JP7174664B2 - Tunnel inner surface displacement measuring device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a device for measuring the displacement of the inner peripheral surface of a tunnel.

When constructing a tunnel, a shoring is constructed to support the inner wall of the natural ground. Since the shoring is under the heavy pressure of the ground, the shoring may be deformed and the inner surface of the tunnel may be displaced. When the displacement of the inner peripheral surface of the tunnel is large, it is necessary to reinforce the tunnel by driving rock bolts and sewing back the shoring. Desired.

As a method for measuring the displacement of the inner surface of the tunnel, a reference point is determined in advance and multiple targets such as anchors are installed on the inner surface of the tunnel. Methods are known for measuring and calculating the displacement of a target relative to a reference point. In this method, it is necessary to install targets on the inner peripheral surface of the tunnel, and the number of targets is limited (usually 3 to 5 in the tunnel circumferential direction at intervals of 20 m in the tunnel axial direction). Therefore, the displacement measurement points are limited, and the displacement of the inner peripheral surface of the tunnel cannot be measured accurately.

As another method for measuring the displacement of the inner peripheral surface of the tunnel, Patent Document 1 discloses that a three-dimensional laser scanner is used to detect minute unevenness on the inner peripheral surface of the tunnel, and the detected unevenness is used as a target to measure the inside of the tunnel. A method for measuring displacement of a circumferential surface is disclosed. Since the inner peripheral surface of the tunnel has a large number of irregularities, it is possible to accurately measure the displacement of the inner peripheral surface of the tunnel by calculating the displacement of the large number of irregularities. In addition, since it is possible to omit the operation of setting targets such as anchors, it is possible to efficiently measure the displacement of the inner circumferential surface of the tunnel.

In the displacement measuring method disclosed in Patent Literature 1, first, the laser beam of a three-dimensional laser scanner scans the inner circumferential surface of the tunnel to obtain three-dimensional coordinate values at the position irradiated with the laser beam. Using the acquired three-dimensional coordinate values, unevenness is detected and the unevenness pattern is extracted. The unevenness pattern is the height difference between an arbitrary position on the unevenness and its surroundings, and is calculated using three-dimensional coordinate values. Next, the inner peripheral surface of the tunnel is scanned with laser light again to detect unevenness having an uneven pattern similar to the uneven pattern extracted by the previous scanning with laser light, and to acquire the three-dimensional coordinate values thereof. The unevenness detected by the subsequent laser beam scanning is regarded as the movement destination of the unevenness detected by the previous laser beam scanning, and the difference between the three-dimensional coordinate values is calculated to calculate the unevenness displacement.

JP 2013-238549 A

In the displacement measurement method disclosed in Patent Document 1, since the uneven pattern is three-dimensional information that is the height difference between an arbitrary position on the uneven surface and its surroundings, it is possible to determine whether the uneven patterns are similar to each other. requires the processing of three-dimensional information. Therefore, it is difficult to compare the inner peripheral surfaces of the tunnel before and after the displacement, and the displacement of the inner peripheral surface of the tunnel cannot be easily measured. As a result, it may take a long time to measure the displacement of the inner peripheral surface of the tunnel, which may delay the reinforcement work of the tunnel, such as driving of rock bolts and retreading of shoring.

An object of the present invention is to easily measure the displacement of the inner peripheral surface of a tunnel.

The present invention is a tunnel inner circumferential surface displacement measuring device for measuring displacement of a tunnel inner circumferential surface, comprising: an obtaining unit for obtaining coordinates of a plurality of locations on the tunnel inner circumferential surface at first and second times; a generation unit that generates an uneven pattern on a predetermined cross section that intersects with the tunnel axis direction using the coordinates acquired by the generation unit; and a predetermined point at the first time and a predetermined point at the second time when the degree of unevenness at the first time calculated by the degree of unevenness calculating unit is similar to the degree of unevenness at the second time. and a difference calculation unit for calculating the difference between coordinates of predetermined points at first and second times corresponding to each other, and the degree of unevenness is determined in the tunnel circumferential direction so as to include the predetermined points. A first unevenness degree calculated using the coordinates of points on the uneven pattern within the first range set along the tunnel circumferential direction so as to include a predetermined point Set wider than the first range a second degree of unevenness calculated using the coordinates of points on the uneven pattern within the second range, and a third degree of unevenness calculated using the first degree of unevenness and the second degree of unevenness Including .

ADVANTAGE OF THE INVENTION According to this invention, the displacement of a tunnel inner peripheral surface can be measured easily.

1 is a schematic diagram of a tunnel inner circumferential surface displacement measuring device according to an embodiment of the present invention; FIG. 2 is a block diagram of the tunnel inner circumferential surface displacement measuring device shown in FIG. 1. FIG. 4 is a block diagram of a generator; FIG. FIG. 10 is a diagram showing an example of a concavo-convex pattern generated by a generation unit; It is a figure for demonstrating the procedure which calculates|requires curvature. FIG. 4 is an enlarged view schematically showing a concavo-convex pattern generated by a generator; FIG. 10 is a flow chart for explaining processing (steps S701 to S711) performed by an unevenness degree calculator; FIG. FIG. 10 is a flow chart for explaining processing (steps S801 to S806) performed by an unevenness degree calculation unit; FIG. It is a figure for demonstrating the 1st average curvature and the 2nd average curvature in the predetermined point on an uneven|corrugated pattern. 10 is a flow chart for explaining processing (steps S1001 to S1007) performed by a determination unit; 11 is a flow chart for explaining processing (steps S1101 to S1104) performed by a determination unit;

A tunnel inner circumferential surface displacement measuring device 100 and a tunnel inner circumferential surface displacement measuring method according to an embodiment of the present invention will be described below with reference to the drawings.

