JPS62151706A - Detector and method for displacement measurement in tunnel inner section - Google Patents

Abstract

PURPOSE:To detect displacement, etc., between a necessary reference point and adjacent position to be measured accurately by arranging plural displacement measuring instruments according to the properties of the measurement section of a tunnel inner section. CONSTITUTION:Displacement detectors 10 are fixed 12 at positions M1-M5 to be measured at intervals L1-L5 from the reference position M0 on a tunnel inner wall 3. Then, one end of a wire 19 extended among the respective detectors 10 is fixed at the position M0 and the other end is extended to nearby the position M5 at the terminal to couple and suspend a weight 29. Consequently, constant tension is applied to respective parts of the wire 19. Assuming that, for example, the point M1 is displaced vertically in this state, the detector 10 is also displaced, so a displacement measuring pulley 13 rotates counterclockwise and angle transmission arms 15 and 16 rotate slightly clockwise and counterclockwise respectively. Variation in the relative rotation angle (relative angle) of the pulley 13 (arms 15 and 16) to the detector body 11 is detected by a displacement gauge 14 (goniometers 17 and 18), which outputs an electric signal corresponding to the displacement of the section L1 (relative angle variation between sections L1 and L2).

Description

Detailed Description of the Invention (a) Technical Field The present invention relates to a displacement measurement detector installed on the inner wall of a tunnel to measure the displacement situation inside the tunnel, and This relates to a method for measuring displacement in the sky.

(b) Prior art A tunnel that is drilled by excavating bedrock, etc. has a deformed cross-sectional form of its inner peripheral wall due to the hardness or softness of the rock or changes in the soil, and this is called ``inner space displacement.'') In extreme cases, there is a risk of cave-ins. Therefore, when measuring the displacement inside a tunnel (especially a tunnel using the NATM construction method), it is difficult to measure the displacement inside the pile! This is considered a daily measurement item (Measurement A) along with inspection surveys and crown settlement measurements.

Conventionally, such internal space displacement measurement has been carried out manually using a convergence measure.

FIG. 6 is a front view showing a schematic configuration for explaining this conventional internal space displacement measuring method.

In the figure, reference numerals 1 and 2 are convergence bolts implanted in opposing parts of the tunnel inner wall 3 with their axial directions aligned, and one end of the tape 5 is connected to one convergence bolt 1 via a unit 4. are connected, and the other end of this tape 5 is connected to a tension device 6 with an adjustment tube,
It is connected to the other convergence bolt 2 via the dial gauge 7 and the unit 8 in order, thereby forming a so-called convergence measure.

When measuring internal displacement, two units 4 and 8 of the convergence measure are attached to both convergence bolts 1 and 2.

Adjustment device 6 to more accurately measure the distance between two points
Adjust the tension of the tape 5 to be constant by operating . Thereafter, the value on the dial gauge 7 is read and recorded. After an appropriate time or a predetermined time has elapsed, the tension of the tape is adjusted and the value of the dial gauge 7 or the change from the initially read value is recorded. Thereafter, the distance (or length) between the opposing tunnel inner walls 3 and 3 is determined by the same procedure.
Measure changes in

By the way, such a conventional method for measuring internal space displacement requires extensive work for installation, adjustment (including calibration) work, measurement work, etc. because the convergence measure is installed across the tunnel interior. Scaffolding must be erected using heavy machinery and by skilled workers, which is not only very costly, but also involves the danger of working at heights. Furthermore, there was the inconvenience that construction work such as tunnel excavation work and earth and sand transport work had to be interrupted each time installation work or measurement work was performed.

Furthermore, it requires skill to install the equipment and it is necessary to apply accurate tension to the tape 5.Furthermore, in order to improve measurement accuracy, convergence measure units 4 and 8 and dial gauge 7 are attached for each measurement. However, there is a downside in that it involves extremely troublesome work, such as the need to calibrate using a calibration device.

In addition, since the dial gauge 7 is for visual inspection,
Not only does it have the disadvantage of large reading errors, but it also has the disadvantage of not being able to transmit measurement data electrically, making it impossible to measure at a remote location, and requiring manual calculations. There is.

Furthermore, in recent years, the importance of construction management has increased, and prompt feedback of measurement data to the site is required, and the development of internal space displacement measurement methods that provide electrical output and equipment that realizes this method is required. Although there is a demand for this, it is impossible to meet that demand with mechanical measurements such as the above-mentioned convergence measure.

