JP2620033B2 - Tail clearance measuring device and tail clearance measuring method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tail clearance measuring device and a tail clearance measuring method, and more particularly to a measuring device and a measuring method for measuring a tail clearance of a shield machine during a digging operation in shield tunnel construction.

[0002]

2. Description of the Related Art When a tunnel is constructed by a shield machine, every time the ground is excavated by a predetermined distance, an excavation is made inside a rear end portion of a cylindrical shield skin plate (skin plate) which is an outer peripheral wall of the shield machine. Assemble the segment that will be the inner wall of the tunnel later.

In this case, it is necessary to precisely adjust a minute gap called a tail clearance between the inner surface of the skin plate and the outer surface of the segment to be assembled.
If the segment is fixed without eccentricity between the center of the skin plate and the center of the segment without fine adjustment of this tail clearance, a certain distance will be The interference caused by the eccentricity occurs between the inner surface of the advanced skin plate and the outer surface of the next segment, which makes it difficult to assemble the segment.

Conventionally, there are the following methods for accurately measuring tail clearance. (1) A method of directly reading the tail clearance by applying a ruler between the skin plate and the foremost segment. (2) A method in which the inner diameter of a segment is actually measured by an ultrasonic distance meter or the like, and the tail clearance is calculated from the inner diameter of the shield machine and the thickness of the segment. (3) A method of measuring the opposing tail clearance with a laser distance meter provided on the inner surface of the skin plate.

[0005]

However, the method (1) requires labor for reading and may cause a reading error of a measured value by a measurer. In the method (2), unevenness on the segment surface, The calculation error due to the deformation of the shield machine and the roundness of the segment is large, and the method (3) has various problems such that the rangefinder may be damaged due to impact during assembly of the segment or dirt such as muddy water.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a measuring apparatus and a measuring method capable of easily and directly measuring a tail clearance.

[0007]

In order to achieve the above-mentioned object, a first aspect of the present invention is to provide a support portion and a support portion which is provided on the support portion so as to be extendable and contractible and extend to different predetermined lengths.
And a tail clearance measuring device. According to a second aspect of the present invention, (a) the support portion of the tail clearance measuring device according to claim 1 is installed on a center axis of the shield machine, and until the tips of the two legs contact the skin plate of the shield machine. Expanding the two legs and measuring the angle between the two legs and the central axis;
(B) measuring the angle between the two legs and the central axis by expanding the two legs until the tips of the two legs of the tail clearance measuring device come into contact with a segment; (C) a step of calculating a tail clearance using the angle calculated in the step (a) and the step (c).

[0008]

The tail clearance measuring device includes a support portion and two legs which are provided on the support portion so as to be extendable and contractible and extend to different predetermined lengths, respectively. Is placed on the center axis of the shield machine, and the two legs are spread out until the tips of the two legs touch the skin plate of the shield machine, and the angle between the two legs and the center axis of the shield machine is measured. Spread the two legs until the tips of the two legs of the tail clearance measuring device touch the segment, measure the angle between the two legs and the central axis of the shield machine, and measure the measured angle. Is used to calculate the tail clearance.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic diagram showing a configuration of a main part of a shield machine 1 on which a tail clearance measuring device 11 according to one embodiment of the present invention is mounted. 1, reference numeral 1 denotes a shield machine, 3 denotes a skin plate, 5 denotes a cutter, 7 denotes a jack, 9 denotes a segment, and A denotes a central axis of the shield machine 1. The tail clearance measuring device 11 is attached to a stand (not shown) of the shield machine 1.

FIG. 2 is a view showing the configuration of the tail clearance measuring device 11, and as shown in FIG.
3, legs 15a, 17a, 15b, 17b, 15c, 17
c is attached. At the time of excavating the shield machine and assembling the segments, the legs 15a, 17a, 15b, 17b, 15 contracted as shown in FIG.
c, 17c are directed outward from the support portion 13. Each leg 1
.. Correspond to the supporting portion 13 in FIG.
And the legs 15a, 17a
...... is extendable.

FIG. 2B shows a state in which the legs 15a, 17a... Of the tail clearance measuring device 11 are folded in the horizontal axis direction.

FIG. 2C shows a tail clearance measuring device for actually measuring the tail clearance. Each leg 15a, 17a,... Is opened outward while being extended from the state of FIG.

Next, the tail clearance measuring device 1
The procedure for measuring the tail clearance using No. 1 will be described.