When constructing the tunnel T, a shoring M is constructed to support the inner wall of the natural ground. Since the shoring M is subjected to the heavy pressure of the ground, the shoring M may be deformed and the inner peripheral surface S of the tunnel may be displaced. When the displacement of the inner peripheral surface S of the tunnel is large, it is necessary to reinforce the tunnel T by driving rock bolts and sewing back the shoring M. Measurement is required.

In order to measure the displacement of the inner peripheral surface S of the tunnel over time, it is effective to measure the displacement of a characteristic portion of the inner peripheral surface S of the tunnel. The coordinates of the characteristic portion are obtained at a first time and at a second time after a predetermined time (for example, 6 hours) has elapsed from the first time, and the difference between the coordinates is obtained to obtain the displacement of the characteristic portion. It is possible to measure the displacement of the inner peripheral surface S of the tunnel over time.

In the tunnel inner peripheral surface displacement measuring device 100 and the tunnel inner peripheral surface displacement measuring method, unevenness formed on the tunnel inner peripheral surface S is used as a characteristic portion of the tunnel inner peripheral surface S. It is known that the inner peripheral surface S of the tunnel has a plurality of unevenness, and the degree of unevenness of each unevenness hardly changes even if the shape of the inner peripheral surface S of the tunnel changes as a whole. Therefore, by comparing the degrees of unevenness at the first and second times, it is possible to detect unevenness corresponding to each other between the tunnel inner peripheral surface S at the first time and the tunnel inner peripheral surface S at the second time. , displacements at a plurality of locations on the inner peripheral surface S of the tunnel can be accurately calculated. Therefore, the displacement of the inner peripheral surface S of the tunnel can be measured accurately. In addition, the work of setting targets such as anchors on the inner peripheral surface S of the tunnel can be omitted in addition to the unevenness, and the displacement of the inner peripheral surface S of the tunnel can be efficiently measured.

The unevenness of the tunnel inner peripheral surface S used as a characteristic part may be unevenness that is unintentionally formed when the tunnel T is constructed, or may be unevenness that is intentionally formed. .

The tunnel inner circumferential surface displacement measuring device 100 is composed of a computer 20 that analyzes coordinate information. The computer 20 includes a CPU (Central Processing Unit) that performs arithmetic processing, a ROM (Read-Only Memory) that stores control programs and the like executed by the CPU, and a RAM (random access memory) that stores the calculation results of the CPU and the like. and including.

The computer 20 is wired or wirelessly connected to a three-dimensional laser scanner 10 (hereinafter simply referred to as "scanner 10") installed in the tunnel T. As shown in FIG. The scanner 10 measures the position of the inner circumferential surface S of the tunnel and outputs information on the measured position.

The scanner 10 irradiates the tunnel inner peripheral surface S with laser light and detects the laser light reflected by the tunnel inner peripheral surface S, thereby measuring the position of the portion of the tunnel inner peripheral surface S irradiated with the laser light. do. The laser beam can be scanned on the inner peripheral surface S of the tunnel, and by irradiating multiple locations on the inner peripheral surface S of the tunnel with the laser beam, positions at multiple locations on the inner peripheral surface S of the tunnel can be measured.

The measurement by the scanner 10 is performed at the first time and the second time, and the installation position of the scanner 10 is substantially the same at the first time and the second time. That is, the scanner 10 measures a plurality of positions on the inner circumferential surface S of the tunnel at the first time and the second time with reference to the installation position of the scanner 10 .

Information on the measured position is output to the computer 20 as coordinates of a three-dimensional coordinate system. The three-dimensional coordinate system is, for example, an orthogonal coordinate system whose coordinate axes are three straight lines along the axial direction of the tunnel, the horizontal direction of the tunnel (perpendicular to the paper surface in FIG. 1), and the vertical direction.

The computer 20 uses the coordinates output from the scanner 10 to calculate the degree of unevenness of the unevenness at the first and second times, and compares the degrees of unevenness to determine the shape of the tunnel inner peripheral surface S at the first and second times. Concave and convex portions corresponding to each other are detected between them, and the displacement of the concave and convex portions is calculated.

Since the coordinates output from the scanner 10 are values of a three-dimensional coordinate system, when the degree of unevenness is calculated using the coordinates output from the scanner 10 as they are, the degree of unevenness becomes three-dimensional information, and the degree of unevenness can be compared. Collation of three-dimensional information is required. Therefore, it is difficult to detect unevenness corresponding to each other between the tunnel inner peripheral surface S at the first and second times, and the displacement of the tunnel inner peripheral surface S cannot be easily measured.