(c) Purpose The present invention was made in view of the above-mentioned conventional electric point,
The purpose of this is to easily and easily convert displacements and relative angles between reference points or adjacent points to be measured into electrical signals, which are necessary to know the displacement status at points to be measured in various tunnels or structures. To provide a detector for measuring displacement inside a tunnel that can detect accurately, has a simple configuration, is inexpensive to manufacture, can be reused many times, and has excellent portability. , this measurement can be performed at a point far from the point to be measured, there is no danger from working at heights, no skill is required, installation costs and measurement costs are low, and there is no need to interrupt construction work. Moreover, it is an object of the present invention to provide a method for measuring the displacement of the tunnel interior, which can measure the displacement of the tunnel interior with good accuracy.

(d) Configuration The first invention (invention set forth in claim 1) is:
In order to achieve the above purpose, a detector body is fixed to a measurement point on the inner wall of the tunnel by an anchor means, a pulley is rotatably supported on the detector body, and a pulley is hung on the pulley and is attached to both ends. a wire to which a predetermined tension is applied; a displacement measuring converter provided on the detector body that detects the amount of rotation of the pulley with respect to the detector body and outputs an electrical signal corresponding to the amount of rotation; It consists of first and second relative angle measuring converters that are provided on the detector body and detect the drawing direction angle of each end of the wire with respect to the detector body, and output electric signals corresponding to the angles. , characterized in that it is configured to obtain an electrical signal corresponding to the section displacement and relative angle between adjacent measured points or reference points necessary for grasping the cross-sectional form of the tunnel interior. , the second invention (the invention set forth in claim 2) is a detector body having an anchor means, a rotatable pulley, and a displacement measurement device that detects the amount of rotation of the pulley and outputs an electric signal. A displacement measurement detector, in which a first and second relative angle measurement transducer are respectively attached, each of which detects the pull-out direction angle of each end of the wire stretched over the pulley with respect to the detector body. are installed with the anchor means at a plurality of measurement points on the tunnel inner wall, one end of one of the wires is fixed to a reference point on the tunnel inner wall, and the wire is connected to one of the plurality of displacement measurement detectors. A tension applying means is connected to each pulley in turn to apply a constant tension to the other end, and the displacement measuring transducer and the first
, each displacement measurement from the reference point based on the electric signal corresponding to the displacement and relative angle of the measurement point with respect to the adjacent measurement point or the reference point, respectively output from the second relative angle measurement converter. This feature is characterized in that the position coordinates of the detector are calculated.

Hereinafter, the configurations of the first and second inventions (herein, both inventions may be collectively referred to as the present invention) will be described in detail based on embodiments shown in the accompanying drawings.

FIG. 2 is a front view showing the configuration of an embodiment of the first invention.

In the figure, reference numeral 9 is tunnel lining concrete, which is used to stop earth and sand and rocks from falling and spring water after excavating bedrock, and its inner surface forms the tunnel inner wall 3. .

Reference numeral 10 denotes a displacement measurement detector (hereinafter abbreviated as "displacement detector") for measuring the displacement of the tunnel inner wall, and its basic configuration includes a detector main body 11, an anchor jig 12 as an anchor means. , a displacement measurement pulley 13, a displacement meter 14 as a displacement measurement transducer, first and second angle transmission arms 15 and 16. It consists of angle meters 17 and 18 as first and second relative angle measuring converters, and a wire 19. Among these, the detector main body 11 has a heptagonal but plate-like shape similar to the shape of a baseball home base, and an anchor jig 12 is attached to one end by means of welding, screwing, etc. The detector main body 11 is fixed by planting an anchor jig 12 into the tunnel lining concrete 9 forming the tunnel inner wall 3. A main body of a displacement meter 14 as a transducer for measuring displacement is attached to this detector body 11, and a rotating shaft 14a serving as a sensing portion of this displacement meter 14 or a rotating shaft concentric with this rotating shaft 14a is attached. A displacement measurement pulley 13 is fitted and fixed to a support shaft (not shown in the figure) that rotates integrally. In this embodiment, a potentiometer is used as the displacement meter 14. Detector body 1
At equidistant positions on both diagonal sides of the pulley 13 on 1,
The main bodies of angle meters 17 and 18, each consisting of a potentiometer as a first and second relative angle measuring transducer, are attached, while rotating shafts 17a and 18a as sensing parts of these angle meters 17 and 18 are attached. Alternatively, the proximal ends of the first and second angle transmitting arms 15 and 16 are attached so as to rotate together by a support shaft that rotates together with this. These elongated plate-shaped first and second
Three pulleys 21, 22, 23 and 24, 25.degree. 26 are rotatably attached to the angle transmission arms 15 and 16, respectively, substantially linearly in the longitudinal direction. Guide pulleys 27 and 28 are rotatably mounted on the detector main body 10 between the rotation shafts 17a and 14a and the rotation shafts 18a and 14a. A wire 19 made of an invar wire is connected to the pulleys 21 and 22 in the displacement detector lO.
．． 23 in a staggered manner, and then guide pulley 2
7. It is pulled out via the displacement measurement pulley 13, the guide pulley 28, and further over the pulleys 24, 25, and 26 in a staggered manner.

