JPH0696949B2 - Construction method of rectangular section tunnel and shield machine used for it - Google Patents

Description

The present invention relates to a shield construction method and a shield machine.

(Prior Art) Generally, a subway or an underground motorway is constructed mainly by an excavation method or a shield method.

The excavation method is a method of excavating a groove having a box-shaped cross section from the ground surface, constructing an excavation portion in a state where a floorboard is temporarily installed in the opening of the upper surface of the groove, and then backfilling with necessary soil again. This requires enormous cost and time for excavating a groove having a box-shaped cross section from the ground surface as described above, and has a limitation that construction can be done only at night in urban areas. Therefore, the shield method is now widely used.

With this shield construction method, a shield machine equipped with a shield machine equipped with a cutter for excavating earth and sand and a cylindrical shield frame provided on the outer periphery of the shield machine is carried into the ground from a vertical shaft and laterally. This is a method of propelling a tunnel to excavate it and lining a segment on its inner peripheral surface.

(Problems to be Solved by the Invention) However, it is desirable that a building limit of a train, an automobile, or the like is rectangular, and a tunnel for laying a cable or the like is also rectangular in cross section.

However, since the shield construction method has a circular cross section, there is a problem that the construction cost becomes expensive because an unnecessary space must be excavated and an expensive segment is used.

The present invention has been made in view of the above problems, and an object thereof is to provide an inexpensive seal construction method that does not use a segment and an inexpensive seal construction method and a shield machine.

(Means for Solving the Problem) The means for achieving the above object is to provide a circular shield machine having a circular cutter including a circular cutter and a cylindrical frame body with an annular space having a rectangular shape in front view. By excavating a horizontal shaft with a rectangular cross section in the ground by a shield machine with a shield frame detachably attached, by a press jack installed in-situ reinforced concrete cast in the inner peripheral surface of the horizontal shaft The structure is characterized by pressing and lining, and the shield machine is separated and dismantled after the excavation of the side shaft is completed, and the lining is performed with only the shield frame left in the ground. The configuration is characterized by the following.

Further, the shield machine includes a circular shield machine including a circular cutter and a circular frame body, and a shield frame having a rectangular shape in a front view having an annular space detachably installed on the outer periphery of the circular shield machine. The shield frame is formed with a tapered excavation recess at the tip thereof, and the injectors are annularly arranged at appropriate intervals in the excavation recess. It is to be configured.

(Operation) Thus, according to the above configuration, the shield machine loaded from the vertical shaft propels water while jetting water from the jet body inside the tip toward the face to loosen the soil and shaving the loose ground with a cutter. And excavate the side shaft.

Then, lined reinforced concrete on the inner surface of the excavated side pit, lining the site reinforced concrete with a press jack and further pushing the shield machine with the reaction force to build a tunnel. Is to separate and dismantle the shield machine from the shield frame, carry it out to the ground, and divert it to another. The shield frame is left as it is in the ground, that is, at the end of the horizontal shaft on the side of the reaching shaft, and is used as a reinforcing material for the tunnel T. It

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

The shield machine A of the present invention is constructed to construct a tunnel having a box-shaped cross section while being carried into the ground from a vertical shaft and propelled in the lateral direction. The shield machine 1 and a shield frame 2 provided on the outer periphery of the tunnel machine 1 are used. Has been done.

The shield machine 1 is composed of a cylindrical frame body 3 and a cutter 4 provided on the front surface of the frame body 3 in a cylindrical shape.
In this cutter 4, a disc 4c is attached to a rotary shaft 4b protruding from the partition wall 3a, and a cutter bit 4a is attached around a slit 4d provided in the disc 4c. Therefore, the cutter 4 is driven by the motor M to rotate and excavate the natural ground.

The partition wall 3a is provided with a sludge discharge pipe 6a for discharging muddy water and the like excavated by the cutter 4 to the outside of the mine, and a muddy pipe 6b for opposing the earth pressure of the face due to the muddy water pressure.

The mud discharge pipe 6a and the mud feed pipe 6b are provided in the case of the muddy water type, but in the case of the earth pressure type, a screw conveyor is provided instead of the mud discharge pipe 6a to discharge the mud.

Further, a pair of shield jacks 7 arranged in parallel are provided at diagonal positions on the inner peripheral surface of the frame body 3, and the tips of the shield jacks 7 are brought into contact with the mold frame k assembled on the inner surface of the horizontal shaft m. By pushing the frame k, a propulsive reaction force is applied to the shield machine A.

The shield frame 2 has an outer cylinder 2a having a rectangular cross section and a cylindrical inner cylinder.
An annular space 20 is formed between them by being connected to 2b by a connecting piece d.

As shown in FIG. 3, the shield frame 2 is fixed to the outer periphery of the frame body 3 with bolts 2c via a waterproof cushion material.

