JP2005083014A - Pre-cast tunnel method and member conveyor used therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pre-cast tunnel method and a member conveyor used therefor capable of being installed by easily conveying a pre-cast concrete member forming a lining body of a tunnel without having an influence on external environment of a tunnel construction space when a tunnel construction work is carried out while ensuring traffic by a protector in a pre-cast tunnel method and a member conveyor used therefor. <P>SOLUTION: A guide rail 5 is constructed on the upper part of the protector 4 provided on the road 3, and a conveying truck 7 is traveled thereon. The conveying truck 7 is equipped with an arm 26, and arch type panels 8A and 8B are slightly lifted upward from predetermined installation locations so that the member conveyor can be conveyed in the direction of tunnel extension by holding an arch-shape. After the member conveyor is conveyed in the direction of tunnel extension by the conveying truck 7, the arm 26 is dropped to connect it with the existing panel, and arch type tunnels are successively extended. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a precast tunnel method and a member conveying device used therefor.

In recent years, demand for widening existing tunnels has increased due to an increase in traffic volume. In such widening tunnel construction, it is important that construction can be performed without blocking the traffic in the existing tunnel, and it is desired that construction can be performed quickly.
Therefore, conventionally, a method of installing a protector that encloses a traffic path in an existing tunnel in the width direction to ensure traffic safety and performing widening tunnel construction outside the protector is known. For example, after a protector is installed, the existing tunnel is excavated, and an arch-shaped precast concrete member surrounding the protector is transferred from a stockyard by a crane and assembled.
For example, Patent Document 1 describes a construction method of an arch type tunnel in which a pair of precast concrete arc plates that divide a tunnel arch into approximately two parts is assembled on a ground that has been cut and connected in the tunnel extending direction.
JP-A-8-109645 (page 2-3, FIG. 1)

However, the conventional precast tunnel method and the tunnel working apparatus as described above have the following problems.
In the construction method of installing a protector and assembling a precast concrete member (hereinafter abbreviated as a precast member or PC member) above it, it is possible to perform a quicker construction than a construction method of forming a lining body with cast-in-place concrete, Depending on the installation environment of the tunnel, there is a problem that it is difficult to install a storage place for materials such as PC members and a crane. Therefore, in such a case, there has been a problem that the PC member must be transported in the tunnel extending direction by blocking the tunnel traffic.
In the technique described in Patent Document 1, although a construction method of an arch type tunnel that assembles a precast concrete arc plate is described, there is no specific description about a method of conveying such a precast concrete arc plate, There is no particular description of a method of transporting without blocking the traffic path. Therefore, it has the same problem as the general construction method for assembling the above PC member.

  The present invention has been made in view of the above problems, and when performing tunnel construction while securing traffic with a protector, a precast concrete member that forms a tunnel lining body is used as an external environment of the tunnel installation space. It is an object of the present invention to propose a precast tunnel method that can be easily transported and installed without being influenced by the above, and a member transport device used therefor.

In order to solve the above-mentioned problems, in the invention according to claim 1, in the precast tunnel construction method in which a protector is temporarily installed on a traffic road, a plurality of precast members are installed above and a tunnel is constructed by joining together. A guide mechanism extending along a tunnel extending direction is provided at an upper portion of the protector; a travel mechanism capable of traveling above the guide means; and a travel mechanism provided on the travel mechanism, wherein the precast member is within a predetermined range. The precast member is held at the member holding position close to the installation position in the cross section in the tunnel radial direction, and in this state, the tunnel extension is performed along the tunnel extension direction. A precast member transporter that transports to the installation position in the installation direction and moves to the installation position in the tunnel radial section. The method comprising a.
According to the present invention, since the guide means of the member transport device is provided on the upper part of the protector, the guide means and the transport space of the member transport device can be transported without being provided on both sides of the protector, and the height of the member transport device can be increased. Can be lowered.
Also, since the precast member is held at the member holding position close to the installation position in the tunnel radial direction cross section and moves along the tunnel extending direction in that state, the movement amount in the tunnel radial direction cross section at the time of holding and installation Therefore, easy, quick and safe installation is possible.
Further, since the moving cross section of the precast member is substantially the same as the installation cross section of the tunnel, it can be easily transported without being influenced by the installation environment on the outer periphery side of the tunnel.

