Shallow-buried tunnel deformation monitoring and early warning system and method

Abstract

The invention discloses a shallow tunnel deformation monitoring and early warning system and method, and the system comprises a first monitoring module which is used for monitoring the vault settlement amount and the peripheral convergence amount of a tunnel section; the second monitoring module is used for monitoring surrounding rock displacement at different measuring points in the tunnel section; the third monitoring module is arranged to be used for monitoring the settlement amount of different earth surface positions which are located on the same vertical plane with the tunnel section; and the early warning module is used for performing graded early warning on the tunnel deformation condition on the basis of the vault settlement data and the peripheral convergence data, and assisting in judging the deformation severity degree in the corresponding early warning grade by using the surrounding rock stability data. According to the method, the deformation condition of the current tunnel section is jointly judged through the monitoring data of the multiple monitoring modules located inside and outside the tunnel, graded and segmented early warning is achieved in combination with the vault settlement data, the peripheral convergence data and the surrounding rock stability data, and the comprehensiveness of tunnel deformation detection and the accuracy of early warning are effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of tunnel engineering monitoring, and more specifically, to a shallow tunnel deformation monitoring and early warning system and method. Background Art

[0002] During tunnel construction, blasting, excavation and other processes will have a great impact on the stability of the tunnel and surrounding rock, which may easily cause problems such as tunnel deformation and surface settlement, and there are great safety risks. Especially for shallow buried tunnels, due to their small burial depth, the tunnel construction below is more likely to affect the stability of the rock mass and soil layer above the full height range, causing accidents such as ground collapse and cave collapse, which will bring great safety risks to ground facilities, tunnels and construction personnel. Conventional tunnel safety monitoring methods mainly detect deformation inside the tunnel, and set safety thresholds for each deformation detection parameter for early warning. However, the selection of deformation detection parameters is usually relatively simple, such as the lateral and longitudinal displacement of each monitoring point. When the above deformation detection parameters are used for early warning, there are problems such as false alarms caused by detection errors and frequent or no response of the alarm mechanism due to improper setting of safety thresholds, which affect the accuracy of tunnel deformation detection and early warning, and thus affect the safety of tunnel construction.

[0003] In order to solve the above problems, it is necessary to design a shallow tunnel deformation monitoring and early warning system and method to improve the comprehensiveness of tunnel deformation detection and the accuracy of early warning. Summary of the invention

[0004] The purpose of the present invention is to provide a shallow buried tunnel deformation monitoring and early warning system and method, which jointly judges the deformation of the current tunnel section through the monitoring data of various monitoring modules located inside and outside the tunnel, and combines the vault settlement data, peripheral convergence data and surrounding rock stability data to achieve graded and classified early warning, thereby effectively improving the comprehensiveness of tunnel deformation detection and the accuracy of early warning.

[0005] In order to achieve these purposes and other advantages according to the present invention, a shallow tunnel deformation monitoring and early warning system is provided, comprising: A first monitoring module, which is configured to monitor the crown settlement and peripheral convergence of the tunnel section to be tested; A second monitoring module is configured to monitor the displacement of surrounding rocks at different measuring points within the same tunnel section; A third monitoring module is configured to monitor the settlement at different surface locations located in the same vertical plane as the tunnel section to be measured; A data processing module receives the monitoring data from the first monitoring module, the second monitoring module and the third monitoring module through the data transmission module and processes the monitoring data to obtain the vault settlement data, the peripheral convergence data and the surrounding rock stability data of the corresponding tunnel section; An early warning module is configured to receive data from the data processing module, to provide graded early warning of tunnel deformation based on the vault settlement data and the peripheral convergence data, and to use the surrounding rock stability data to assist in determining the severity of deformation within the corresponding early warning level.

