JP2575940B2 - Conduit construction method - Google Patents

Description

The present invention relates to a method of constructing a sewer.

[Prior art] Conventionally, as a method of constructing pipes for water supply and sewerage, a synthetic resin pipe is concentrically housed in a tunnel with a primary lining constructed and excavated by a conventional method. It is known to inject and fill mortar M into the gap.

[Problems to be Solved by the Present Invention] One of the objects of the above-mentioned conventional sewer construction method is to use a synthetic resin pipe having a smooth inner peripheral surface to reduce the roughness coefficient and reduce The purpose is to secure a large flow capacity with a pipe with a large area.

However, the conventional culvert construction method requires a joint work space because a flange joint is used for the joint of the synthetic resin pipe, and the difference in the jack for adjusting the position to accommodate the synthetic resin pipe concentrically. The clearance between the inner peripheral surface of the primary lining and the outer peripheral surface of the synthetic resin pipe is 300 to 400 mm (even if the minimum is 22
0mm), which has the drawback that it is necessary to excavate a large-diameter primary-lined tunnel.

In addition, due to the recent rapid changes in social conditions such as urbanization and increased traffic, it is often necessary to build sewers with restricted pipe bottom positions. When the position is constrained, considering the soil covering required for shield construction, the diameter of the primary lining tunnel can not always be secured indefinitely, and there are construction conditions where it is difficult to secure the planned water volume .

[Purpose] Accordingly, the present invention has been made in view of the above, and an object of the present invention is to provide a culvert construction method capable of storing a synthetic resin pipe having a diameter as large as possible in a tunnel with a primary lining having a restricted inner diameter. It is intended.

[Means for Solving the Problems] In accordance with the above objects, the configuration of the present invention having the features set forth in the appended claims, in order to solve the above problems, as a first step, using a shield machine, A tunnel T, which has been primarily lining with the segment ring 2 in a conventional manner, is constructed. As a second step, a pair of rails 3 parallel to the axial direction is laid at the bottom of the tunnel T. On the carry-in truck 4 guided and moved by the rail 3, the enlarged diameter portion 5a is provided on the inner peripheral side at one of the front and rear ends, and the waterproof property is provided via the packing 6 in the enlarged diameter portion 5a on the outer peripheral side at the other front and rear ends. A synthetic resin tube 5 having a predetermined length having a reduced diameter portion 5b large enough to be held and inserted is mounted, and the synthetic resin tube 5 is carried into a predetermined position in the tunnel T. As a fourth step, the synthetic resin tube 5 is used. Rail 3 below tube 5
Air jacks 7, 7 having a plurality of air jack elements 7a, 7b in the axial direction of the tunnel are inserted into the left and right sides of the car, and air is press-fitted into each of the air jack elements 7a, 7b to carry the synthetic resin pipe 5 into the carriage. 4 to take out the carry-in carriage 4 and adjust the amount of pressurized air to adjust the axis of the synthetic resin pipe 5 to the tunnel axis. As a fifth step, a position holding support is provided below the synthetic resin pipe 5. .. Are arranged, the air in each of the air jack elements 7a, 7b is evacuated, and the air jacks 7, 7 are taken out. The synthetic resin pipe 5 is fixed by arranging a floating prevention U-band 9 to be fixed to the segment ring. As a sixth step, the segment ring 2 and the synthetic resin pipe 5 are fixed.
And technical means for injecting the mortar M into the gap between them.

[Operation] Therefore, in the duct construction method of the present invention, the primary lining tunnel T is constructed in the first step, and the rail 3 is laid in the second step as in the conventional method. The synthetic resin pipe 5 carried in the three steps is provided with water-tightness through the packing 6 in the large-diameter portion 5a on the inner peripheral side at one of the front and rear ends and the above-mentioned large-diameter portion 5a on the outer peripheral side at the other front and rear ends. .., Which are successively carried in, become a socket joint, exhibiting an action capable of being processed within the thickness of the synthetic resin pipe 5, and having an inner periphery. When the outer diameter-side reduced diameter portion 5b is inserted into the side diameter-increased portion 5a, an appropriate clearance is set at a portion other than the packing 6 so that the curved portion of the tunnel T can be dealt with.

Also, the air jack 7 used in the fourth step is very thin and can secure a sufficient stroke, unlike a normal jack, and the minimum synthetic resin pipe 5 is supported at four points by the air jack elements 7a and 7b. Since the position adjustment of the synthetic resin tube 5 can be easily and reliably performed, and a pressure-resistant hose for pressurizing air can be connected to each of the air jack elements 7a and 7b, it is necessary to use a narrow space. It has the effect of being released from jack operation. In the present application, the reason why the synthetic resin tube 5 is floated from the carry-in vehicle 4 is to take out the carry-in vehicle 4, so that the synthetic resin tube 5 does not necessarily need to float reliably, and the own weight of the synthetic resin tube 5 is applied to the carry-in vehicle 4. It is possible to prevent the carry-in cart 4 from being pulled out with a large force by preventing the carrier from being applied.