The tunnel inner circumferential surface displacement measuring apparatus 100 uses the coordinates output from the scanner 10 to generate a concavo-convex pattern on a predetermined cross section perpendicular to the tunnel axis direction, and measures the concavo-convex pattern at a predetermined point on the concavo-convex pattern. Calculate the degree. Therefore, the degree of unevenness is two-dimensional information, and the degrees of unevenness can be compared by collating the two-dimensional information. Therefore, the uneven patterns can be easily compared, and the unevenness corresponding to each other can be easily detected between the tunnel inner peripheral surfaces S at the first and second times. Thereby, the displacement of the inner peripheral surface S of the tunnel can be easily measured.

In addition, the tunnel inner peripheral surface S is mainly displaced in the lateral and vertical directions of the tunnel, and hardly displaced in the axial direction of the tunnel. That is, the unevenness on the predetermined cross section at the first time is on the same predetermined cross section at the second time. Therefore, even when comparing uneven patterns on a predetermined cross section perpendicular to the tunnel axial direction, the corresponding unevenness is determined between the tunnel inner peripheral surface S at the first time and the tunnel inner peripheral surface S at the second time. can be detected. Further, even if the difference between the corresponding unevennesses detected in this manner is used as the displacement of the inner peripheral surface S of the tunnel, the measurement accuracy does not decrease.

As shown in FIG. 2, the computer 20 includes an acquisition unit 30 that acquires the coordinates output from the three-dimensional laser scanner 10, and a generation unit 40 that generates uneven patterns at first and second times using the coordinates. , an unevenness degree calculator 50 that calculates the unevenness degree at a predetermined point on the uneven pattern at the first and second times, and a predetermined point on the uneven pattern at the first and second times based on the unevenness degree A determination unit 60 that determines whether or not there is correspondence, and a difference calculation unit 70 that calculates a difference in coordinates at a predetermined point on the uneven pattern at the first and second times. The acquisition unit 30, the generation unit 40, the unevenness degree calculation unit 50, the determination unit 60, and the difference calculation unit 70 are virtual units of the function of the computer 20 for measuring the displacement of the inner peripheral surface S of the tunnel. is.

Acquisition unit 30 acquires a first group of coordinates, which are coordinates at a plurality of locations on tunnel inner peripheral surface S at a first time, and coordinates at a plurality of locations on tunnel inner peripheral surface S at a second time. Obtain a second set of coordinates.

The generation unit 40 generates a first uneven pattern, which is the uneven pattern on the predetermined cross section at the first time, using the first coordinate group, and generates a first uneven pattern, which is the uneven pattern on the same predetermined cross section at the second time. A two-relief pattern is generated using the second set of coordinates. Here, the predetermined cross section is a cross section along line CC shown in FIG. 1 (hereinafter referred to as "CC cross section").

Although the scanner 10 can measure positions at many points on the inner peripheral surface S of the tunnel, the number of measurement points on the CC cross section is limited. Therefore, if the unevenness pattern is generated using only the coordinates on the CC cross section, the accuracy of the unevenness pattern may decrease, and the accuracy of the unevenness degree calculated by the unevenness degree calculation unit 50 may decrease. . Therefore, in the present embodiment, the generation unit 40 generates the concave-convex pattern using coordinates within a predetermined range R set along the tunnel axis direction so as to include the CC cross section.

As shown in FIG. 3, the generation unit 40 includes an extraction unit 41 that extracts coordinates within a predetermined range R from the plurality of coordinates acquired by the acquisition unit 30, and a projection unit that projects the extracted coordinates onto the CC cross section. and a specifying unit 43 that specifies a figure formed from the projected coordinates as a concavo-convex pattern.

The extraction unit 41 extracts coordinates within a predetermined range R from the plurality of coordinates acquired by the acquisition unit 30 based on the values of the coordinate axes along the tunnel axis direction. Specifically, the coordinates whose values of the coordinate axis along the tunnel axis direction are values within the predetermined range R are extracted, and the coordinates whose values of the coordinate axis along the tunnel axis direction are values outside the predetermined range R are excluded.

The predetermined range R is preset. The predetermined range R may be changeable by the operator. The predetermined range R is preferably set according to the size of unevenness that can be a characteristic portion, and is set, for example, within a range of 5 mm on both sides in the tunnel axial direction from the cross section CC.

The projection unit 42 projects the coordinates extracted by the extraction unit 41 onto the CC cross section by converting the values of the coordinate axes along the tunnel axis direction in the extracted coordinates into values corresponding to the CC cross section. . The coordinates after projection are the coordinates on the CC section. That is, the coordinates extracted by the extraction unit 41 are converted into coordinates of the two-dimensional coordinate system by projection onto the CC section.

The specifying unit 43 specifies a figure formed by sequentially connecting the coordinates projected on the CC cross section in the circumferential direction of the tunnel as the concave-convex pattern. Since the coordinates after projection are the coordinates on the CC cross section, the figure specified as the uneven pattern is a plane figure on the CC cross section. Therefore, the uneven pattern serves as two-dimensional information.

FIG. 4 shows an example of the uneven pattern specified by the specifying unit 43 of the generating unit 40. As shown in FIG. The first uneven pattern is the uneven pattern at the first time, and the second uneven pattern is the uneven pattern at the second time. In FIG. 4, for convenience of explanation, the difference in size between the first uneven pattern and the second uneven pattern is exaggerated.