[0006] Preferably, in the shallow tunnel deformation monitoring and early warning system, the first monitoring module comprises: A sinking monitoring device is arranged at the center of the vault of the tunnel section to be measured; Two convergence monitoring devices are relatively arranged at two ends of a set horizontal measuring line of the tunnel section to be measured; The sinking monitoring device and the convergence monitoring device both adopt a monitoring unit, which includes: a first detection rod, one end of which cooperates to pass through a first detection hole preset on the support layer and is anchored in the surrounding rock layer, and the other end extends outward from the first detection hole, and a grouting hole is provided at the outer end of the first detection rod, and the first detection rod is located on the side wall of the inner segment of the support layer and the surrounding rock layer, and grouting holes are provided at intervals, and each grouting hole is connected to the grouting hole through a grouting channel inside the first detection rod; a first reflection device, which is fixed on the outer side wall of the end of the first detection rod extending out of the first detection hole; A first total station is arranged on the tunnel floor and is used to measure the coordinates of the first reflection device of each monitoring unit.

[0007] Preferably, in the shallow tunnel deformation monitoring and early warning system, the monitoring unit also includes a protective shell, which is a hollow structure with a single-sided opening, wherein the opening is opposite to the orifice of the first detection hole and is fixed to the supporting layer by an anchor, the protective shell cover is arranged on the outer end of the first detection rod and the inner side wall is tightly fitted and pressed against the outer end face of the first detection rod, and an observation window is provided on the side of the protective shell adjacent to the first total station.

[0008] Preferably, in the shallow tunnel deformation monitoring and early warning system, the second monitoring module includes a plurality of second monitoring components, which are arranged on the inner wall of the tunnel at intervals along the contour line of the construction section to be measured, and any second monitoring component includes a second detection rod, which passes through a second detection hole preset in the support layer and the bottom end is anchored in the surrounding rock layer; a shell, which is a cylindrical structure with a T-shaped cross-section and closed at both ends, the tail part of the shell is fitted into the second detection hole and the tail end is slidably connected to the second detection rod, and the head part of the shell has a fixed cover arranged on the opening of the second detection hole and closes it; a pressure sensor, which is arranged on the inner side wall of the head of the shell opposite to the second detection rod; an elastic element, which fixedly connects the pressure sensor and the outer end of the second detection rod along the length direction of the second detection rod.

[0009] Preferably, in the shallow tunnel deformation monitoring and early warning system, the third monitoring module includes a plurality of third monitoring components, which are arranged at intervals along the tunnel width direction on the ground above the tunnel and are located in the same vertical plane as the tunnel section to be measured, and any third monitoring component includes a third detection rod, which passes through a third detection hole preset on the ground and has its bottom end anchored in the stratum below the third detection hole, and the top end of the third detection rod extends upward out of the third detection hole; a first filling layer, which is circumferentially arranged on the outside of the segment of the third detection rod located in the third detection hole and forms an annular casting layer; a second filling layer, which is filled between the first filling layer and the third detection hole and forms an annular casting layer; a second reflection device, which is fixed to the top of the outer wall of the third detection rod, and the three-dimensional coordinates of the third reflection device are measured by a second total station relatively arranged on one side of the third detection rod.

[0010] The present invention also provides an early warning method of the shallow tunnel deformation monitoring and early warning system, comprising the following steps: S1, reading the monitoring data of the first monitoring module, the second monitoring module, and the third monitoring module at the same frequency, processing the monitoring data at the same time, and obtaining the arch settlement data, peripheral convergence data, and surrounding rock stability data of the tunnel section to be measured; S2, setting the displacement thresholds of the crown settlement and the peripheral convergence in grades according to the distance between the tunnel section to be measured and the excavation surface, wherein the displacement thresholds of the crown settlement and the peripheral convergence decrease as the distance between the tunnel section to be measured and the excavation surface decreases; S3, the deformation of the tunnel is graded and warned according to the relationship between the amount of arch settlement, the amount of peripheral convergence and the corresponding displacement threshold. When the amount of arch settlement and the amount of peripheral convergence are greater than or equal to 2 / 3 of the corresponding displacement threshold, the warning module feeds back a second-level warning signal; when the amount of arch settlement and the amount of peripheral convergence are less than 2 / 3 of the corresponding displacement threshold and greater than or equal to 1 / 3 of the corresponding displacement threshold, the warning module feeds back a third-level warning signal; S4. When receiving the second-level warning signal, the control system outputs a construction suspension instruction and performs preliminary positioning and processing of the deformation position; When a third-level warning signal is received, the surrounding rock stability data at the same time is read, and the relationship between the surrounding rock displacement of the measuring point corresponding to each second monitoring module and the surface settlement of the measuring point corresponding to each third monitoring module and the corresponding control threshold is judged respectively. When the number of measuring points where the surrounding rock displacement or surface settlement exceeds 1 / 2 of the corresponding control threshold exceeds 70% of the total number of measuring points, the control system switches the third-level warning signal to a second-level warning signal for warning processing; otherwise, the control system automatically eliminates the third-level warning signal.