FIG. 1 is a schematic sectional view for explaining an embodiment of the second invention.

In the figure, to, 10, . . . are displacement detectors for measuring the displacement inside the tunnel shown in FIG. 2, and represent the properties of the measurement cross section of the inside of the tunnel.

The required number is placed at predetermined intervals depending on the measurement purpose, measurement location, etc. In this example, there are six locations to be measured.
Six displacement detectors 10 are also provided. Reference numeral 19 denotes a wire made of an invar wire, one end of which is fixed to the reference point Mo, and is successively stretched around each displacement detector 10 as shown in the embodiment of FIG. 2, and the other end is A weight 29 is connected near the last measured point M5 and is configured to apply a constant tension.

Next, the operation of the embodiment configured as described above will be explained.

First, in a predetermined section of the tunnel inner wall, the reference point Mo
And sections L1 to L5 are provided from this reference point Mo to the measured points M1 to M5.

Each displacement detector 10 is fixed by each anchor jig 12. Then, one end of the wire 19 that is stretched around each displacement detector 10 is fixed to the reference point MO, and the other end of the wire 19 is extended to the vicinity of the end point to be measured M5, and a weight 29 is connected and suspended. As a result, a constant tension is always applied to each part of the wire 19. In such a state, for example, if it is assumed that the measurement point M1 has subsided (displaced) in the vertical direction, the displacement detector 10 has also subsided, so the displacement measurement pulley 13 rotates counterclockwise. At the same time, the first angle transmission arm 15 rotates slightly clockwise, and the second angle transmission arm 16 rotates slightly counterclockwise. The displacement meter 14 detects a change in the relative rotation angle of the displacement measurement pulley 13 with respect to the detector main body 11, and an electric signal corresponding to the rotation angle, in other words, 1
An electrical signal corresponding to the displacement (in this case, negative displacement) in section L1 is output. Further, the angle meters 17 and 18 detect the relative angle changes of the first and second angle transmission arms 15 and 16 with respect to the detector main body 11, respectively, and the electric signals corresponding to the relative angle changes, in other words, the adjacent An electrical signal corresponding to a relative angle change (in this case, a positive angle change) between the sections L1 and L2 is output.

FIGS. 3A and 3B are explanatory diagrams for explaining the principle of detecting relative angle changes in adjacent sections.

In the same figure (a), the relative angle formed by the wires 191 and 192 stretched between the adjacent measurement point and the measurement point is θ, and two lines that intersect the wire 191 and 192 at an arbitrary angle La and Lb, and these line segments La
And the angle at which Lb intersects wires 19+ and 192 is A+.

A2 and B1. When B2 is assumed, the relative angle θ has the following relationship.

θ=As +A2-180"...(1) θ=B
! +Bz-180° (2) This relationship also holds true when the relative angle θ is larger than the above case, as shown in FIG. 3 (b). From this, no matter what angle the displacement detector main body 11 is attached to the lining concrete 9, if the angles At, A2 or Bl, B2 are known, the relative angle is 0 from the above equation (1) or (2). I understand that this is required.

Figures 4 (a), (b), and (c) are diagrams for explaining the measurement principle of the tunnel interior displacement, respectively, and the same figure (a) shows that a subsidence of ΔX has occurred toward the center of the tunnel. When,
The same figure (b) shows that when a movement of ΔX occurs in the lateral direction,
FIG. 3C is a diagram schematically showing a state when the sinking of ΔX and the lateral movement of ΔX occur simultaneously.

Now, if the initial installation relative angle at any measured point Mi is θ, and the length (section distance between adjacent displacement detectors) is Qi and Qi-t, respectively, then the amount of movement (conversion amount) of the measured point Mi is , Mi−+ to Mi+x angle and Qi,
It can be determined by measuring the amount of change in the length of Qi-+.

That is, for example, the initial section distance Q is 2000 m+.

Assuming that the initial relative angle is 150° and the amount of movement ΔX at the measured point Mi, the downward direction is 51111 in the case of Fig. 4 (A).
．． Assuming that there was a movement of 5 m in the left lateral direction in case (b) and 511 m1 in the downward and left lateral direction in case (c), the section displacement Q1-1°Qi in each case, the measured point M
Relative angle θ1 at it, Mi, Mint
-1. θi and θi+1 change as shown in the table below. (Unit of displacement: m, unit of angle: degrees).