As shown in FIG. 4, the curvatures of corresponding unevenness between the first and second uneven patterns are similar to each other. Therefore, in the present embodiment, the curvature at a predetermined point on the first and second uneven patterns is defined as the degree of unevenness, and the curvature at a predetermined point on the first and second uneven patterns is compared to obtain the first and second unevenness patterns. 2 It is determined whether predetermined points on the concave-convex pattern correspond to each other. The curvature at each coordinate is calculated by the unevenness degree calculator 50 (see FIG. 2). determined by

When calculating the curvature, the equation of a circle may be used, but in this case, it is necessary to assume a circle passing through three points and solve the equation of the three circles, which may complicate the process. There is Therefore, here, the curvature is calculated using the length of the line segment connecting adjacent points in the tunnel circumferential direction and the difference in inclination between the adjacent points. The procedure for obtaining the curvature will be described in more detail with reference to FIG.

FIG. 5 is a diagram for explaining the procedure for obtaining the curvature at point M on circle C. As shown in FIG. Point O is the center of circle C. The slope of the tangent line TM at the point M (the angle between the tangent line TM and the horizontal axis) is α [rad], and the slope of the tangent line TN at the point N on the circle C (the angle between the tangent line TN and the horizontal axis) is Let β [rad].

In FIG. 5, the angle γ [rad] of the central angle MON is
γ = β - α
is represented. That is, the angle γ of the central angle MON is the difference between the slope of the tangent line TN and the slope of the tangent line TM.

Using the radius Rc of the circle C and the angle (β-α) of the central angle MON, the length LA of the arc MN is
LA=Rc×(β−α)
is represented. That is, the radius Rc is
Rc=LA/(β-α)
is represented.

If the point N is very close to the point M, the length LA of the arc MN can be approximated to the length LS of the line segment MN, so the radius Rc is
Rc≈LS/(β-α)
becomes. Since the curvature K of the arc MN is the reciprocal of the radius Rc,
K≈(β-α)/LS (1)
becomes.

In the present embodiment, since the generation unit 40 generates the concave-convex pattern using the coordinates projected onto the CC cross section, the concave-convex pattern includes points whose coordinates are known (hereinafter referred to as "known coordinate points"). contains many. In other words, it can be considered that points with known coordinates adjacent to each other in the tunnel circumferential direction in the concave-convex pattern are positioned extremely close to each other. Therefore, using equation (1), the curvature at a point with known coordinates on the uneven pattern can be calculated.

The processing by the unevenness degree calculator 50, that is, the processing of calculating the curvature at a point with known coordinates on the uneven pattern will be described with reference to FIGS. 6 and 7. FIG.

FIG. 6 is an enlarged view schematically showing the uneven pattern, showing five points P with known coordinates. For convenience of explanation, the five known coordinate points P are referred to as known coordinate points Pn-2, Pn-1, Pn, Pn+1 and Pn+2 in order in the counterclockwise direction in FIG.

In step S701, one coordinate known point Pn is selected on the concave-convex pattern generated by the generation unit 40. FIG.

In step S702, the distance Ln between the coordinates known points Pn and Pn+1 is calculated. The calculated distance Ln corresponds to the length LS of the line segment MN in FIG.

In step S703, the slope Sn [rad] of the tangent line at the known coordinate point Pn is calculated. Specifically, the slope of a straight line passing through known coordinate points Pn and Pn+1 is calculated, the slope passing through known coordinate points Pn and Pn−1 is calculated, the average of these slopes is calculated, and the average of the calculated slopes is calculated. be the slope Sn of the tangent line at the coordinate known point Pn. The slope Sn corresponds to the slope α of the tangent line TM in FIG.

In step S704, the slope Sn+1 [rad] of the tangent line at the coordinate known point Pn+1 is calculated. Specifically, the slope of the straight line passing through the known coordinate points Pn+1 and Pn+2 is calculated, the slope passing through the known coordinate points Pn+1 and Pn is calculated, the average of these slopes is calculated, and the average of the calculated slopes is Let Sn+1 be the slope of the tangent line at the coordinate known point Pn+1. The slope Sn+1 corresponds to the slope β of the tangent line TN in FIG.

In step S705, using the distance Ln and the slopes Sn and Sn+1, the curvature at the known coordinate point Pn is calculated assuming that the known coordinate point Pn+1 is located very close to the known coordinate point Pn. Specifically, the curvature is calculated by substituting the distance Ln and the slopes Sn and Sn+1 calculated in steps S702, S703 and S704 into the length LS and the slopes α and β of the equation (1).

The curvature calculated in step S705 is strongly influenced by the known coordinate point Pn+1 because the slope Sn+1 of the tangent line at the known coordinate point Pn+1 is used. Therefore, the unevenness degree calculation unit 50 calculates the curvature at the known coordinate point Pn when it is assumed that the known coordinate point Pn-1 is located very close to the known coordinate point Pn, and calculates the average of the two curvatures at the known coordinate point. Let it be the curvature at Pn.

Specifically, in step S706, the distance Ln-1 between the known coordinate points Pn-1 and Pn is calculated. In step S707, the slope Sn-1 [rad] of the tangent line at the coordinate known point Pn-1 is calculated. In step S708, the distance Ln-1 and the slopes Sn and Sn-1 are substituted into equation (1), and the known coordinate point Pn obtained when it is assumed that the known coordinate point Pn-1 is located very close to the known coordinate point Pn is calculated. Calculate the curvature at

In step S709, the average of the curvature calculated in step S705 and the curvature calculated in step S708 is calculated, and the calculated average is used as the curvature at the known coordinate point Pn.