Further, prior to the sixth step, in the fifth step, the synthetic resin pipe 5 is fixed with supports 8, 8, 8,... This has the effect of reliably preventing displacement due to generation of buoyancy by injection.

Embodiment Next, an embodiment of the present invention will be described below with reference to the accompanying drawings.

As a first step, a tunnel T whose primary lining is formed by the segment ring 2 by a conventional method is constructed using a shield machine.

Of course, this first step is performed by various conventional methods, but as described above, there is a restriction on the pipe bottom position, and when the soil cover is shallow, it is necessary to perform accurate earth pressure management.
In the present embodiment, the bubble shield method was employed, and the fluctuation of the face pressure was reduced by the compressibility of the bubbles, and the excavated soil was improved in fluidity and water stoppage, and the excavation was performed stably without disturbing the face.

In the present embodiment, the specifications of the shield machine (not shown) are as follows in order to minimize the sinking and rising of the shield machine and improve the finishing accuracy of the primary lining tunnel T.

a. Face plate configuration 1. In order to take in the earth pressure evenly, a 4-spoke type was used, eliminating the problem of ingestion of excavated soil at the outer periphery.

2. A shape with a large slit width was adopted in consideration of the transmission of the face earth pressure into the chamber, and the aperture ratio was 38.6%.

3. A face plate structure was adopted in consideration of face holding during stoppage and emergency.

b. Configuration of the bubble discharge port 1. Four bubble discharge ports were provided on the entire surface of the cutter spoke so that the bubble material was uniformly distributed in the chamber.

2. In order to reduce the discharge resistance of excavated soil, two bubble discharge ports were provided on the side of the screw conveyor casing, and the bubble material was injected into the screw conveyor.

3. Three air outlets are provided at the top of the shield machine.
Discharge the foam material toward the face crown, use the foam material as a lubricant between the shield machine and the ground, and
The bubble discharge port also served as a chemical liquid injection hole for the face collapse.

In addition, in this embodiment, at the time of backfilling, a grout hole usually provided at the center of the segment is provided shifted to the rear side of the excavation to measure the early filling of grout, and grout injection is performed on both sides of the injection pressure and the injection amount. Managed from.

Further, in the present embodiment, the digging direction is controlled by using a gyrocompass at the time of excavating the shield, horizontal and vertical meandering are minimized as much as possible, and sufficient excavation accuracy is obtained in the subsequent steps. The outer diameter of the segment ring 2 constructed in the first step was 3810 mm, and the effective space diameter for the secondary lining was 3554 mm.

In the second step of the present invention, a pair of rails 3 parallel to the axial direction is laid at the bottom of the tunnel T. The rail 3 may be a conventionally known one. In this embodiment, the rail 3 is welded and fixed to the segment ring 2 using a 90 × 90 mm angle material with a rail gauge of 762 mm.

Next, as a third step, the diameter of the enlarged diameter portion is set on the inner peripheral side at one of the front and rear ends on the carry-in truck 4 guided and moved by the rail 3.
Packing 6a in the enlarged diameter portion 5a on the outer peripheral side of the front and rear other ends.
A synthetic resin pipe 5 of a predetermined length having a reduced diameter portion 5b that can be inserted while maintaining water-stopping is mounted, and the synthetic resin pipe 5 is carried into a predetermined position in the tunnel T.

The synthetic resin pipe 5 has an effective space diameter of the primary lining tunnel T constructed in the first step of 3554 mm, whereas an FRP-M pipe (hard vinyl chloride pipe) having an outer diameter of 3328 mm (inner diameter of 3200 mm). ), 110m left and right in calculation
will have m spaces. But actually,
Lighting equipment, power equipment, mortar M
The space that can be used is very limited due to the presence of the injection tube and the like.