According to a second aspect of the present invention, in the precast tunnel construction method according to the first aspect, the precast member is an arch forming member that bisects a tunnel radial direction cross section from a vertical central axis, and holds the member conveying device. The construction method is such that the moving direction by the mechanism is substantially vertical.
According to the present invention, it is possible to easily hold the two arch forming members from the side of the member conveying device without lifting the arch forming members, transport them while holding them in an arch shape, and join them by simply lowering them. Therefore, joining after conveyance can be performed quickly. Further, since the holding mechanism only moves substantially in the vertical direction, the holding mechanism can be a simple mechanism.

According to a third aspect of the present invention, there is provided a member transport device used in a precast tunnel construction method in which a protector is provided on a traffic road, a plurality of precast members are installed above and joined to each other, and a tunnel is constructed. A travel mechanism capable of traveling above the guide means along the tunnel extending direction provided in the upper portion of the head, and a holding mechanism for holding the precast member variably within a predetermined range.
According to this invention, since it can be set as the member conveyance apparatus suitable for using for the precast tunnel construction method of Claim 1, it has the same effect.

  According to the precast tunnel method of the present invention and the member conveying device used therefor, the precast member held at the member holding position close to the predetermined installation position of the tunnel radial direction sectional phase is extended through the tunnel using the upper space of the protector. Since the precast member is installed by moving to the predetermined installation position of the tunnel radial cross section after transporting in the direction, the precast member can be transported in the same space as the radial cross sectional area of the tunnel to be installed. There is an effect that it can be easily transported and installed without being influenced by the external environment of the installation space.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic explanatory view in plan view for explaining a precast tunnel construction method according to an embodiment of the present invention. FIG. 2A is a cross-sectional view taken along line AA in FIG. FIG. 2B is a cross-sectional view taken along the line BB in FIG. 3 is a cross-sectional view taken along the line CC in FIG. 4 is a cross-sectional view taken along the line DD in FIG. FIG. 5 is a schematic explanatory diagram viewed from E in FIG.

A precast tunnel method according to an embodiment of the present invention will be described.
In the precast tunnel construction method of the present embodiment, as shown in FIG. 1, the protector 4 is provided above the road 3 to secure traffic, and the ground 1 is excavated, and an arch-type tunnel 80 (tunnel) is formed thereon. In particular, when an existing tunnel is provided on the road 3, the existing tunnel is removed, an arch-type tunnel 80 having a larger cross-sectional diameter is constructed, and the widened tunnel backfilling the excavated portion This method is suitable for construction. Below, it demonstrates taking the case of such a wide tunnel construction as an example.
Since such construction is performed while securing traffic, the work space is limited, and generally the work is performed in a narrow excavation area on the side of the road, and the necessity for shortening the construction period is high. Therefore, a precast tunnel construction method is adopted in which the arch type tunnel 80 is constructed by assembling the arch type panels 8A and 8B (precast members), which are PC members manufactured in a factory away from the installation site, above the protector 4. There is a case.
Conventionally, in such a tunnel construction method, the arched panels 8A and 8B are temporarily placed in a place such as a work area 6 slightly away from the actual installation position, and are lifted to the installation position using a heavy machine such as a crane K. I was carrying it. This is because it is usually difficult to provide a wide work area 6 near the tunnel construction site.
This construction method is characterized in that, instead of such a conventional precast member conveyance step, a precast member conveyance step using the conveyance carriage 7 according to the embodiment of the member conveyance device of the present invention is provided.