Further, the shield frame 2 is formed with a tapered excavation recess 9 at the tip thereof, and the excavation recess 9 is provided with an injection nozzle 10a of an injector 10 for injecting water into the natural ground.

Further, press jacks 11 are provided at appropriate intervals in the annular space 20 between the outer cylinder 2a and the inner cylinder 2b of the shield frame 2, and the pressing cylinders 11a are lined on the inner surface of the horizontal shaft m. The reaction force shield machine A is propelled by pressing the reinforced concrete n.

Next, a shield construction method using the shield machine A of the present invention will be described.

First, a shaft for excavating the shield machine A into the ground is excavated, and the shield machine A is assembled and formed in the shaft.

Then, as shown in FIG. 1, the rock is excavated by rotating the cutter 4 while injecting water from the injection nozzle 10a of the injection body 10 at the tip of the shield frame 2 to the face of the face to loosen the rock. The excavated earth and sand becomes muddy water and is discharged from the mud discharge pipe 6a to the rear side (outside the mine). At this time, the press jack 11 is brought into contact with the wall surface of the vertical shaft and presses it, whereby the shield machine A is propelled forward by its reaction force and the horizontal shaft m is excavated. Then, the form k is assembled on the inner peripheral surface of the side pit m, and in-situ reinforced concrete n is placed between them. Next, the shield jack 7 and the press jack 11 are brought into contact with the form k and the cast-in-place reinforced concrete n, and while pushing these, the shield excavator A is further propelled by the reaction force thereof, and these series of operations are repeated. The tunnel T is constructed by.

Finally, after the excavation by the shield machine A is completed, that is, when the reaching shaft is reached, the bolt 2c is removed from the inner surface side of the frame body 3 and the shield machine 1 is disassembled and disassembled. Then, only the shield frame 2 is left in the ground as it is, and the parts other than the shield frame 2 are carried out to the ground. By doing so, the connecting portion between the reaching shaft and the tunnel T can be reinforced without an auxiliary construction method.

(Effects of the Invention) The present invention has the following effects by having the above-mentioned configuration.

On the outer circumference of a circular shield machine including a circular cutter and a cylindrical frame body, a shield shaft having a rectangular shield frame having an annular space in front view is detachably provided to form a horizontal shaft with a rectangular cross section in the ground. There is no wasted space by excavating and lining the cast-in-place reinforced concrete placed on the inner peripheral surface of the side pit with the press jack installed in the annular space, that is, the outer peripheral portion of the circular shield machine. It is possible to construct a tunnel with a rectangular cross section with a lining space made of cast-in-place reinforced concrete.

After the shield machine is separated and dismantled after the excavation of the horizontal shaft, the shield frame alone is left in the ground, that is, by lining the horizontal shaft end on the side of the vertical shaft to reach the vertical shaft. The connection part of can be reinforced without auxiliary construction.

The shield machine can be diverted to another by disassembling and disassembling the shield machine after the excavation of the side shaft and lining the shield frame with the shield frame left in the ground.

The shield machine is composed of a circular shield machine including a circular cutter and a circular frame body, and a shield frame having a rectangular shape in a front view, which is detachably installed on the outer periphery of the circular shield machine and includes an annular space. As a result, the size of the shield frame can be changed, so that a tunnel having a rectangular cross section of an arbitrary size can be constructed.

[Brief description of drawings]

FIG. 1 is a sectional view showing a use state of the shield machine of the present invention, FIG. 2 is a sectional view taken along the line BB of FIG. 1, and FIG.
C line cross section, FIG. 4 is the same DD line cross section, FIG. 5 is the same EE
It is a line sectional view. A: Shield machine, 1: Shield machine 2: Shield frame, 4: Cutter 10: Injector, 11: Press jack m: Side pit n: Cast-in-place reinforced concrete

Claims (4)

[Claims] Claim: What is claimed is: 1. A shield machine having a circular shield machine including a circular cutter and a cylindrical frame, and a shield frame having a rectangular space in front view and having an annular space is detachably provided on the outer periphery of the shield machine. A method for constructing a tunnel having a rectangular cross section, which comprises digging a horizontal shaft, and lining the cast reinforced concrete cast on the inner peripheral surface of the shaft by pressing it with a press jack installed in the annular space. 2. The rectangular cross section according to claim 1, wherein the shield machine is separated and dismantled after the excavation of the side shaft is completed, and lining is performed with only the shield frame left in the ground. Tunnel construction method. 3. A circular shield machine including a circular cutter and a circular frame body, and a shield frame having a rectangular shape in a front view having an annular space removably installed on the outer periphery of the circular shield machine. A shield machine. 4. The shield according to claim 3, wherein the shield frame is formed with a tapered excavation recess at the tip thereof, and the injection body is annularly arranged in the excavation recess at appropriate intervals. Excavator.