By the above, the calculation of the curvature at the coordinate known point Pn is completed.

In steps S702 to S709, known coordinate points Pn-2, Pn-1, Pn+1 and Pn+2 are used in addition to the known coordinate point Pn to calculate the curvature at the known coordinate point Pn. That is, since it is not possible to calculate the radius of curvature at two known coordinate points at each end in the circumferential direction of the tunnel, the known coordinate points at which the radius of curvature can be calculated (hereinafter referred to as "calculation target points") are are the known coordinate points on the concave-convex pattern excluding two known coordinate points at each end (four in total).

In step S710, it is determined whether or not steps S702 to S709 have been executed for all calculation target points. If it is determined that steps S702 to S709 have not been executed for all calculation target points, the process proceeds to step S711. In step S711, another point with known coordinates is selected on the uneven pattern, and the process returns to step S702. If it is determined in step S710 that steps S702 to S709 have been executed for all calculation target points, the process proceeds to step S801.

Since the curvature calculated in steps S702 to S709 is calculated from five coordinates of known points, it can capture only local changes in the concave-convex pattern, and may be affected by noise data. Although it may be determined whether or not the known coordinate points selected on the first and second concave-convex patterns correspond to each other based on such a curvature, there is a possibility that the precision may be lowered.

Therefore, as shown in FIG. 9, the unevenness degree calculator 50 defines a first range R1 along the circumferential direction of the tunnel so that the selected known coordinate point P is the center and six or more known coordinate points are included. Then, the average curvature of points with known coordinates within the first range R1 is calculated. That is, the first average curvature (first unevenness degree) is calculated using the coordinates of the points on the uneven pattern within the first range R1. Compared with the curvature calculated from the five coordinate-known points, the first average curvature can largely grasp the change in the concave-convex pattern and can reduce the influence of noise data. Therefore, by comparing the first average curvatures of the first and second uneven patterns, it is possible to accurately determine whether or not the known coordinate points P selected on the first and second uneven patterns correspond to each other. can be done.

Further, in the unevenness degree calculation unit 50, a second range R2 larger than the first range R1 is set along the tunnel circumferential direction so that the selected coordinate known point P is the center, and Calculate the average curvature at a point with known coordinates. That is, the second average curvature (second degree of unevenness) is calculated using the coordinates of points on the uneven pattern within the second range R2. Compared with the first average curvature, the second average curvature can catch the change of the concave-convex pattern to a greater extent. Therefore, since the first average curvature and the second average curvature that capture changes in the uneven pattern in different ranges can be compared, the coordinate known points that correspond to each other between the first and second uneven patterns can be detected with high accuracy. be able to.

Further, the unevenness degree calculator 50 calculates the ratio of the first average curvature to the second average curvature at the selected coordinate known point P (hereinafter referred to as "average curvature ratio") as the third unevenness degree. The larger the average curvature ratio, the larger the first average curvature and the smaller the second average curvature. There will be By using such a known coordinate point as a singular point on the concave-convex pattern and excluding other known coordinate points from comparison targets, the mutually corresponding known coordinate points can be efficiently determined between the first and second concave-convex patterns. can be detected.

Additional processing by the unevenness degree calculator 50, that is, processing for calculating the first average curvature, the second average curvature, and the average curvature ratio at a point with known coordinates on the uneven pattern will be described with reference to FIGS. 8 and 9. .

In step S801, one coordinate known point P is selected on the concave-convex pattern generated by the generation unit 40. FIG.

In step S802, a first range R1 is set along the circumferential direction of the tunnel so that the selected known coordinate point P is the center, and the average curvature of the known coordinate points within the first range R1 is calculated. The calculated value is the first mean curvature at the selected point P with known coordinates.

In step S803, a second range R2 is set along the circumferential direction of the tunnel so that the selected point P with known coordinates is the center, and the average curvature of the points with known coordinates within the second range R2 is calculated. The calculated value is the second mean curvature at the selected point P with known coordinates.

The width of the first range R1 and the width of the second range R2 are preset. The width of the first range R1 and the width of the second range R2 may be changeable by the operator. The width of the first range R1 is, for example, about 1/10000 to 1/50 of the length of the tunnel inner peripheral surface S in the tunnel circumferential direction. The width of the second range R2 is, for example, about 1/100 to 1/3 of the length of the tunnel inner peripheral surface S in the tunnel circumferential direction.

In step S804, the average curvature ratio at the selected coordinate known point P is calculated by dividing the first average curvature by the second average curvature.

In step S805, it is determined whether or not steps S802 to S804 have been executed for all calculation target points. If it is determined that steps S802 to S804 have not been executed for all points to be calculated, the process proceeds to step S806. In step S806, another point with known coordinates is selected on the uneven pattern, and the process returns to step S802. If it is determined in step S805 that steps S802 to S804 have been executed for all points to be calculated, the processing by the unevenness degree calculator 50 ends.