The configuration of the completed arched tunnel 80 will be briefly described with reference to FIG.
The arch type panels 8A and 8B are each an arc plate-like member having a shape in which an arch shape forming the upper half section of the arch type tunnel 80 is divided into left and right sides with the vertical center line of the tunnel as a boundary and extended in the depth direction of a predetermined width. It is.
Both the arch type panels 8A and 8B are provided with a plurality of joint portions (not shown) that can be bolt-nut joined to the zenith joint surfaces 8a and 8a that are one end surface in the circumferential direction and the end surfaces in the depth direction. . Further, through the bottom joint surfaces 8b and 8b, which are the other end surfaces, there are provided through holes (not shown) for inserting a PC steel rod in the vertical direction and placing the mortar to fix it to the foundation.
The zenith joint surfaces 8a and 8a are fastened with bolts and nuts to form an arch structure having a predetermined width. Then, such an arch structure is positioned in the tunnel width direction, and the end surfaces in the depth direction are sequentially connected by bolts and nuts, and the bottom joint surfaces 8b and 8b respectively sandwich the road 3 on the left and right in the tunnel extending direction. The arch-shaped tunnel 80 is extended by being fixed to the panel support surfaces 9a and 9a which form the upper surfaces of the foundations 9A and 9B constructed in the above. Then, above the outer peripheral surfaces 8d of the arched panels 8A and 8B, the excavated soil is backfilled to form the ground 1.

As shown in FIG. 2B, the protector 4 is a plate-like member in which a U-shaped cross section covering the upper side of the road 3 is extended by a predetermined width in the depth direction, and the top plate 4a, the side plates 4b, 4b are Provided, and the end portions in the width direction can be connected to each other by, for example, bolt-nut fastening. Then, a plurality of them are connected in the depth direction without gaps so that the safety of traffic on the road 3 can be ensured within a necessary range.
The size of the protector 4 is set to a size that fits inside the existing tunnel lining inner surface 12 so that it can be placed before the existing tunnel is removed. Therefore, a wider space than the existing tunnel lining inner surface 12 is formed between the outer peripheral side of the protector 4 and the inner peripheral surface 8 c of the arched tunnel 80. A work scaffold 4c (see FIG. 3) may be appropriately provided on the outer portion of the protector 4. The material of the protector 4 is, for example, a steel structure that uses H-shaped steel as a column and a beam and forms a wall surface with a steel plate. Can be adopted.
An appropriate fixing member (not shown) can be fastened to a bolt at a predetermined position on the top plate 4a, and a guide rail 5 described later can be detachably installed.

The outline of the precast tunnel construction method of this embodiment consists of a protector installation process, an excavation process, an existing tunnel removal process, a foundation installation process, a precast member transport process, a precast member connection process, and a backfill process.
In the protector installation process, as shown in FIG. 3, the protector 4 is installed inside the existing tunnel lining inner surface 12 so as to cover the road 3, and is extended by the length of a necessary construction section.
Although this process is performed by temporarily blocking traffic in the middle of the night, for example, after the protector 4 is installed, traffic safety is ensured, so that it is not necessary to block traffic.
In the excavation process, temporary earth retainings 10 (see FIG. 2) are installed on the left and right sides in the extending direction of the existing tunnel, and the space between them is excavated and discharged.
In the existing tunnel removal process, the existing tunnel is removed using a crushing device. And after eliminating crushing shear etc., the guide rails 5 and 5 (guide means) are laid along the tunnel extending direction on the top plate 4a.
The guide rail 5 is a steel track member for running a transport carriage 7 described later.
In the foundation installation step, the foundations 9A and 9B are installed by placing concrete in positions that support the arched panels 8A and 8B. The panel support surfaces 9a of the foundations 9A and 9B are adjusted so that the left and right levels are equal, and an incision bar (not shown) for fixing the arch type panels 8A and 8B is provided. Further, a mounting portion for attaching a fixing bolt for fixing the position until the arched panels 8A and 8B are securely fixed to the panel support surface 9a is appropriately provided.

In the precast member conveyance process, the arch type panels 8A and 8B are held on the conveyance carriage 7, moved on the guide rail 5, and the arch type panels 8A and 8B are installed at predetermined positions.
Here, the configuration of the transport carriage 7 will be described with reference to FIGS. FIGS. 3 and 4 respectively show a schematic front view shape and a central sectional shape of the transport carriage 7. FIG. 5 is a plan view of the transport carriage 7.
The schematic configuration of the transport carriage 7 includes a carriage base 30, a self-propelled mechanism 20 (traveling mechanism), an arm 26, a main lift mechanism 27, a lateral slide mechanism 28, and a turning mechanism 29.
In the following, when referring to the direction related to the transport carriage 7, for the sake of convenience, the abbreviations are as follows. When placed on the guide rail 5, the side on which the arched panels 8A and 8B are placed (the left side in the figure, the lower side in the figure) is the rear side, and the same side (the right side in the figure, the right side). 5 is referred to as the front side, the direction connecting them is the front-rear direction, and the left and right when the front side is viewed on the transport carriage 7 is referred to as the left and right of the transport carriage 7.