Therefore, in this embodiment, as shown most clearly in FIGS. 6 and 7, an ultra-thin carry-in cart 4 is prepared. That is, the carry-in cart 4 has horizontal rolling support shafts 42 projecting from four corners of the frame 41, respectively, and the rolling support shaft 42 is provided with a bearing 43 on the side of the frame 41 via the bearing 43. 44 is rotatably supported. 45 is a frame by the vertical axis 46
Side rollers are rotatably supported by 41, and the side rollers 45 roll along the inner side surface of the rail 3 so that derailment is prevented. Reference numeral 47 denotes a support plate for the synthetic resin pipe 5, and reference numeral 48 denotes a connection hole with a battery locomotive (not shown) that allows the carry-in cart 4 to run. In addition, the carry-in cart 4 is provided with a rolling wheel 44 supported on a horizontal rolling support shaft 42 on the side of the frame 41 to make it thinner. In addition, the aforementioned rail gauge is set to a minimum, and The central portion of 41 is curved concavely in accordance with the curvature of the peripheral surface of the synthetic resin tube 5 so that the synthetic resin tube 5 can be carried in a narrow space. Further, the synthetic resin pipe 5 has an inner diameter-increased portion 5a on one of the front and rear ends and an outer diameter-reduced portion 5b on the other front and rear sides, and has a thickness of 64 mm, which is the thickness of the synthetic resin pipe 5. Working within the range, the outer diameter of the joint part was made the same as that of the general part to facilitate installation in a narrow space, and the joint part was provided with a clearance capable of coping with the curved part. The synthetic resin tube 5 is 4000 mm
The weight was 5250 Kg using the length. Also,
It is a matter of course that a material that can withstand the pressure when the mortar M is injected is used as the packing 6.

When the synthetic resin pipe 5 is carried in, if the existing synthetic resin pipe 5 is already located in front of the carry-in, the newly introduced synthetic resin pipe 5 has its front end behind the existing synthetic resin pipe 5. Either position immediately after the end and push it into the final installation position later,
And the other end side of the front and rear sides and the reduced diameter portion 5b on the outer peripheral side may be inserted into the final installation position where they are inserted into each other. It was brought to the installation position.

Then, as a fourth step, an air jack 7,7 having a plurality of air jack elements 7a, 7b in the tunnel axial direction on the left and right sides of the rail 3 below the synthetic resin pipe 5 is provided.
And press-fit air into each of the air jack elements 7a and 7b to lift the synthetic resin tube 5 from the carry-in vehicle 4 to take out the carry-in vehicle 4 and adjust the amount of air press-in to adjust the axis of the synthetic resin tube 5 Align with the tunnel axis. The air jacks 7, 7 need to be ultra-thin as well as the above-described carry-in cart 4, and a normal hydraulic jack having a large loading load cannot be inserted below the synthetic resin pipe 5. Further, since it is difficult to work in a narrow space with a normal mechanical jack, an ultra-thin air jack 7 was prepared as shown most clearly in FIGS. 8 and 9. In other words, the air jack 7 is configured such that a tire 72 fitted on a wheel 72 is stored in a sideways manner in both ends of a rectangular receiving box 71 having an upper opening, and the jack elements 7a, 7b
The side face of the tire 73 facing upward is used as a load receiving surface directly or via a mount plate (not shown). And, although not always clear from the figure,
The tire 73 is provided with a pressure-resistant hose connection port, and this pressure-resistant hose has a sweep-out port for a pressure air supply source (not shown),
A switching valve or the like that can be separately switched to the exhaust port is provided so that the amount of press-fit air in each of the jack elements 7a and 7b can be adjusted. Outer diameter as a specific example
When a tire 73 of 450 mm and 6 ply strength was used, the stroke was 5 to 17 cm, and the loading capacity was 3 t per jack element. If the front end of the synthetic resin tube 5 is inserted into the rear end of the existing synthetic resin tube 5, it is impossible to lift the synthetic resin tube 5 from the carry-in cart 4 without limit, but the above-described simulation is performed. As described above, this floating does not necessarily mean that there is a need to create a space between the synthetic resin pipe 5 and the carry-in carriage 4, and that the rear end side of the new synthetic resin pipe 5 (the start end of import).
It is also possible to take out the carry-in cart 4 by making the 大 き く rise large. In FIG. 8, reference numeral 74 denotes a handle bar.

Then, as a fifth step, supports 8, 8, 8... For holding the position are arranged below the synthetic resin pipe 5, and the air in each of the air jack elements 7a, 7b is evacuated. 7
At the same time, the synthetic resin pipe 5 is fixed by disposing a floating preventing U-band 9 for fixing both ends to the lower part of the segment ring 2 on the synthetic resin pipe 5.

The U band 9 is made of flat steel or the like, and both ends thereof are welded and fixed to the lower part of the segment ring 2 to sufficiently fix the band.

Then, as a sixth step, mortar M is injected into the gap between the segment ring 2 and the synthetic resin tube 5.