2, displacement meter 1 at adjacent measurement points MiyMi÷1
If the observed values according to 4 are Li and Lif+, the respective interval displacements Ωi are as follows: Qi = Li++ -Li ・Old...
Given in (3). These are the numbers in parentheses in the table above.

In this way, each measurement point MO...Mi...M
The values of the relative angle θ and the section displacement Q at n can be known.

FIG. 5 is a block diagram showing the configuration of an embodiment of the tunnel interior displacement measuring device.

In the same figure, 10a, 10z, 10i, -10n
is the displacement detector shown in FIG. 2, and each output value ΔE
o, ΔEt, ΔEi...ΔEn.

It is transmitted to the scanner 30 via the connection cable. The scanner 30 sequentially inputs each output value ΔEo, ΔEi, . Arithmetic unit 3
1 is data supplied by the initial data setter 32;
and each of the above output values ΔEo, ΔEl, ΔEi...ΔE
The position coordinates of each displacement detector are calculated based on n, and the coordinate value signals are sequentially output to the buffer 33. buffer 3
The coordinate value signal outputted to 3 is outputted to an X-Y plotter 34, and the position of each displacement detector is plotted by this X-Y plotter 34, respectively. These plurality of displacement detectors are installed along the inner wall of the tunnel that forms the outline of the tunnel interior, so the X-Y plotter 34 plots the plotted points or connects these points in sequence. The cross-sectional form of the tunnel interior can be understood from the diagram, and ground subsidence, cave-ins, etc. can be predicted from changes in that form.

Recently, by using microcomputers,
Coordinate values can be easily calculated.

By transferring this to the X-Y plotter 34, graphic processing can be instantaneously performed, which greatly contributes to construction management.

The tunnel interior displacement detector according to this embodiment, which is configured and operates as described above, has a basic configuration of the detector main body 1.
1, anchor jig 12, displacement measurement pulley 13, displacement meter 1
4. 1st. Second angle transmission arms 15, 16. Angle meter 1
Since it has a simple configuration consisting of 7, 18 and wire 19,
In addition to being highly portable, the manufacturing cost is low, and the installation work is simple: attaching the anchor jig 12 to the tunnel lining concrete 9.
It has the advantage that it can be installed and removed, it can be reused, and it can be installed in any order since it only needs to be implanted.

In addition, this displacement detector can obtain electrical signals according to displacement and angle, so remote measurement, quick feedback to the measurement site, automatic calculation processing and graphic processing using a microcomputer, etc. are possible, and visual measurement is possible. On the other hand, there is no room for reading errors to occur, and the need for manual calculations can be eliminated, which improves measurement accuracy. Furthermore, since a constant tension is always applied to the wire 19 by a single weight 29, handling is easy, as there is no need to adjust the tension each time the measurement is made, unlike in the conventional inner space displacement measurement method. , no skill is required for measurement work.

Also, to detect the angle at which the wire 19 is stretched.

Since the two angle meters 17 and 18 and the angle transmission arms 15 and 16 are provided, there are no restrictions on the mounting posture of the displacement detector 10 with respect to the tunnel inner wall 3, and a certain level of accuracy can be ensured.

Furthermore, according to the embodiment shown in FIG. 1, the plurality of displacement detectors 10, 10..., the wire 19, and the weight 29 are all arranged along the tunnel inner wall 3, so that the conventional convergence measure There is no obstacle to cross the tunnel, so there is no need to interrupt the construction work. In addition, since there is no need to climb to a high place for measurement, there is no danger and no skill is required, and installation costs and measurement costs can be significantly reduced compared to conventional methods.

Furthermore, the electric signal output from each displacement detector 10 is
For example, by processing with the tunnel interior displacement measuring device shown in FIG. 5, the condition of the tunnel interior can be quickly and accurately known, and extremely convenient information can be obtained for construction management. Using this information, the detection accuracy can be easily improved by increasing the number of displacement detectors and reducing the distance per section.

It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

For example, in the embodiment described above, the detector main body 11 and the anchor jig 12 are fixed unrotatably, but the third
As is clear from the description of the figures, both of these may be configured to be able to rotate relative to each other around the rotation axis 14a.

