JPH0441893A - Measuring device for tail clearance of shield excavator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Application Field) This invention is used to measure the tail clearance of a shield excavator for measuring the gap (tail clearance) between the rear part of the shield main body and the segments assembled along the inner wall of the tunnel. Regarding equipment.

(Prior Art) When excavating a tunnel with a conventional shield machine 5 Every time the shield body excavates one pitch, a segment is assembled along the inner wall of the tunnel excavated by the shield body.

Conventionally, this segment is assembled using a segment erector, but if the center of the shield body is eccentric to the center of the already assembled segment, the tail clearance between the rear of the shield body and the segment will be constant. Otherwise, when assembling the segments, there were cases where the segments interfered with the skin plate of the shield body, making it difficult to assemble the segments.

Particularly in the case of curved construction where the shield body is excavated along a curve, eccentricity between the existing segment and the shield body is likely to occur.

For this reason, various methods and devices for measuring tail clearance have been proposed in the past.

For example, JP-A-63-3157.97, JP-A-62-2
No. 06195, JP-A-62-206196, JP-A-6
3-265098, JP-A-63-171491, JP-A-1-138989, JP-A-1-138990, etc.

(The problem that the invention aims to solve! However, each method and device has problems such as the measuring method or device being complicated or not being able to perform highly accurate measurements.

The present invention has been made to solve these problems, and it is an object of the present invention to provide a tail clearance measuring device for a shield tunneling machine that can easily and accurately measure the tail clearance.

(Means and effects for solving the problem) In order to achieve the above object, the present invention has a plurality of measurement jigs arranged in the circumferential direction inside the shield main body that excavates underground, which can be attached tightly to predetermined locations of the existing segments. At the same time, these measurement jigs are provided with distance sensors for measuring the distance to the skin plate of the shield body.

This allows tail clearance to be measured at multiple locations in the circumferential direction of the shield body, and
By calculating the eccentricity between the shield body and the segment from the obtained tail clearance and controlling the direction of the shield body so that this eccentricity decreases, the tail clearance can be kept constant.

(Example) An embodiment of the present invention will be described in detail with reference to the drawings.

In the figure, reference numeral 1 denotes a shield main body, which is propelled underground by a shield jack 2, and a cutter head 4 rotatably driven by a rad motor 3 to a cutter is provided at the front of the shield main body 1.

The earth and sand excavated by the cutter head 4 is taken into the chamber la from the earth and sand intake port (not shown), is made into a slurry by water injected from the water pipe 5, and is further sent to the rear of the shield body l through the mud removal pipe 6. It is designed to be ejected.

7 is a segment erector for assembling the segment 8 along the inner wall of the tunnel excavated by the shield body l.
Reference numeral 10 denotes a tail clearance measuring device that measures the tail clearance C between the outer peripheral surface of the assembled segment 8 and the inner peripheral surface of the skin plate 1b of the shield body 1.

The tail clearance measuring device 10 is installed at a plurality of locations in the circumferential direction so as to be located between the shield jacks 2, and has a measuring cylinder 11 as shown in FIG.

At the tip of the piston rod 11a that protrudes rearward from the measurement cylinder 11, a measurement jig 12 that tightly fits into the end surface and inner peripheral surface of the segment 8 is rotatably attached via a ball bearing llb. At the same time, a distance sensor 13 such as a laser type or an ultrasonic type is attached to the outer surface of the measurement jig 12 to measure the distance 11y to the skin plate 1b.

Note that 14 in the figure indicates a tail seal.

Next, to explain the operation, when measuring the tail clearance C between the inner circumferential surface of the skin plate 1b of the shield body 1 and the outer circumferential surface of the already assembled segment 8, a plurality of measurement points are provided in one circumferential direction. By extending the measuring cylinder 11, the measuring jig 12 provided at the tip of the piston rod 11a is tightly fitted into the end face and inner peripheral surface of the segment 8, and the distance sensor 13 provided on the measuring jig 12 is used to detect the skin plate 1b. The distance to jl[y is measured at multiple locations 9, for example, at four locations as shown in FIG.

Then, from the measured value y, subtract the distance mx from the distance sensor 13 to the segment outer periphery (a known value that varies depending on the wall thickness of the segment 8 used), and calculate the tail clearance at each position from floor 1 to floor 4 from 01 to c4. Then, calculate the average 4Iic of these tail clearances C, % C, c - (c, 10 c! + c go + c4) and then calculate the eccentricity eX + eF between the center of the shield body 1 and the center of the segment 8.

The horizontal eccentricity eM of the shield body 1 is.

(c c +)cog θ+(c −c *)cos
θe 11. ! Ru.

exl= eI+ ■ e□ 1 + ■ e, □ 1 where e, 1. When ≧O, the shield body 1 is eccentric to the right, and when +<0, it is eccentric to the left.

Similarly, the eccentricity IL of the shield body 1 in the vertical direction is eA11 + 1 e7,1 Here, when eA≧0, the shield body 1 is eccentric upward, and when e, , <Q, it is eccentric downward. t, ゛, eccentricity e
By calculating the amount of eccentricity e as described above, it is possible to determine in which direction the shield body 1 is eccentric with respect to the existing segment 8. By correcting the direction of the shield body 1 so as to correct this eccentricity, the tail clearance C between the shield body 1 and the segment 8 can be made constant.

In addition, if the amount of eccentricity e W + e Y in the up, down, left and right directions is determined and compared every time and the amount of change over the course of 9 hours is determined, it is possible to detect the inclination of the shield body 1 and the segment 8. .

(Effects of the Invention) As described in detail above, the present invention includes measuring jigs provided at multiple locations in the circumferential direction of the shield body in close contact with predetermined positions of the segments, and distance sensors provided on the measuring jigs measuring the distance to the skin plate. Since the amount of eccentricity between the shield body and the segment is determined by measuring the distance, the tail clearance can be maintained constant by controlling the direction of the shield body so that this amount of eccentricity is reduced.

This eliminates problems such as the segment interfering with the skin plate of the shield body, making it difficult to assemble the segment, and the tail clearance can be measured using a distance sensor installed in one measurement jig.
Compared to conventional tail clearance measuring methods and measuring devices, it is possible to measure tail clearance more easily and accurately.

In addition, since the amount of eccentricity can be measured continuously, the inclination of the shield body and segments can also be determined, and by correcting the direction of the shield body based on the obtained data, highly accurate tunnel excavation can be carried out along the construction plan line. is also possible.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is an enlarged view of a tail clearance measuring device, FIG. 2 is a cross-sectional view of a shield tunneling machine, and FIG. 3 is an explanatory view of its operation. 1...Shield body 8...Segment. 13... Distance sensor.

Claims (1)

[Claims] The existing segment 8 is installed inside the shield body 1 that excavates underground.
A shield excavator is provided with a plurality of measurement jigs 12 disposed in the circumferential direction that can be brought into close contact with predetermined locations, and a distance sensor 13 for measuring the distance to the skin plate 1b of the shield body 1 is provided on these measurement jigs 12. tail clearance measuring device.