14 are arranged in a line along the side surface of the groove. That is, as shown in FIG. 6 (a), the upper surface of the ball holding bar 17 attached in a step shape by extending a thin bar-like ball holding bar 17 in the rail extending direction on the outer bottom of the groove. The side bearing balls 18 are held in contact with the side surfaces of the grooves in the rail extending direction. As a result, the friction can be sufficiently reduced against the pressing force to the side. In FIG. 6A, a ball holding bar 17 is also provided inside the grooved rail 13 (on the inner side of the tunnel), so that the legs of the lining member 1 constituting the tunnel arch move so as to shift toward the inner side of the tunnel. Even if it has been done, the influence on the transfer of the lining member 1 in the tunnel depth direction can be minimized. In the modification shown in FIG. 6B, the top end surface of the side wall concrete 11 is finished horizontally, and a grooved rail 13 is formed on the top end surface. In the same manner as in FIG. 5A, the bearing ball 14 and the powdery body 15 are accommodated. At this time, by setting the upper surface 16a of the guide plate 16 to the inclination angle θ as shown in the drawing, the configuration of the arch leg portion similar to that shown in FIG.
[0024]
FIG. 7A is a detailed cross-sectional view corresponding to FIG. 6A, and shows an example in which a narrow-width H-section steel is used as the groove-like rail 13 as shown in FIG. 11. As shown in the figure, the position of the bearing ball 14 in the groove is held by the powdery body 15 even when the grooved rail 13 is formed on the top end surface of the side wall concrete 11 at a predetermined inclination angle θ. The side bearing ball 18 is disposed between the guide plate 16 and the flange 13b by the ball holding bar 17 fixed to a part of the flange 13b of the shape steel constituting the groove wall. The side bearing balls 18 prevent the guide plate 16 from competing with the flange 13b and reduce the friction. In the present embodiment, the cover 19 is fixed in the rail extension direction in order to prevent the side bearing balls 18 from jumping out of the rail. FIG. 7B is a detailed cross-sectional view corresponding to FIG. In this case, the same is true except for the cross-sectional shape of the guide plate.
[0025]
FIG. 8 is a partially enlarged cross-sectional view showing a modified example of the grooved rail formed on the top end surface of the side wall concrete 11 and the guide plate formed on the lower surface of the lining member. As shown in the figure, in this modification, the grooved rail and the guide plate are made of hardware having substantially the same shape. Each hardware is arranged at a predetermined interval in the thickness direction of the base plate 40 extending in the rail extending direction and the side wall concrete 11 or the lining member 1, and extends in the rail extending direction fixed to the surface of each plate 40. A ball holding member 41 is used. The ball holding member 41 is an elongated bar having a quadrangular cross section, and the overall cross-sectional shape to which the ball holding member 41 is attached has a comb shape. The grooved rails and the comb teeth of the guide plate are fixed to the side wall concrete 11 and the lining member 1 so as to face each other with the bearing ball 14 therebetween. Each bearing ball 14 does not roll down along the inclination by the lower bar 41. Further, since the bearing ball 4 is supported by the powdery body 15, the bearing ball 14 can be reliably prevented from moving in the tunnel longitudinal direction. By adopting such a configuration, it is possible to reliably prevent the lining member 1 from competing against the groove side wall due to the horizontal force directed outward.
[0026]
FIGS. 9A and 9B are partial cross-sectional views showing a method for fixing the leg portion after the lining member 1 is installed. FIG. 9A shows a case where the lining member 1 is used for lining a new tunnel. As shown in FIG. 9A, the mold 5 is attached to the upper end of the side wall concrete 11, and a groove is formed from a grout hole (not shown) provided in a part of the mold 5 at a predetermined interval in the longitudinal direction. The leg grout 6 is performed so that the bearing balls 14 in the rail 13 and the powdery body 15 are integrated. As the grout strength at this time, it is preferable to employ a mortar exhibiting a predetermined strength so that the leg portion 1a of the lining member 1 is structurally fixed on the side wall. Further, a backfill grout 7 for filling a gap between the back surface of the lining member 1 and the ground is formed. The backfill grout is preferably a filler such as air mortar that has sufficient permeability and foamability so as not to leave a gap between the lining member 1 as the lining. In addition, in order to perform the spring water treatment from the natural ground, a waterproof sheet is sometimes applied to the natural ground. In this case, sufficient adhesion is provided between the waterproof sheet (not shown) and the lining member 1. It is preferable to select a grout material that can be exhibited. FIG. 9B shows an example in which the newly installed lining member 1 is installed on the inner side of the existing lining 10 in the lining repair work of the existing tunnel. Moreover, when the soundness of the existing lining 10 is sufficient, it is possible to use the lining member 1 as a decorative board and to eliminate the need for backfill grout.
[0027]
【The invention's effect】
As described above, lining members assembled in the shape of arches made of precast concrete members can be assembled continuously in the tunnel in a structurally stable state and moved to the back of the tunnel for installation. This makes it possible to construct lining concrete with remarkable construction efficiency.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an assembled and supported state of lining members in a tunnel and outside a wellhead according to the present invention.
FIG. 2 is a plan view and a side view showing an assembled state of the lining member in the vicinity of the tunnel wellhead shown in FIG.
3 is a plan view and a side view showing a propulsion state of a lining member in the tunnel mine shown in FIG. 1. FIG.
FIG. 4 is a partial sectional view showing a support state of an arch leg portion of a lining member on side wall concrete during propulsion.
FIG. 5 is a schematic diagram showing the acting force on the leg in a state where the lining member is assembled.
FIG. 6 is a partial cross-sectional view showing a state where a leg portion of a lining member on side wall concrete is supported.
FIG. 7 is a detailed cross-sectional view showing a leg portion supporting state of the lining member on the side wall concrete.
FIG. 8 is a detailed sectional view showing a modified example of the grooved rail.
FIG. 9 is a partial cross-sectional view showing an example of a fixed state of a leg portion of a lining member installed in a tunnel.
FIG. 10 is a side view showing an example of a conventional pipe laying continuous construction work.
11 is a partial front view showing an example of friction reducing means in the continuous laying work of the pipe rod shown in FIG.
FIG. 12 is an explanatory diagram of a construction state showing an example of a conventional method for installing a lining member.
FIG. 13 is a partial enlarged cross-sectional view showing an example of a conventional method for fixing a leg portion in a tunnel of a lining member.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Lining member 10 Tunnel 11 Side wall concrete 12 Foundation concrete 13 Grooved rail 14 Bearing ball 17 Ball holding bar 18 Side bearing ball 20 Assembly stand