The carriage base 30 forms the main body of the transport carriage 7, is made of a substantially rectangular flat plate member extending between the guide rails 5, 5, and is provided with four wheels 20 a having axles parallel to each other on the lower surface side. The guide rails 5 and 5 can be moved.
On the upper surface of the carriage base 30, work tables 34 and 34 extending in the tunnel width direction are provided on the end side in the front-rear direction so that the operator 13 can move and work.

  The self-propelled mechanism 20 includes a motor for driving the wheels 20a to rotate and a drive transmission unit, and is capable of moving on the guide rail 5 while holding the arched panels 8A and 8B. It is provided on the front side of the lower surface of the table 30. A rail clamp 21 (see FIGS. 4 and 5) provided in front of the self-propelled mechanism 20 is for preventing the wheel 20 a from being removed and ensuring movement along the guide rail 5.

As shown in FIG. 3, the arm 26 is a support member that includes an arm horizontal portion 26a and arm bent portions 26b and 26b that bend obliquely downward from the left and right ends thereof. 34 and 34, and is provided above the carriage base 30 in a front view. The short width of the arm 26 is approximately the same as the width of the arched panels 8A and 8B.
The arm horizontal part 26a is fixed to the upper part of the main lift mechanism 27, and is movable in the vertical direction. Two main lift mechanisms 27 are provided at the left and right end portions of the carriage base 30, respectively, and can be expanded and contracted in the vertical direction while supporting the weight of the arch type panels 8A and 8B, and the arch type panels 8A and 8B are moved up and down. It is a mechanism for moving in the direction.
The arm bent portion 26b is provided with a panel locking portion 25 for holding the arched panels 8A and 8B on the upper surface side of the lower end.
In FIG. 3, in order to represent the positional relationship when the arm 26 is raised and lowered, the arrangement when the arm 26 is lowered is shown on the left side, and the arrangement when the arm 26 is raised is shown on the right side. Actually, the left and right main lift mechanisms 27 are driven simultaneously, and the arm horizontal portion 26a is moved up and down while maintaining the horizontal.

When the panel locking portion 25 has a shape that engages with the panel mounting bracket 11 mounted on the intermediate portion of the inner peripheral surface 8c of the arched panels 8A and 8B, for example, when the panel mounting bracket 11 has an arc-shaped groove, The engaging portion 25 is provided with a cylindrical portion that engages with the engaging portion 25 in the vertical direction. The position is adjustable by being supported by a hydraulically driven slide mechanism 24 provided on the arm bent portion 26b so as to be extendable and retractable along the inclination direction of the arm bent portion 26.
Further, on the upper side of the intermediate part of the arm horizontal part 26a, the position can be adjusted in the vertical direction by the jack 23, and the auxiliary roller which is in smooth contact with the inner peripheral surface 8c of the arch type panels 8A and 8B and is supported from below. 23a is provided.
The panel mounting bracket 11 is provided on the outer side in the tunnel width direction with respect to the gravity center position G when the arch type panel 8A (8B) is placed at a predetermined member holding position.

In order to finely adjust the postures of the arched panels 8A and 8B held by the arm 26, a lateral slide mechanism 28 and a turning mechanism 29 are provided between the carriage base 30 and the arm 26 by hydraulic drive. It is done.
In addition, the hydraulic pressure supply and hydraulic control of the hydraulic drive device including these are performed by the hydraulic unit 32.
Furthermore, electric power required for the hydraulic unit 32, the self-propelled mechanism 20, and the like is supplied from the outside of the transport carriage 7 by an electric cable 22a held on the cable reel 22, and a necessary driving operation can be performed by the control unit 33.