[0011] Preferably, the early warning method of the shallow tunnel deformation monitoring and early warning system, in S3, also includes early warning of the relative subsidence rate and relative convergence rate of the measuring points corresponding to the first monitoring module according to the tunnel burial depth. When the measured relative subsidence rate or relative convergence rate exceeds the set limit, a first-level early warning signal is directly fed back through the early warning module.

[0012] Preferably, the early warning method of the shallow tunnel deformation monitoring and early warning system, in S3, also includes early warning of the surrounding rock displacement of the measuring points corresponding to each second monitoring module and the surface settlement of the measuring points corresponding to each third monitoring module. When the surrounding rock displacement or surface settlement of any measuring point exceeds the set limit, a first-level early warning signal is directly fed back through the early warning module.

[0013] The present invention has at least the following beneficial effects: The present invention jointly judges the deformation of the current tunnel section through the monitoring data of various monitoring modules located inside and outside the tunnel, and realizes graded and classified early warning in combination with the arch settlement data, peripheral convergence data and surrounding rock stability data, thereby effectively improving the comprehensiveness of tunnel deformation detection and the accuracy of early warning.

[0014] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the structure of a monitoring unit of a shallow tunnel deformation monitoring and early warning system according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the second monitoring component in the above embodiment; Figure 3 is a schematic structural diagram of the third monitoring component described in the above embodiment; Figure 4 It is a schematic diagram of the arrangement structure of the multiple third monitoring components described in the above embodiment.

[0016] Description of reference numerals: 11. First detection rod; 12. Protective shell; 13. Anchor; 14. First reflection device; 2. Support layer; 3. Surrounding rock layer; 41. Second detection rod; 42. Shell; 43. Pressure sensor; 44. Elastic element; 5. Third monitoring component; 51. Third detection rod; 52. First filling layer; 53. Second filling layer; 54. Second reflection device; 6. Formation; 7. Tunnel. DETAILED DESCRIPTION

[0017] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0018] It should be noted that the experimental methods described in the following embodiments are conventional methods unless otherwise specified, and the reagents and materials are commercially available unless otherwise specified; in the description of the present invention, the terms "lateral", "longitudinal", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0019] like Figure 1-4 As shown, the present invention provides a shallow tunnel deformation monitoring and early warning system, comprising: A first monitoring module, which is configured to monitor the crown settlement and peripheral convergence of the tunnel section to be tested; A second monitoring module is configured to monitor the displacement of surrounding rocks at different measuring points within the same tunnel section; A third monitoring module is configured to monitor the settlement at different surface locations located in the same vertical plane as the tunnel section to be measured; A data processing module receives the monitoring data from the first monitoring module, the second monitoring module and the third monitoring module through the data transmission module and processes the monitoring data to obtain the vault settlement data, the peripheral convergence data and the surrounding rock stability data of the corresponding tunnel section; An early warning module is configured to receive data from the data processing module, to provide graded early warning of tunnel deformation based on the vault settlement data and the peripheral convergence data, and to use the surrounding rock stability data to assist in determining the severity of deformation within the corresponding early warning level.

[0020] In the above technical solution, the first monitoring module is set at the selected tunnel section feature points, specifically the center point of the vault of the tunnel section to be measured and the two ends of the preset horizontal measuring line. The second monitoring module and the third monitoring module both include multiple measuring points, and the multiple measuring points of the second monitoring module are evenly spaced on the tunnel section; the measuring points of the third monitoring module are located on the intersection of the tunnel section and the ground surface, and except for one measuring point arranged at the tunnel centerline, the remaining measuring points are symmetrically arranged on both sides of the tunnel centerline.

[0021] The data processing module and the early warning module can be integrated in the controller. The early warning module and the data processing module can transmit data through the built-in communication module of the controller; the controller and each monitoring module can transmit data through the data transmission module (cable / network port, etc.).