For the injection of the mortar M, a rigid vinyl chloride pipe having a diameter of 40 mm was used as an injection pipe, and clay sand air mortar was injected from a conventionally known mortar pumping device (not shown). When the mortar M is injected, there is no need to worry about displacement because the synthetic resin tube 5 is sufficiently fixed.
Since there is a possibility of deformation of the synthetic resin tube 5 due to buoyancy, the lower injection and the upper injection were performed at a predetermined time interval.

[Effects of the Invention] Since the present invention is as described above, the gap between the segment ring 2 and the synthetic resin pipe 5 can be greatly reduced as compared with the prior art. This is specifically described with reference to FIG. In the example of construction using half the conventional maximum pipe, the inner diameter of the synthetic resin pipe 5 was 3000 mm and the gap between the segment ring 2 and the synthetic resin pipe 5 was 220 mm. It became possible to make 3200mm. That is, the method of the present invention has an effect that the limited space by the shield method can be used as effectively as possible.

In addition, the present invention has a method of constructing a sewer system in which the gap between the segment ring 2 and the synthetic resin pipe 5 can be greatly reduced, so that the loss of the effective area responsibilities is small, and the gap can be reduced for economical construction. That can be provided.

Further, the present invention achieves not only the original purpose of securing a large flow capacity by reducing the roughness diameter by using the synthetic resin pipe 5, but also the economical construction with a small loss of the effective area responsibility. The effect and the effect of preventing water leakage, improving durability, and improving corrosion resistance by using the synthetic resin pipe 5 are synergistic, so that not only water and sewage pipes but also general tunnels, especially large depths that will be required in the near future This can have a remarkable effect on tunnel construction.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a tunnel constructed by the first step of the method of the present invention, FIG. 2 is a cross-sectional view of a main part in a state of steps 2 to 3, and FIG. 3 is a fourth to fifth steps. FIG. 4 is a cross-sectional view of a main part in a fifth step, FIG. 5 is a partial cross-sectional view of a synthetic resin pipe used in the present invention, and FIG. 6 is a cross-sectional view of the present invention. Plan view of the loading cart used,
FIG. 7 is an enlarged sectional view taken along the line AA, FIG. 8 is a plan view of the air jack used in the present invention, FIG. 9 is an enlarged sectional view taken along the line BB, and FIG. It is sectional drawing which shows the sewer constructed in half by the method of this invention. 2-segment ring, 3-rail 4-carry-in trolley, 5-synthetic resin pipe, 5a-expanded part, 5b-reduced diameter part 6-packing 7-air jack, 7a, 7b-air jack element, 8-support , 9-U band, T-tunnel, M-mortar

Continued on the front page (72) Inventor Tsutomu Nita 4-57-506 Senriyama Higashi, Suita-shi, Osaka (72) Inventor Kinsaburo Nukata 2-3-14, Tokuan, Tsurumi-ku, Osaka-shi, Osaka (72) Inventor Kinya Kunimasa Osaka (21) Inventor Makoto Nakamura 1-29, Oganecho, Nishi-ku, Nagoya-shi, Aichi (56) References JP-A-1-284699 (JP, A) JP-A-63-63899 (JP) , A) JP-A-49-83229 (JP, A)

Claims (1)

(57) [Claims] 1. A first step is to construct a tunnel T which is firstly wrapped with a segment ring 2 by a conventional method using a shield machine, and a second step is to attach a shaft to the bottom of the tunnel T The third step is to lay a pair of rails 3 parallel to the direction. As a third step, on the carry-in truck 4 guided and moved by the rails 3, the enlarged diameter portion 5 a is provided on the inner peripheral side at one end in the front and rear, and A predetermined length of the synthetic resin pipe 5 having a reduced diameter portion 5b of a size that can be inserted into the above-mentioned enlarged diameter portion 5a through the packing 6 while maintaining the water blocking property is mounted on the outer peripheral side, and is positioned at a predetermined position in the tunnel T. In the fourth step, the air jack 7, which has a plurality of air jack elements 7a, 7b in the tunnel axial direction on the left and right sides of the rail 3 below the synthetic resin pipe 5, Insert 7,
Air is injected into each of the air jack elements 7a and 7b to lift the synthetic resin tube 5 from the carry-in vehicle 4 to take out the carry-in vehicle 4, and adjust the amount of air press-in to adjust the synthetic resin tube 5
Are aligned with the tunnel axis. As a fifth step, supports 8, 8, 8... For holding the position are arranged below the synthetic resin pipe 5, and the air jack elements 7a, 7b While removing air, take out the air jacks 7,7, and place a floating prevention U-band 9 on both ends of the synthetic resin pipe 5 to fix both ends to the lower part of the segment ring 2, and fix the synthetic resin pipe 5, A culvert construction method in which mortar M is injected into the gap between the segment ring 2 and the synthetic resin pipe 5 as six steps.