Steps S701 to S711 and steps S801 to S806 are respectively executed for the first uneven pattern and the second uneven pattern, and the first average curvature, the second average curvature and the average curvature at each coordinate known point of the first uneven pattern ratio, the first average curvature, the second average curvature, and the average curvature ratio at each coordinate known point of the second uneven pattern are calculated.

The calculated first average curvature, second average curvature, and average curvature ratio are used in the processing by the determination unit 60 . 10 and 11, the processing by the determination unit 60, that is, the processing of determining whether or not known coordinate points on the first and second uneven patterns correspond to each other will be described.

As shown in FIG. 10, in step S1001, one coordinate known point is selected on the first uneven pattern.

In step S1002, it is determined whether or not the average curvature ratio at the known coordinate points selected on the first concave-convex pattern is equal to or greater than the first threshold. If the average curvature ratio at the selected point with known coordinates is less than the first threshold, it is determined that the selected point with known coordinates is not a singular point on the first concave-convex pattern, and the process proceeds to step S1103. The processing in step S1103 will be described later. In step S1002, if the average curvature ratio at the known coordinate point selected on the first concave-convex pattern is equal to or greater than the first threshold value, the selected known coordinate point is determined to be a singular point on the first concave-convex pattern. It determines, and it progresses to step S1003.

In step S1003, one coordinate known point is selected on the second uneven pattern.

In step S1004, it is determined whether or not the average curvature ratio at the known coordinate point selected on the second uneven pattern is equal to or greater than the second threshold. If the average curvature ratio at the selected point with known coordinates is less than the second threshold, it is determined that the selected point with known coordinates is not a singular point on the second concave-convex pattern, and the process proceeds to step S1101. The processing in step S1101 will be described later. In step S1004, if the average curvature ratio at the known coordinate point selected on the second uneven pattern is equal to or greater than the second threshold, the selected known coordinate point is determined to be a singular point on the second uneven pattern. It determines, and it progresses to step S1005.

The first threshold used in step S1002 and the second threshold used in step S1004 are preset. The first threshold and the second threshold may be changeable by the operator. The first threshold and the second threshold may be set to the same value or may be set to different values.

In step S1005, it is determined whether or not the second average curvature at the known coordinate point selected on the first uneven pattern is similar to the second average curvature at the known coordinate point selected on the second uneven pattern. do. Specifically, when the difference between the second average curvatures is equal to or less than the third threshold, it is determined that they are similar, and when the difference between the second average curvatures is greater than the third threshold, it is determined that they are not similar.

If it is determined in step S1005 that the second average curvatures are not similar, the process proceeds to step S1103. If it is determined in step S1005 that the second average curvatures are similar to each other, the process proceeds to step S1006.

In step S1006, it is determined whether or not the first average curvature at the point with known coordinates selected on the first uneven pattern is similar to the first average curvature at the point with known coordinates selected on the second uneven pattern. do. Specifically, when the difference between the first average curvatures is equal to or less than a fourth threshold, it is determined that they are similar, and when the difference between the first average curvatures is greater than the fourth threshold, it is determined that they are not similar.

The third threshold used in step S1005 and the fourth threshold used in step S1006 are set in advance. The third threshold and the fourth threshold may be changeable by the operator. The third threshold and the fourth threshold may be set to the same value or may be set to different values.

If it is determined in step S1006 that the first average curvatures are not similar, the process proceeds to step S1101. If it is determined in step S1006 that the first average curvatures are similar to each other, the process proceeds to step S1007.

In step S1007, if the known coordinate point selected on the first concave-convex pattern corresponds to the known coordinate point selected on the second concave-convex pattern, it is stored in a storage unit (not shown), and the process proceeds to step S1103.

In step S1101, it is determined whether or not all calculation target points on the second uneven pattern have been selected. If it is determined in step S1101 that all calculation target points have not been selected, the process advances to step S1102. In step S1102, another point with known coordinates is selected on the second uneven pattern, and the process returns to step S1003. If it is determined in step S1101 that all calculation target points have been selected, the process advances to step S1103.

In step S1103, it is determined whether or not all calculation target points on the first uneven pattern have been selected. If it is determined in step S1103 that all calculation target points have not been selected, the process advances to step S1104. In step S1104, another point with known coordinates is selected on the first uneven pattern, and the process returns to step S1002. If it is determined in step S1103 that all calculation target points have been selected, the processing by the determination unit 60 ends.

As described above, detection of mutually corresponding known coordinate points between the first and second uneven patterns is completed.

The difference calculator 70 (see FIG. 2) calculates the difference between corresponding known coordinate points on the first and second uneven patterns. The calculated difference corresponds to the displacement of the inner peripheral surface S of the tunnel. Measurement of displacement is completed by the above. The measured displacement is displayed on the monitor 80 (see FIGS. 1 and 2).

According to the present embodiment described above, the following effects can be obtained.

In the tunnel inner circumferential surface displacement measuring device 100 and the tunnel inner circumferential surface displacement measuring method, first and second uneven patterns are generated on the CC cross section crossing the tunnel axial direction, and the first and second uneven patterns are generated. Calculate the degree of unevenness at a point with known coordinates. Therefore, the degree of unevenness is two-dimensional information, and the degrees of unevenness can be compared by collating the two-dimensional information. Therefore, the first and second patterns of unevenness can be easily compared, and unevenness corresponding to each other between the tunnel inner peripheral surface S at the first and second times can be easily detected. Thereby, the displacement of the inner peripheral surface S of the tunnel can be easily measured.

In the tunnel inner circumferential surface displacement measuring device 100 and the tunnel inner circumferential surface displacement measuring method, coordinates within a predetermined range R set along the tunnel axial direction so as to include the CC cross section are extracted from the acquired coordinates. Then, the extracted coordinates are projected onto the CC cross section, and the uneven pattern is specified using the projected coordinates. Therefore, it is possible to increase the number of coordinates used for generating the concave-convex pattern, and to generate the concave-convex pattern with high accuracy. As a result, it is possible to accurately detect unevenness corresponding to each other between the tunnel inner peripheral surface S at the first and second times, and to measure the displacement of the tunnel inner peripheral surface S with high accuracy.

In the tunnel inner circumferential surface displacement measuring device 100 and the tunnel inner circumferential surface displacement measuring method, known coordinate points within a first range R1 set along the circumferential direction of the tunnel so that the selected known coordinate point P is the center In addition to calculating the first average curvature at, known coordinate points in a second range R2 set wider than the first range R1 along the tunnel circumferential direction so that the selected known coordinate point P is the center , and divide the first average curvature by the second average curvature to calculate the average curvature ratio. The larger the average curvature ratio, the larger the first average curvature and the smaller the second average curvature, so that the selected coordinate known point P is a characteristic part point that is greatly recessed or greatly protruded with respect to its surroundings. can be determined based on the average curvature ratio. The tunnel inner peripheral surface S It is possible to efficiently detect unevenness corresponding to each other between and efficiently measure the displacement of the inner peripheral surface S of the tunnel.

In the tunnel inner circumferential surface displacement measuring device 100 and the tunnel inner circumferential surface displacement measuring method, when the degree of unevenness of a point with known coordinates is equal to or greater than the first threshold value or the second threshold value, the point with known coordinates is determined to be a singular point. It is determined whether or not the unevenness degree of the singular point at the first time is similar to the unevenness degree of the singular point at the second time. Since the unevenness corresponding to each other between the tunnel inner peripheral surface S at the first and second times can be detected with high accuracy by comparing the singular points, the displacement of the tunnel inner peripheral surface S can be measured with high accuracy. .

In the tunnel inner circumferential surface displacement measuring device 100 and the tunnel inner circumferential surface displacement measuring method, it is determined that the second average curvature of the singular points at the first time is similar to the second average curvature of the singular points at the second time, and When it is determined that the first average curvature of the singularity at time 1 and the second average curvature of the singularity at the second time are similar, it is determined that the singularity at the first time corresponds to the singularity at the second time. . Since it is possible to compare the uneven patterns by catching changes in the uneven patterns in different ranges, it is possible to accurately detect the unevenness corresponding to each other between the tunnel inner peripheral surfaces S at the first and second times. Therefore, the displacement of the inner peripheral surface S of the tunnel can be measured with high accuracy.

Although the embodiments of the present invention have been described above, the above embodiments merely show a part of application examples of the present invention, and the technical scope of the present invention is not limited to the specific configurations of the above embodiments. do not have.

In the above embodiment, the three-dimensional laser scanner 10 is used to measure positions at multiple locations on the tunnel inner peripheral surface S. Instead of the three-dimensional laser scanner 10, a stereo camera, profiler and LiDAR (Light Detection and Ranging) are used. A range sensor such as a range sensor may be used. In addition, it is also possible to irradiate the inner peripheral surface S of the tunnel with moire fringes and measure the positions at a plurality of locations on the inner peripheral surface S of the tunnel, or to measure the positions at a plurality of locations on the inner peripheral surface S of the tunnel using a UAV (Unmanned Aerial Vehicle). Position may be measured.

In the above embodiment, coordinates within a predetermined range R set along the tunnel axis direction so as to include the CC cross section are extracted from the obtained coordinates, and the extracted coordinates are projected onto the CC cross section. However, instead of this, the uneven pattern may be generated by interpolating the coordinates of the inner peripheral surface S of the tunnel on the CC cross section. Even in this case, the accuracy of the uneven pattern can be improved, and the unevenness corresponding to each other between the tunnel inner peripheral surface S at the first and second times can be detected with high accuracy. Therefore, the displacement of the inner peripheral surface S of the tunnel can be measured with high accuracy.

In the above embodiment, the degree of unevenness is the curvature at the known coordinate point P selected on the uneven pattern. The degree of skewness may be used as the degree of unevenness.

The inclination at the coordinate known point P is calculated in step S703. As with the first average curvature, the first average inclination (first unevenness degree) sets the first range R1 along the tunnel circumferential direction so that the selected coordinate known point P is the center, and the first range It is obtained by calculating the average of the slopes at points with known coordinates within R1. As with the second average curvature, the second average inclination (second unevenness degree) sets a second range R2 along the tunnel circumferential direction so that the selected coordinate known point P is the center, and the second range It is obtained by calculating the average of the slopes at points with known coordinates within R2. The average slope ratio (third unevenness degree) is obtained by calculating the ratio of the first average slope to the second average slope at the selected point P with known coordinates, in the same manner as the average curvature ratio.