[0022] The warning logic of the early warning module is: the vault settlement data and the surrounding convergence data are used as the main monitoring data for control, and the current risk (warning) level is divided according to the size of the main monitoring data relative to its control value. When the main monitoring data exceeds the corresponding control value, the highest level of alarm is directly used for early warning. At this time, all construction actions in the current construction section need to be stopped to avoid causing tunnel safety accidents; when the main monitoring data does not exceed the corresponding control value, but there is a certain degree of fluctuation, other monitoring data (i.e., surrounding rock stability data) can be used to assist in judgment and execute corresponding early warning actions. Thus, the monitoring data of multiple monitoring modules are integrated to realize the hierarchical and classified processing of the early warning process, which largely avoids problems such as false alarms or insufficient early warning sensitivity caused by fluctuations in monitoring data.

[0023] In another technical solution, in the shallow tunnel deformation monitoring and early warning system, the first monitoring module includes: A sinking monitoring device is arranged at the center of the vault of the tunnel section to be measured; Two convergence monitoring devices are relatively arranged at two ends of a set horizontal measuring line of the tunnel section to be measured; The sinking monitoring device and the convergence monitoring device both adopt a monitoring unit, which includes: a first detection rod 11, one end of which cooperates to pass through a first detection hole preset on the supporting layer 2 and is anchored in the surrounding rock layer 3, and the other end extends outward from the first detection hole, and a grouting hole is provided at the outer end of the first detection rod 11, and the first detection rod 11 is located on the side wall of the inner segment of the supporting layer 2 and the surrounding rock layer 3, and grouting holes are provided at intervals, and each grouting hole is connected to the grouting hole through the grouting channel inside the first detection rod 11; a first reflection device 14, which is fixed on the outer side wall of the end of the first detection rod 11 extending out of the first detection hole; A first total station is arranged on the tunnel floor and is used to measure the coordinates of the first reflection device of each monitoring unit.

[0024] In the above technical solution, the first detection rod can be anchored in the surrounding rock layer and the supporting layer layer by layer by grouting different grouting holes. The first total station monitors the settlement and convergence displacement of the installation position of the corresponding monitoring unit by detecting the coordinate change of the center point of the first reflection device located at the outer end of the first detection rod. The first reflection device can use conventional measuring components such as reflective plates and reflective prisms. After the first detection rod is extended into the surrounding rock layer, grouting is firstly performed through the grouting hole to the (first detection rod) grouting hole located in the surrounding rock layer. At this time, concrete or mud with similar properties to the surrounding rock is used. After the pores of the surrounding rock are filled, the sprayed concrete used in the construction of the support layer is injected into the grouting hole located in the support layer, so that the first detection rod can be better connected with each layer of the tunnel structure, and the connection and detection stability of the monitoring unit are strengthened.

[0025] In another technical solution, in the shallow tunnel deformation monitoring and early warning system, the monitoring unit also includes a protective shell 12, which is a hollow structure with a single-sided opening, and its opening is opposite to the orifice of the first detection hole and is fixed to the support layer 2 by an anchor 13. The protective shell 12 is covered on the outer end of the first detection rod 11 and the inner side wall is tightly pressed against the outer end face of the first detection rod 11. An observation window is provided on the side of the protective shell 12 adjacent to the first total station.

[0026] The observation window is a detachable structure covering the range of the first reflector. When no measurement is performed, the protective shell forms a closed structure outside the first detection rod to protect the first detection rod. When measurement is required, the observation window can be opened to smoothly perform total station monitoring. The anchoring piece can be an anchor rod, which passes through the reserved perforation on the protective shell and is anchored into the supporting layer. The setting direction of the anchor rod is parallel to the axis of the first detection rod.