  According to such a transport carriage 7, since the guide rail 5 is provided and moved on the protector 4, the height of the apparatus can be reduced as compared with the case where the guide rail 5 is provided on the road surface of the excavation area. There is an advantage that a small device can be obtained.

Next, the operation | movement which conveys arch type panels 8A and 8B using such a conveyance trolley 7 is demonstrated.
The transport carriage 7 is initially waited on the protector 4 away from the joining work position of the arched panel 8B (8A). Then, as shown in the right half of FIG. 3, with the arm 26 raised to the member holding position, the arched panel 8B (8A) is lifted up to the upper side of the arm 26, and the panel mounting portion 25 is attached to the panel mounting bracket. 11 to be engaged.
The member holding position is a position where the arch type panel 8B (8A) can be arranged at a position where the predetermined installation position in the tunnel radial direction is substantially translated to a predetermined height slightly higher than the predetermined installation position. This predetermined height is a height at which the base 9B (9A) can be moved in the tunnel extending direction without any obstacles. For example, the bottom joint surface 8b is higher than the height of the incision bar (not shown) on the panel support surface 9a. As low as possible. Therefore, when the arm 26 is lowered below the predetermined height, the arched panel 8B (8A) is arranged at a substantially predetermined installation position.
In order to arrange the arm 26 at such a member holding position, if necessary, the jack 23, the slide mechanism 24, the lateral slide mechanism 28, the turning mechanism 29, and the like are appropriately driven so that the posture of the arched panel 8B (8A) is increased. Adjust.

At this time, since the center of gravity G of the arched panel 8B (8A) is located on the inner side of the panel mounting bracket 11 in the tunnel width direction, a rotational moment is applied to lower the zenith joint surface 8a. A stable posture is pressed against the auxiliary roller 23a from above.
Moreover, since the arch type panel 8B (8A) has a shape in which the tunnel arch is divided into two in the left-right direction, in order to hold it as described above, it can be placed from the left and right of the transport carriage 7, for example, There is an advantage that it can be easily placed because it does not have to be lifted high in order to straddle the protector 4 and the transport carriage 7 as in the case of placing a PC member that is previously arched.

In this manner, the pair of arched panels 8A and 8B having a substantially predetermined installation posture are held in an arch shape extending over the transport carriage 7 and the protector 4 except for being lifted by a predetermined height. Then, while the state is maintained, the transport carriage 7 is advanced by the self-propelled mechanism 20 and transported to a predetermined installation position in the tunnel extending direction.
Then, while again finely adjusting the postures of the arched panels 8A and 8B, the end surfaces in the width direction are lowered to a predetermined installation position while contacting the existing arched panels 8A and 8B.
Thus, the precast member conveyance process is completed.

In the precast member conveyance process of this embodiment, since the load is equally applied to the conveyance carriage 7, there is an advantage that it can be stably conveyed.
In addition, since the moving cross section is slightly higher than the tunnel cross section and has substantially the same area as the tunnel cross section, the moving cross section can be smoothly transported even when the cut surface 2 and the temporary earth retaining 10 are close to each other. There is an advantage that you can.
Further, since the lifting height and distance are relatively small, the operation can be made easier and safer.
Further, since the guide rail 5 is provided on the top plate 4a of the protector 4, a sufficient working space can be secured and the guide rail 5 is not buried in the earth and sand. Compared with the case of enlarging the surface, there is an advantage that the laying work becomes much easier.

Next, in the precast member connecting step, in the above state, bonding between the zenith portion bonding surfaces 8a and 8a, bonding to the existing panel, and bonding to the foundations 9A and 9B are performed. For joining to the foundations 9A and 9B, for example, a position in the tunnel width direction is temporarily fixed with a fixing bolt, and mortar is placed in a through hole through which a reinforcing bar is inserted to be cured and bonded.
In this step, since the arm 26 is stopped at a position where the arch type panels 8A and 8B are supported from below, the function similar to that of the temporary column conventionally used for temporarily receiving the arch type panels 8A and 8B. And guarantees the safety of joining work.