Also, 1st. The second angle transmitting arm 15° 16 and the pulleys 21 to 26 attached thereto are not essential, and the point is that the wire 19 can be pulled out from the displacement detector 10 in the direction in which both ends of the wire 19 are pulled out. For example, one end of the sensing lever rotates around the rotation shaft 17a or 18a, and a sensing pin (a roller may be used) is provided at the other end of the sensing lever, so that this pin always comes into contact with the wire 19. The sensing lever may be biased by a spring as shown in FIG.

Also, this sensing lever or the first. The pivot point of the second angle transmission arm 15.16 is not limited to the position shown in the second diagram,
For example, as far as layout constraints permit, the displacement measuring pulley 13
The location may be close to . And guide pulley 27.
28 may be omitted.

Furthermore, an example in which a potentiometer-type displacement meter and an angle meter were used as the displacement measurement converter and the first relative angle measurement converter was explained, but a rotary encoder,
Alternatively, a strain gauge-type angle meter or displacement meter may be used.In short, as long as it is a converter that detects the amount of rotation (rotation angle) and outputs an electric signal corresponding to the amount of rotation, the type 1
It does not matter the type or structure.

(e) Effects As detailed above, according to the first invention, the displacement between the reference point or the adjacent measured point necessary for knowing the displacement situation at the measured point of a tunnel or various structures. It is easy to obtain electrical signals that accurately correspond to angles and relative angles, and the configuration is simple and manufacturing costs are low.
Easy to install, take down, and handle, and can be reused many times.
In addition, it is possible to provide a detector for measuring displacement inside a tunnel that is highly portable.

Furthermore, according to the second invention, since the displacement measurement detector according to the first invention is used, not only can the above-mentioned numerous advantages be obtained, but also the displacement measurement detector according to the first invention can be used. It is possible to perform remote and centralized measurement at a point far away from the point.
It is safe because there is no need to climb to a high place, and there is no need for experienced personnel to perform installation and measurement.Therefore, installation and measurement costs can be reduced, and there is no need to interrupt the original excavation work. It is possible to provide a method for measuring the displacement of a tunnel interior that can quickly obtain sufficient information to understand the shape of the tunnel interior with good accuracy.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view for explaining an embodiment of the second invention, and the second part is a front view showing the configuration of an embodiment of the first invention, and FIGS. (B) is an explanatory diagram for explaining the principle of detecting the relative angle between adjacent sections, and FIGS. A diagram for explaining the measurement principle, FIG. 5 is a block diagram showing the configuration of an embodiment of the tunnel interior displacement measuring device according to the second invention, and FIG.
FIG. 2 is a front view showing a schematic configuration for explaining a conventional inner space displacement measuring method. 3...Tunnel inner wall, 9...Tunnel lining concrete, 10...
...Displacement detector. 11...Detector body, 12...Anchor jig, 13...Pulley for displacement measurement, 14...Displacement meter, 17.18... ...Angle meter, 15.16...1st. a second angle transmission arm; 19... wire, 29... weight, 30... scanner. 3I... Arithmetic unit, 32... Initial data setter, 33... Buffer, 34... X-Y printer.

Claims (2)

[Claims] (1) A detector body that is fixed to the measurement point on the inner wall of the tunnel by an anchor means, a pulley that is rotatably supported on the detector body, and a predetermined tension is applied to both ends of the detector body that is hung on the pulley. a displacement measuring converter provided on the detector body to detect the amount of rotation of the pulley with respect to the detector body and output an electric signal corresponding to the amount of rotation; first and second relative angle measuring transducers each detecting an angle in the drawing direction of each end of the wire with respect to the detector body and outputting an electrical signal corresponding to the angle; A detector for measuring displacement inside a tunnel, characterized in that it is configured to obtain an electric signal corresponding to the displacement and relative angle between adjacent measurement points or reference points necessary for understanding the cross-sectional form of the tunnel. . (2) Detection of a rotatable pulley, a displacement measurement converter that detects the amount of rotation of the pulley and outputs an electrical signal, and each end of the wire that is wrapped around the pulley in the main body of the detector that has an anchor means. Displacement measuring detectors each having a first and a second relative angle measuring transducer for detecting the pull-out direction angle with respect to the container body are installed at a plurality of measurement points on the inner wall of the tunnel with the anchor means. and tension applying means for fixing one end of one of the wires to a reference point on the inner wall of the tunnel, passing the wire around each pulley of the plurality of displacement measurement detectors in sequence, and applying a constant tension to the other end. and corresponds to the section displacement and relative angle of the relevant measured point with respect to the adjacent measured point or the reference point, which are output from the displacement measuring converter and the first and second relative angle measuring converters, respectively. A method for measuring displacement inside a tunnel, characterized in that the positional coordinates of each displacement measuring detector from the reference point are determined by a predetermined calculation based on an electric signal.