Claims (5)

A grooved rail is formed on the ceiling end surface of the side wall concrete with the top end surface inclined toward the inside of the tunnel at a predetermined tilt angle, and the bottom surface is formed at the tilt angle. A plurality of spherical bodies held in position are distributed and arranged at a tunnel wellhead position on an assembly frame that protects a vehicle passing underneath, and an arch leg is connected to the spherical body in the grooved rail. Assemble the arch member of the tunnel block so that it is supported by the powder body and is built inward of the upper half arch part of the tunnel, and it is connected to the arch member already erected near the wellhead in the tunnel in the tunnel longitudinal direction. The plurality of arch members are sent to the depth of the tunnel by the propulsion means installed outside the tunnel wellhead, and the arch legs together with the grooved rails are installed in the side wall control at the installation position. Covered with a filler fixed on preparative, continuous construction method of tunnel blocks, characterized in that constructing a lining arch continuing in the tunnel. A grooved rail is formed on the top end surface of the side wall concrete, and a plurality of spherical bodies held in the powdery body are distributed on the grooved rail surface, arranged at the tunnel wellhead position, and passing below. An arch leg having an upper surface fixed to a guide member having an inclination angle on the bottom surface of the leg portion having an inclination angle toward the inside of the tunnel at a predetermined inclination angle on the assembly frame for protecting the vehicle, the groove-shaped rail Assembling the arch member of the tunnel block so as to be supported by the spherical body and the powder body in the tunnel and erected inward of the upper half arch portion of the tunnel, and the arch member already erected in the vicinity of the wellhead in the tunnel; A plurality of the arch members are sent to the depth of the tunnel by propulsion means connected in the longitudinal direction of the tunnel and installed outside the tunnel wellhead, and the arch legs are attached to the groove-like rails at the installation position. Both the side wall covered with a filling material is fixed on the concrete, the continuous method of constructing a tunnel blocks, characterized in that constructing a lining arch continuing in the tunnel. The side wall concrete is constructed in contact with the side wall of the existing concrete, and the arch member is constructed so as to be located inside the tunnel of the existing lining arch portion, and the side wall concrete and the arch member are disposed on the existing cover. The continuous construction method of the tunnel block according to claim 1 or 2, wherein a new lining arch is formed inside the construction. The side wall concrete is constructed along the excavated tunnel lower half ground surface, and the arch member is located inside the tunnel from the excavated natural ground arch portion that has been subjected to a predetermined waterproof treatment if necessary. The tunnel block according to claim 1 or 2, wherein the side wall concrete and the arch member constitute a lining arch that is continuous inside the upper and lower half-mountains. Continuous construction method. The method for continuously constructing a tunnel block according to claim 1 or 2, wherein side bearing balls are arranged and held along a groove side wall position of the grooved rail.

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