When the bolt fastening is completed and the arch is self-supporting, as shown in the left half of FIG. 3, the arm 26 is lowered until the panel locking portion 25 is detached from the panel mounting bracket 11, and the transport cart 7 To prepare for the next precast member conveying step.
In this way, the arch of the arch-type tunnel 80 is extended, the protector 4 is removed from the area where the tunnel is completed, and moved to a new construction section, and the guide rail 5 is moved accordingly.
Then, a backfilling process is performed from the area where the installation of the arched panels 8A and 8B is completed.
In this way, the arched tunnel 80 can be constructed.

  In the above description, as shown in FIG. 1, the arched panels 8A and 8B are described as being joined with the zenith joining surfaces 8a facing each other, but this is an example, and the arched panels The two arched panels 8B halves may be joined to 8A and joined in a staggered manner in plan view. In that case, when it hold | maintains at the conveyance trolley 7, it can construct | assemble by the process similar to the above except making the state which made the arch type panels 8A and 8B half-shift to the tunnel extension direction. Moreover, since the structure of the conveyance trolley 7 for that is easily understood from said description, description is abbreviate | omitted.

In the above description, the example of tunnel widening has been described, but it goes without saying that the present invention can also be applied to the case where an arched tunnel is provided on an existing road.
In the above description, the example in which the precast member is an arch forming member that divides the tunnel arch into two parts has been described. However, if necessary, a precast member that divides the arch into two or more parts may be used.

In the above description, the member holding position has been described as a position where the precast member has been moved upward by a predetermined height from the predetermined installation position in the tunnel radial direction cross section, but the holding mechanism includes a moving mechanism other than the vertical direction, The position is not limited to such a position as long as the movement in the tunnel extending direction is not hindered. For example, a mechanism for moving in the tunnel radial direction may be provided, and a position where the precast member is moved a predetermined distance in and out of the tunnel radial direction may be set as the member holding position.
For example, if the member holding position is on the inner side in the tunnel radial direction, the present invention can also be applied to the case where the lining body is formed from the inner surface of the tunnel using a precast member in a tunnel method other than the open-cut tunnel method.

It is a plane view schematic explanatory drawing for demonstrating the precast tunnel construction method which concerns on embodiment of this invention. It is AA sectional drawing and BB sectional drawing in FIG. It is CC sectional drawing in FIG. It is DD sectional drawing in FIG. FIG. 5 is a schematic explanatory diagram viewed from E in FIG. 4.

Explanation of symbols

3 roads (traffic roads)
4 Protector 4a Top plate (above the protector)
5 Guide rail (guide means)
7 Carriage cart (member conveyance device)
8A, 8B Arch type panel (Precast member)
9A, 9B Foundation 11 Panel mounting bracket 20 Self-propelled mechanism (traveling mechanism)
20a Wheel 23 Jack 23a Auxiliary roller 24 Slide mechanism 25 Panel locking part 26 Arm (holding mechanism)
27 Main lift mechanism 28 Lateral slide mechanism 29 Turning mechanism 30 Carriage base 80 Arch type tunnel (tunnel)

Claims (3)

A precast tunnel construction method in which a protector is temporarily installed on a traffic road, a plurality of precast members are installed above and a tunnel is constructed by joining together,
Provide guide means along the tunnel extending direction at the top of the protector,
A member transport device having a traveling mechanism capable of traveling along the guide means and a holding mechanism provided on the traveling mechanism and variably holding the precast member within a predetermined range;
The precast member is held at a member holding position close to the installation position in the tunnel radial section, and in that state, is transported to the installation position in the tunnel extension direction along the tunnel extension direction, and installed in the tunnel radial section A precast tunnel construction method comprising a precast member transporting step for moving to a position.   The said precast member is made into the arch formation member which bisects a tunnel radial direction cross section from a perpendicular center axis | shaft, The moving direction by the holding mechanism of the said member conveying apparatus is a substantially up-down direction, The said 1st aspect Precast tunnel construction method. A member transport device used in a precast tunnel construction method in which a protector is provided on a traffic road, and a plurality of precast members are installed above and joined to each other to construct a tunnel.
A travel mechanism capable of traveling above the guide means along the tunnel extending direction provided at the upper part of the protector;
And a holding mechanism that holds the precast member within a predetermined range in a variable position.

Images