[0027] In another technical solution, in the shallow tunnel deformation monitoring and early warning system, the second monitoring module includes a plurality of second monitoring components, which are arranged on the inner wall of the tunnel at intervals along the contour line of the construction section to be measured, and any second monitoring component includes a second detection rod 41, which passes through a second detection hole preset on the support layer 2 and the bottom end is anchored in the surrounding rock layer 3; a shell 42, which is a cylindrical structure with a T-shaped cross-section and closed at both ends, the tail of the shell 42 is fitted into the second detection hole and the tail end is slidably connected to the second detection rod 41, and the head of the shell 42 is fixedly covered on the opening of the second detection hole and closes it; a pressure sensor 43, which is arranged on the inner side wall of the head of the shell 42 opposite to the second detection rod 41; an elastic element 44, which is fixedly connected between the pressure sensor 43 and the outer end of the second detection rod 41 along the length direction of the second detection rod 41.

[0028] The third monitoring module includes a plurality of third monitoring components 5, which are arranged at intervals along the tunnel width direction on the ground above the tunnel and are located in the same vertical plane as the tunnel section to be measured, and any third monitoring component 5 includes a third detection rod 51, which passes through a third detection hole preset on the ground and has its bottom end anchored in the stratum 6 below the third detection hole, and the top end of the third detection rod 51 extends upward from the third detection hole; a first filling layer 52, which is circumferentially arranged on the outside of the segment of the third detection rod 51 located in the third detection hole and forms an annular casting layer; a second filling layer 53, which is filled between the first filling layer 52 and the third detection hole and forms an annular casting layer; a second reflection device 54, which is fixed to the top of the outer wall of the third detection rod 51, and the three-dimensional coordinates of the third reflection device 54 are measured by a second total station relatively arranged on one side of the third detection rod 51.

[0029] In the above technical solution, the second monitoring component and the third monitoring component are arranged on the same vertical plane (where the tunnel section is located), each second monitoring component is used to measure the surrounding rock state near the current tunnel section from inside the tunnel 7, and each third monitoring component is used to indirectly measure the surrounding rock state near the current tunnel section from outside the tunnel 7 (surface). Although there is a certain (height) distance between the ground and the tunnel 7, for the shallow buried tunnel construction section, the settlement data of the surface position extending upward along the current tunnel section can also reflect the surrounding rock stability near the tunnel section. In actual construction, the staff can make a comprehensive judgment on the surrounding rock stability at the current tunnel section by combining the monitoring results of the second monitoring component and the third monitoring component.

[0030] Specifically, the second monitoring component is installed after the construction of the supporting layer is completed. A second detection hole is preset at the installation position of the second monitoring component. The shell can be inserted into and close the second detection hole from the outside, so that, based on the second detection hole, an independent and closed detection space that is not interfered by the external environment is formed inside the shell. One end of the second detection rod is located inside the above-mentioned detection space, and the other end (slides) passes through the tail end (bottom end) of the shell and then penetrates into the surrounding rock layer and is fixed thereto. When the surrounding rock layer is disturbed, its disturbance can be fed back by the displacement of the second detection rod in the detection space. An elastic element and a pressure sensor are also provided between the second detection rod and the head of the shell, wherein the reading of the pressure sensor can not only feed back the pressure change in the surrounding rock layer, but also calculate the deformation of the elastic element according to the elastic coefficient, and then feed back the magnitude of the disturbance amplitude in the surrounding rock layer. The elastic element can be a spring. The head of the shell can be fixed at the opening of the second detection hole by an anchor rod, which isolates the interference of the support layer structure on the one hand and forms an independent detection space for the second detection rod; on the other hand, the shell and the tunnel support layer can form a relatively stable overall connection structure, providing a stable reference surface for the detection stroke of the second detection rod, ensuring the accuracy of the detection data. When arranging, each second monitoring component should avoid the steel frame and the empty backfill, arrange the monitoring point between the two steel frames, and the bottom end of the second detection rod should be driven into the surrounding rock to a depth of not less than 30cm.