FIG. 3 shows this tail clearance measuring device 1.
FIG. 4 is an explanatory diagram in a case where tail clearance is measured using No. 1. FIG. 4 is a view in the direction of arrow B in FIG.

In FIG. 3A, reference numeral 9 denotes a segment, and A denotes a central axis of the shield machine. 3A, the tail clearance measuring device 11 is in the state of FIG. 2A.
From this state, as shown in FIG.
a are once aligned in the direction of the center axis A of the shield machine 1, and then each leg 15 is moved as shown in FIG. 3 (b) and FIG. 2 (c).
a, 17a... are extended most, and each leg 15a, 17a.
Each leg 15 until the tip of...
a, 17a are opened outward.

FIG. 5 is an explanatory diagram for calculating a distance Y _plate from the center axis A of the shield machine 1 to the skin plate 3. As shown in FIG. 3B, each leg 15a, 17a.
When the tip of ... reaches the skin plate 3, the legs 15
a, 17a... and the central axis A are measured. An angle detection sensor or an encoder is used for measuring the angle.

When the angles θ and φ are measured in this way, the distance Y _plate from the point C at a distance L from the point O of the central axis A to the skin plate 3 is Y = (b sin φ−asin θ) / ( bcos φ−acos θ) · (L−acos θ) + asin θ (1) It is calculated by substituting the measured angle θ and angle φ into (1). Where a is the length of the leg 15a, b is the length of the leg 17a,
a, b, and L are known.

Next, as shown in FIG. 3C, the tips of the legs 15a, 17a... Of the tail clearance measuring device 11 are brought into contact with the surface of the segment 9.

FIG. 6 is an explanatory diagram for calculating the distance Y _seg from the central axis A to the surface of the segment 9 in this state. As shown in FIG. 6, an angle θ and an angle φ between the legs 15a, 17a _,.

When the distance Y _plate and the distance Y _seg are calculated as described above, the segment thickness s is known, so that the tail clearance t can be obtained by t = Y _plate −Y _seg −s.

The legs 15b, 17b and 15c,
Similarly for 17c, the angle θ and the angle φ are measured to determine the tail clearance t, and the average of the calculated tail clearance t is determined.

As described above, in this embodiment, the tail clearance can be easily and directly measured.

The shape and the like of the tail clearance measuring device 11 according to the present embodiment are not limited to those described in the embodiment. For example, in the embodiment, three pairs of legs having different lengths are attached to the support 13. Although provided, the number of legs is not limited to this.

[0024]

As described above, according to the present invention, the tail clearance can be easily and directly measured.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a main part of a shield machine 1.

FIG. 2 is a diagram showing a tail clearance measuring device 11;

FIG. 3 is an explanatory diagram of a case where a tail clearance is measured by a tail clearance measuring device 11;

FIG. 4 is a view in the direction of arrow B in FIG. 3 (b).

FIG. 5 shows the distance Y between the center axis A and the skin plate 3.
Illustration when calculating _plate

FIG. 6 shows the distance Y _seg between the center axis A and the skin plate 3
Explanatory diagram when calculating

[Explanation of symbols]

 1 Shielding machine 3 Skin plate 9 Segment 11 Tail clearance measuring device 15, 17 Leg

Claims (4)

(57) [Claims] 1. A tail clearance measuring device, comprising: a support portion; and two legs provided on the support portion so as to be extendable and contractible and extend to different predetermined lengths. 2. The tail clearance measuring device according to claim 1, wherein a plurality of sets of the two legs are provided on the support portion. (A) installing the supporting portion of the tail clearance measuring device according to claim 1 on a central axis of the shield machine, and keeping the two legs until the tips of the two legs contact the skin plate of the shield machine; Measuring the angle between the two legs and the central axis by spreading the two legs; and (b) measuring the angle until the tips of the two legs of the tail clearance measuring device contact the segment. Measuring the angle between the two legs and the central axis by spreading the two legs; and (c) calculating the tail clearance using the angles calculated in the steps (a) and (c). Performing a tail clearance measurement method. 4. The step (c) includes: calculating a distance Y _plate from the central axis to the skin plate of the shield machine using the angle measured in the step (a); Calculating a distance Y _seg from the central axis to the segment using the measured angle; and calculating a tail clearance t by t = Y _plate −Y _seg −s (s: segment thickness). The tail clearance measuring method according to claim 3, comprising: