Round tunnel section displacement and convergence deformation monitoring method

Abstract

The invention discloses a circular tunnel section displacement and convergence deformation monitoring method, which comprises the following steps that: four mark points are uniformly distributed on the inner wall of a tunnel lining to which a monitored section belongs, and the monitored section is vertical to the axis of a tunnel; the method comprises the following steps: determining an acquisition period, acquiring mark point data of the inner wall of a tunnel lining in a three-dimensional laser scanning manner every other acquisition period, and processing the acquired mark point data; calculating centroid coordinates of the monitored section in different periods according to the processed mark point data; calculating the displacement of the monitored section according to the centroid coordinates in different periods; according to the centroid coordinates in different periods, calculating the vertical and transverse spacing of the lining inner wall of the monitored section in different periods, and calculating the vertical and transverse convergence deformation of the monitored section according to the vertical and transverse spacing in different periods. According to the invention, data acquisition is convenient, efficient and high in precision, and convergence deformation monitoring and displacement monitoring can be carried out on any section of the tunnel at any period.

Description

Technical Field

[0001] The invention relates to the field of underground engineering monitoring, and in particular to a method for monitoring displacement and convergence deformation of a circular tunnel section. Background Art

[0002] During the construction and operation of tunnels, affected by changes in the external environment and sudden loads, different degrees of displacement will occur, which may cause structural damage, traffic interruption and even casualties. It is necessary to monitor tunnel displacement regularly. At present, tunnel displacement monitoring often uses instruments such as levels and total stations. With the development of surveying and mapping technology, 3D laser scanners have been increasingly used in the engineering field. Compared with traditional single-point measurement, they have the advantages of fast speed and high precision. The "Technical Specifications for Operation Monitoring of Urban Rail Transit Facilities-Part 3: Tunnels" clearly requires that the vertical displacement of the main structure of the tunnel should be measured and the horizontal displacement should be measured. It focuses on the position change of a single point on the tunnel section, but does not make requirements for the overall displacement of the tunnel. At the same time, the safety and stability of subway tunnels are related to the normal operation of the subway and the safety of passengers' lives. It is very necessary to conduct regular safety monitoring of tunnels. The "Technical Specifications for Operation Monitoring of Urban Rail Transit Facilities-Part 3: Tunnels" clearly requires the convergence deformation of tunnels. Traditional tunnel convergence deformation monitoring generally uses total stations, convergence meters and other means, which have low work efficiency and are difficult to monitor the convergence deformation of the entire tunnel in real time and efficiently. Summary of the invention

[0003] The present invention provides a circular tunnel section displacement and convergence deformation monitoring method to overcome the above technical problems.

[0004] A circular tunnel section displacement and convergence deformation monitoring method, comprising:

[0005] S1. Four marking points are evenly arranged on the inner wall of the tunnel lining to which the monitored section belongs. The monitored section is perpendicular to the tunnel axis.

[0006] S2. Determine a collection cycle, collect the marking point data of the inner wall of the tunnel lining by three-dimensional laser scanning every collection cycle, and process the collected marking point data;

[0007] S3, calculating the centroid coordinates of the monitored section at different periods according to the processed marking point data;

[0008] S4. Calculate the displacement of the monitored section according to the centroid coordinates at different periods;

[0009] S5. According to the centroid coordinates at different periods, calculate the vertical and horizontal spacing of the inner wall of the lining of the monitored section at different periods. According to the vertical and horizontal spacing at different periods, calculate the vertical and horizontal convergence deformation of the monitored section, and feed back the displacement, vertical convergence deformation and horizontal convergence deformation of the monitored section to the staff.

[0010] Preferably, the calculation of the centroid coordinates of the monitored section at different periods includes calculating the centroid coordinates of period t according to formulas (1) and (2):

[0011]

[0012] in, represents the abscissa of the cross-section centroid at period t, represents the ordinate of the centroid of the section at period t, A represents the area of ​​the section at period t, f(x,y) represents the density function of the region where the section is located at period t, χ represents the abscissa of the area unit dA at period t, y represents the ordinate of the area unit dA at period t, and Ω represents the area domain of the tunnel section at period t.

[0013] Preferably, S4 includes calculating the overall lateral displacement of the cross section according to formula (3), calculating the overall longitudinal displacement of the cross section according to formula (4), and calculating the overall displacement of the cross section according to formula (5).

[0014]

[0015]

[0016] Among them, X represents the overall lateral displacement of the section, Y represents the overall vertical displacement of the section, and Δ represents the overall displacement of the section. represents the abscissa of the centroid of the cross section after deformation, Represents the vertical coordinate of the centroid of the cross section after deformation.

[0017] Preferably, the calculating of the vertical and lateral convergence deformation of the monitored section according to the vertical and lateral spacings at different periods includes calculating the vertical convergence deformation of the tunnel according to formula (6), and calculating the lateral convergence deformation of the tunnel according to formula (7).

[0018] Δ v =D v ′-D v (6)

[0019] Δ h =D h ′-D h (7)

[0020] Among them, Δ v represents the vertical convergence deformation of the tunnel, Δ hrepresents the lateral convergence deformation of the tunnel, D v Indicates the vertical spacing of the sections before deformation, D h Indicates the transverse distance of the cross section before deformation, D v ′ represents the vertical spacing of the section after deformation, D h ′ represents the transverse spacing of the cross section after deformation.

[0021] Preferably, the marking point is a physical mark that is easy to identify and permanently fixed to the inner wall of the tunnel.

[0022] The present invention provides a method for monitoring the displacement and convergence deformation of a circular tunnel section. The method collects data of marking points on the inner wall of a tunnel lining by means of three-dimensional laser scanning, calculates the centroid coordinates of the same section at different times, and calculates the overall displacement of the tunnel section by using the change of the centroid coordinates. The present invention has high implementation efficiency and high accuracy, and can monitor the displacement of a target tunnel section at different times, thereby providing technical support for tunnel construction and operation and maintenance. The present invention measures the spacing of the inner wall of the lining in the vertical and horizontal directions, and calculates the convergence deformation of the tunnel in the vertical and horizontal directions by the difference between the spacings measured twice. The present invention is convenient, efficient, and accurate in data collection, and can monitor the convergence deformation of any section of the tunnel at any time. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 is a flow chart of the method of the present invention;

[0025] Figure 2 is a schematic diagram of marking points in an embodiment of the present invention;

[0026] Figure 3 is a schematic diagram of lining displacement calculation in an embodiment of the present invention;

[0027] Figure 4 is a schematic diagram of measuring the inner wall of the tunnel lining before deformation in an embodiment of the present invention;

[0028] Figure 5 It is a schematic diagram of measuring the inner wall of the tunnel lining after deformation in an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Figure 1 It is a flow chart of the method of the present invention, such as Figure 1 As shown, the method of this embodiment may include:

[0031] S1. Four marking points are evenly arranged on the inner wall of the tunnel lining to which the monitored section belongs. The monitored section is perpendicular to the tunnel axis.

[0032] S2. Determine a collection cycle, collect the marking point data of the inner wall of the tunnel lining by three-dimensional laser scanning every collection cycle, and process the collected marking point data;

[0033] S3, calculating the centroid coordinates of the monitored section at different periods according to the processed marking point data;

[0034] S4. Calculate the displacement of the monitored section according to the centroid coordinates at different periods;

[0035] S5. According to the centroid coordinates at different periods, calculate the vertical and horizontal spacing of the inner wall of the lining of the monitored section at different periods. According to the vertical and horizontal spacing at different periods, calculate the vertical and horizontal convergence deformation of the monitored section, and feed back the displacement, vertical convergence deformation and horizontal convergence deformation of the monitored section to the staff.

[0036] Based on the above scheme, the present invention provides a circular tunnel section displacement and convergence deformation monitoring method, which collects three-dimensional coordinate data of the inner wall of the tunnel lining to obtain point cloud data at different times. The centroid coordinates of the same section at different times are calculated respectively, and the overall displacement of the tunnel section is calculated using the change of the centroid coordinates. The present invention has high implementation efficiency and high accuracy, and can monitor the displacement of the target tunnel section at different times, providing technical support for tunnel construction and operation and maintenance; by measuring the vertical and horizontal spacing of the inner wall of the lining, the vertical and horizontal convergence deformation of the tunnel is calculated by the difference in the spacing between the two measurements. The present invention is convenient, efficient, and accurate in data collection, and can monitor the convergence deformation of any section of the tunnel at any time.

[0037] Specifically, this embodiment provides the details of the method, including:

[0038] S1. Evenly arrange 4 marking points on the inner wall of the tunnel lining of the monitored section, such as Figure 2 As shown, the monitored section is perpendicular to the tunnel axis, and the marking point is a physical mark that is easy to identify and permanently fixed to the inner wall of the tunnel. Specifically, the marking point adopts a physical mark that is durable, easy to identify and permanently fixed to the inner wall of the tunnel. The marking point is arranged on the inner wall of the tunnel lining of the monitored section. The monitored section is perpendicular to the tunnel axis, and it should be ensured that the marking point does not affect the normal use function of the tunnel;

[0039] S2. Determine the collection cycle, collect the marked point data of the inner wall of the tunnel lining by three-dimensional laser scanning every collection cycle, and ensure that the scanning range covers the monitored section; process the collected marked point data, specifically, perform registration and denoising on the marked point data collected by scanning, i.e., point cloud data, register adjacent measuring stations using target balls, and use different methods to filter and denoise the noise points that affect the data accuracy, specifically including: for ordered point cloud data, use standard Gaussian method and average method for filtering and denoising; for scattered point cloud data, mainly containing clumping noise and isolated point noise, use the K-neighborhood method of discrete points for filtering and denoising on the basis of grid network topology reconstruction;

[0040] S3. Calculate the centroid coordinates of the monitored section at different periods according to the processed marking point data; the calculation of the centroid coordinates of the monitored section at different periods includes calculating the centroid coordinates of period t according to formulas (1) and (2):

[0041]

[0042] in, represents the abscissa of the cross-section centroid at period t, represents the ordinate of the centroid of the section at period t, A represents the area of ​​the section at period t, f(x,y) represents the density function of the region where the section is located at period t, χ represents the abscissa of the area unit dA at period t, y represents the ordinate of the area unit dA at period t, and Ω represents the area domain of the tunnel section at period t.

[0043] S4. Calculate the displacement of the monitored section according to the centroid coordinates at different times, such as Figure 3 As shown;

[0044] S4 includes calculating the overall lateral displacement of the cross section according to formula (3), calculating the overall longitudinal displacement of the cross section according to formula (4), and calculating the overall displacement of the cross section according to formula (5).

[0045]

[0046]

[0047] Among them, X represents the overall lateral displacement of the section, Y represents the overall vertical displacement of the section, and Δ represents the overall displacement of the section. represents the abscissa of the centroid of the cross section after deformation, Represents the vertical coordinate of the centroid of the cross section after deformation.

[0048] Specifically, the calculation of centroid coordinates includes method 1: intercepting a point cloud slice of a certain width that contains the marked points of the monitored section, and calculating the centroid coordinates of the section; method 2: obtaining the point cloud data corresponding to the initial scan in this period, and placing the point cloud data of different periods in the same coordinate system, fitting the point cloud section, and calculating the centroid coordinates of the same section in different periods.

[0049] S5. According to the centroid coordinates at different times, calculate the vertical and horizontal spacing of the inner wall of the monitored section lining at different times. The horizontal spacing is the length of the line segment formed by the two points that intersect the centroid at time t and the boundary of the monitored section horizontally, and the longitudinal spacing is the length of the line segment formed by the two points that intersect the centroid at time t and the boundary of the monitored section vertically and vertically, such as Figure 4 As shown in the figure, the vertical and horizontal convergence deformation of the monitored section are calculated according to the vertical and horizontal spacing at different periods, as shown in the figure. Figure 5 The calculation of the vertical and horizontal convergence deformation of the monitored section according to the vertical and horizontal spacings at different periods includes calculating the vertical convergence deformation of the tunnel according to formula (6) and calculating the horizontal convergence deformation of the tunnel according to formula (7).

[0050] Δ v =D v ′-D v (6)

[0051] Δ h =D h ′-D h (7)

[0052] Among them, Δ v represents the vertical convergence deformation of the tunnel, Δ h represents the lateral convergence deformation of the tunnel, D v Indicates the vertical spacing of the sections before deformation, D h Indicates the transverse distance of the cross section before deformation, D v ′ represents the vertical spacing of the section after deformation, D h ′ represents the transverse spacing of the cross section after deformation.

[0053] Overall beneficial effects:

[0054] The present invention provides a circular tunnel section displacement and convergence deformation monitoring method, which collects three-dimensional coordinate data of the inner wall of the tunnel lining to obtain point cloud data at different times. The centroid coordinates of the same section at different times are calculated respectively, and the overall displacement of the tunnel section is calculated using the change of the centroid coordinates. The present invention has high implementation efficiency and high accuracy, and can monitor the displacement of the target tunnel section at different times, providing technical support for tunnel construction and operation and maintenance; by measuring the vertical and horizontal spacing of the inner wall of the lining, the vertical and horizontal convergence deformation of the tunnel is calculated by the difference in the spacing between the two measurements. The present invention is convenient, efficient, and accurate in data collection, and can monitor the convergence deformation of any section of the tunnel at any time.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for monitoring displacement and convergence deformation of a circular tunnel section, characterized in that: include: S1. Four marking points are evenly arranged on the inner wall of the tunnel lining to which the monitored section belongs. The monitored section is perpendicular to the tunnel axis. S2. Determine a collection cycle, collect the marking point data of the inner wall of the tunnel lining by three-dimensional laser scanning every collection cycle, and process the collected marking point data; S3, calculating the centroid coordinates of the monitored section at different periods according to the processed marking point data; S4. Calculate the displacement of the monitored section according to the centroid coordinates at different periods; S5. According to the centroid coordinates at different periods, the vertical and horizontal spacings of the inner wall of the lining of the monitored section at different periods are calculated. According to the vertical and horizontal spacings at different periods, the vertical and horizontal convergence deformations of the monitored section are calculated. The displacement, vertical convergence deformation and horizontal convergence deformation of the monitored section are fed back to the staff to realize the monitoring of the displacement and convergence deformation of the circular tunnel section.

2. A circular tunnel section displacement and convergence deformation monitoring method according to claim 1, characterized in that: The calculation of the centroid coordinates of the monitored section at different periods includes calculating the centroid coordinates of period t according to formulas (1) and (2): in, represents the abscissa of the cross-section centroid at period t, represents the vertical coordinate of the centroid of the section at period t, A represents the area of ​​the section at period t, f(x,y) represents the density function of the region where the section is located at period t, X represents the horizontal coordinate of the area unit dA at period t, y represents the vertical coordinate of the area unit dA at period t, and Ω represents the area domain of the tunnel section at period t.

3. A circular tunnel section displacement and convergence deformation monitoring method according to claim 2, characterized in that: S4 includes calculating the overall lateral displacement of the cross section according to formula (3), calculating the overall longitudinal displacement of the cross section according to formula (4), and calculating the overall displacement of the cross section according to formula (5). Among them, X represents the overall lateral displacement of the section, Y represents the overall vertical displacement of the section, and Δ represents the overall displacement of the section. represents the abscissa of the centroid of the cross section after deformation, Represents the vertical coordinate of the centroid of the cross section after deformation.

4. A circular tunnel section displacement and convergence deformation monitoring method according to claim 2, characterized in that: The calculation of the vertical and horizontal convergence deformation of the monitored section according to the vertical and horizontal spacings at different periods includes calculating the vertical convergence deformation of the tunnel according to formula (6) and calculating the horizontal convergence deformation of the tunnel according to formula (7). D v =D v ′-D v (6) D h =D h ′-D h (7) Among them, Δ v represents the vertical convergence deformation of the tunnel, Δ h represents the lateral convergence deformation of the tunnel, D v Indicates the vertical spacing of the monitored sections before deformation, D h Indicates the transverse distance of the monitored section before deformation, D v ′ represents the vertical spacing of the monitored sections after deformation, D h ′ represents the lateral spacing of the monitored section after deformation.

5. A circular tunnel section displacement and convergence deformation monitoring method according to claim 1, characterized in that: The marking point is a physical mark that is easy to identify and permanently fixed on the inner wall of the tunnel.

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