[0031] The multiple third monitoring components are arranged symmetrically on both sides of the tunnel centerline except for the tunnel centerline position, and the spacing between the two third monitoring components located at the outermost ends is not less than H0+B, where H0 is the tunnel burial depth and B is the tunnel design width. The spacing between two adjacent third monitoring components can be controlled at 2m~5m, and the spacing can be appropriately shortened near the position close to the tunnel centerline. The influence of the surface settlement data measured by the third monitoring components at different positions on the stability of the surrounding rock in different areas around the tunnel section can be determined according to the tunnel force analysis structure, and the control threshold of each third monitoring component can be set based on this. The third monitoring component detects the displacement (change in height coordinate) of the second reflection device through the second total station, and can realize the detection of the displacement of the third detection rod as the stratum settles. Among them, the first filling layer is a concrete casting layer, which is used to connect the third detection rod with the bottom formation structure as an integral whole; the second filling layer is a grouting filling layer of cement and clay, which is used to further better connect the third detection rod and the first filling layer with the surrounding formation structure as an integral whole. Therefore, when the formation structure changes, its settlement situation can be accurately fed back by the displacement of the end of the third detection rod extending out of the third detection hole.

[0032] The second inspection rod and the third inspection rod may also be provided with corresponding grouting channels connected up and down inside. Thus, after the second inspection rod and the third inspection rod are respectively anchored in the corresponding soil layer / rock layer at the bottom of the hole, the connection strength and stability between each inspection rod and the corresponding deep formation of the inspection hole can be further strengthened by grouting.

[0033] The present invention also provides an early warning method of the shallow tunnel deformation monitoring and early warning system, comprising the following steps: S1, reading the monitoring data of the first monitoring module, the second monitoring module, and the third monitoring module at the same frequency, processing the monitoring data at the same time, and obtaining the arch settlement data, peripheral convergence data, and surrounding rock stability data of the tunnel section to be measured; S2, setting the displacement thresholds of the crown settlement and the peripheral convergence in grades according to the distance between the tunnel section to be measured and the excavation surface, wherein the displacement thresholds of the crown settlement and the peripheral convergence decrease as the distance between the tunnel section to be measured and the excavation surface decreases; S3, the deformation of the tunnel is graded and warned according to the relationship between the amount of arch settlement, the amount of peripheral convergence and the corresponding displacement threshold. When the amount of arch settlement and the amount of peripheral convergence are greater than or equal to 2 / 3 of the corresponding displacement threshold, the warning module feeds back a second-level warning signal; when the amount of arch settlement and the amount of peripheral convergence are less than 2 / 3 of the corresponding displacement threshold and greater than or equal to 1 / 3 of the corresponding displacement threshold, the warning module feeds back a third-level warning signal; S4. When receiving the second-level warning signal, the control system outputs a construction suspension instruction and performs preliminary positioning and processing of the deformation position; When a third-level warning signal is received, the surrounding rock stability data at the same time is read, and the relationship between the surrounding rock displacement of the measuring point corresponding to each second monitoring module and the surface settlement of the measuring point corresponding to each third monitoring module and the corresponding control threshold is judged respectively. When the number of measuring points where the surrounding rock displacement or surface settlement exceeds 1 / 2 of the corresponding control threshold exceeds 70% of the total number of measuring points, the control system switches the third-level warning signal to a second-level warning signal for warning processing; otherwise, the control system automatically eliminates the third-level warning signal.

[0034] In the above technical solution, in S3, when the amount of arch settlement or the amount of peripheral convergence is greater than or equal to the corresponding displacement threshold, a first-level warning signal is fed back through the early warning module, and the control system outputs an emergency stop signal to stop the construction work in the entire range, and continue the construction after the hidden danger is eliminated. When the amount of arch settlement and the amount of peripheral convergence are both greater than or equal to 2 / 3 of the corresponding displacement threshold, a second-level warning signal is fed back through the early warning module; when only one of the monitored amounts of arch settlement and peripheral convergence is greater than or equal to 2 / 3 of the corresponding displacement threshold (but not exceeding the displacement threshold), a third-level warning signal is fed back. When both the amount of arch settlement and the amount of peripheral convergence are greater than or equal to 1 / 3 of the corresponding displacement threshold (and less than 2 / 3 of the corresponding displacement threshold), a third-level warning signal is fed back through the early warning module; when only one of the monitored amounts is greater than or equal to 1 / 3 of the corresponding displacement threshold, no early warning processing is performed.

[0035] In S4, when the deformation degree is determined by the surrounding rock stability data, the total number of measuring points is the total number of similar measuring points, that is, the number of measuring points corresponding to the second monitoring module or the number of measuring points corresponding to the third monitoring module. Different measuring points are preset with different control thresholds according to their setting positions (height, distance from the tunnel centerline), and the corresponding control thresholds need to be selected for comparison during judgment.