と定義されるため、距離成分ｒの平均μ及び標準偏差σを算出して式（２）及び式（３）に代入することにより、及び歪度を算出することができる。第１平均傾き（第１凹凸度合）は、第１平均曲率と同様に、選択された座標既知点Ｐが中心となるようにトンネル周方向に沿って第１範囲Ｒ１を設定し、第１範囲Ｒ１内にある座標既知点における傾きの平均を算出することにより得られる。第２平均傾き（第２凹凸度合）は、第２平均曲率と同様に、選択された座標既知点Ｐが中心となるようにトンネル周方向に沿って第２範囲Ｒ２を設定し、第２範囲Ｒ２内にある座標既知点における傾きの平均を算出することにより得られる。平均傾き比（第３凹凸度合）は、平均曲率比と同様に、選択された座標既知点Ｐでの第２平均傾きに対する第１平均傾きの比を算出することにより得られる。 The kurtosis and skewness can be calculated by expressing the coordinates of points on the uneven pattern in polar coordinates. Specifically, if the coordinates of the points on the concave-convex pattern are polar coordinates with the center of the tunnel T on the CC cross section as the origin, the horizontal axis for the selected point P with known coordinates is the angle component θ of the polar coordinates. , the vertical axis can be the distance component r=E(θ) in polar coordinates. Note that E(θ) is an expected value function. Kurtosis K and skewness S are obtained by using the mean μ and standard deviation σ of the distance component r,

Therefore, the skewness can be calculated by calculating the average μ and standard deviation σ of the distance component r and substituting them into the equations (2) and (3). As with the first average curvature, the first average inclination (first unevenness degree) sets the first range R1 along the tunnel circumferential direction so that the selected coordinate known point P is the center, and the first range It is obtained by calculating the average of the slopes at points with known coordinates within R1. As with the second average curvature, the second average inclination (second unevenness degree) sets a second range R2 along the tunnel circumferential direction so that the selected coordinate known point P is the center, and the second range It is obtained by calculating the average of the slopes at points with known coordinates within R2. The average slope ratio (third unevenness degree) is obtained by calculating the ratio of the first average slope to the second average slope at the selected point P with known coordinates, in the same manner as the average curvature ratio.

In the above embodiment, in step S802, the first range R1 is set so that the selected point P with known coordinates is the center. should be set to Similarly, in step S803, the second range R2 is set so that the selected point P with known coordinates is the center, but the second range R2 is set so as to include the selected point P with known coordinates. I wish I could.

In the above embodiment, an unevenness pattern is generated on one C--C cross section and the degree of unevenness is calculated. good too. In this case, the displacement of the inner peripheral surface S of the tunnel can be measured at a plurality of points in the axial direction of the tunnel.

DESCRIPTION OF SYMBOLS 100... Tunnel inner peripheral surface displacement measuring apparatus 30... Acquisition part 40... Generation part 50... Unevenness degree calculation part 60... Judgment part 70... Difference calculation part T... Tunnel S ... Tunnel inner peripheral surface R1 ... First range R2 ... Second range

Claims (4)

A tunnel inner peripheral surface displacement measuring device for measuring displacement of a tunnel inner peripheral surface,
an acquisition unit that acquires coordinates of a plurality of locations on the inner circumferential surface of the tunnel at first and second times;
a generating unit that generates an uneven pattern on a predetermined cross section that intersects with the tunnel axis direction using the coordinates acquired by the acquiring unit;
an unevenness degree calculation unit that calculates an unevenness degree at a predetermined point on the uneven pattern at the first and second times generated by the generation unit;
When the degree of unevenness at the first time and the degree of unevenness at the second time calculated by the degree of unevenness calculation unit are similar, the predetermined point at the first time and the predetermined point at the second time. a determination unit that determines that corresponds to
a difference calculation unit that calculates the difference between the coordinates of the predetermined point at the first and second times corresponding to each other ;
The degree of unevenness is a first degree of unevenness calculated using coordinates of points on the uneven pattern within a first range set along the tunnel circumferential direction so as to include the predetermined point, and the predetermined point. A second unevenness degree calculated using coordinates of points on the uneven pattern within a second range set wider than the first range along the tunnel circumferential direction so as to include the first A third degree of unevenness calculated using the degree of unevenness and the second degree of unevenness,
Tunnel inner circumferential surface displacement measuring device. The generating unit extracts coordinates within a predetermined range set along the tunnel axis direction so as to include the predetermined cross section from the coordinates obtained by the obtaining unit, and converts the extracted coordinates to the 2. The tunnel inner circumferential surface displacement measuring device according to claim 1, wherein the uneven pattern is specified by projecting it onto a predetermined cross section and using the coordinates after projection. The determination unit determines that the predetermined point is a singular point when the third degree of unevenness of the predetermined point is equal to or greater than a predetermined value, and determines the first and second degrees of unevenness of the singular point at the first time. 3. The tunnel inner circumferential surface displacement measuring device according to claim 1, wherein it is determined whether or not the first and second unevenness degrees of the singular point at the second time are similar to each other. The determination unit determines that the second unevenness degree of the singular point at the first time and the second unevenness degree of the singular point at the second time are similar, and the singular point at the first time and the first unevenness degree of the singular point at the second time are similar, the singular point at the first time corresponds to the singular point at the second time to judge,
The tunnel inner circumferential surface displacement measuring device according to claim 3 .

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