[0036] In another technical solution, the early warning method of the shallow tunnel deformation monitoring and early warning system, in S3, also includes early warning of the relative subsidence rate and relative convergence rate of the corresponding measuring point of the first monitoring module according to the tunnel burial depth. When the measured relative subsidence rate or relative convergence rate exceeds the set limit, the first-level early warning signal is directly fed back through the early warning module.

[0037] S3 also includes early warning of the surrounding rock displacement at the measuring points corresponding to each second monitoring module and the surface settlement at the measuring points corresponding to each third monitoring module. When the surrounding rock displacement or surface settlement at any measuring point exceeds the set limit, a first-level early warning signal is directly fed back through the early warning module.

[0038] Among them, single-level warnings are given for the relative subsidence rate, relative convergence rate, surrounding rock displacement and surface settlement respectively.

[0039] The control thresholds (set limits) of the relative subsidence rate and relative convergence rate need to be set according to the tunnel burial depth. The smaller the tunnel burial depth, the smaller the control thresholds of the relative subsidence rate and relative convergence rate.

[0040] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A shallow tunnel deformation monitoring and early warning system, characterized in that: include: A first monitoring module, which is configured to monitor the crown settlement and peripheral convergence of the tunnel section to be tested; A second monitoring module is configured to monitor the displacement of surrounding rocks at different measuring points within the same tunnel section; A third monitoring module is configured to monitor the settlement at different surface locations located in the same vertical plane as the tunnel section to be measured; A data processing module receives the monitoring data from the first monitoring module, the second monitoring module and the third monitoring module through the data transmission module and processes the monitoring data to obtain the vault settlement data, the peripheral convergence data and the surrounding rock stability data of the corresponding tunnel section; An early warning module is configured to receive data from the data processing module, to provide graded early warning of tunnel deformation based on the vault settlement data and the peripheral convergence data, and to use the surrounding rock stability data to assist in determining the severity of deformation within the corresponding early warning level.

2. The shallow tunnel deformation monitoring and early warning system according to claim 1, characterized in that: The first monitoring module includes: A sinking monitoring device is arranged at the center of the vault of the tunnel section to be measured; Two convergence monitoring devices are relatively arranged at two ends of a set horizontal measuring line of the tunnel section to be measured; The sinking monitoring device and the convergence monitoring device both adopt a monitoring unit, which includes: a first detection rod, one end of which cooperates to pass through a first detection hole preset on the support layer and is anchored in the surrounding rock layer, and the other end extends outward from the first detection hole, and a grouting hole is provided at the outer end of the first detection rod, and the first detection rod is located on the side wall of the inner segment of the support layer and the surrounding rock layer, and grouting holes are provided at intervals, and each grouting hole is connected to the grouting hole through a grouting channel inside the first detection rod; a first reflection device, which is fixed on the outer side wall of the end of the first detection rod extending out of the first detection hole; A first total station is arranged on the tunnel floor and is used to measure the coordinates of the first reflection device of each monitoring unit.

3. The shallow tunnel deformation monitoring and early warning system according to claim 2, characterized in that: The monitoring unit also includes a protective shell, which is a hollow structure with a single-sided opening, the opening of which is opposite to the orifice of the first detection hole and is fixed to the supporting layer by an anchor. The protective shell cover is arranged on the outer end of the first detection rod and the inner side wall is tightly fitted and pressed against the outer end surface of the first detection rod. An observation window is provided on the side of the protective shell adjacent to the first total station.

4. The shallow tunnel deformation monitoring and early warning system according to claim 1, characterized in that: The second monitoring module includes a plurality of second monitoring components, which are arranged at intervals on the inner wall of the tunnel along the contour line of the construction section to be measured, and any second monitoring component includes a second detection rod, which passes through a second detection hole preset on the supporting layer and the bottom end of which is anchored in the surrounding rock layer; a shell, which is a cylindrical structure with a T-shaped cross-section and closed at both ends, the tail of the shell is fitted into the second detection hole and the tail end is slidably connected to the second detection rod, and the head of the shell is fixedly covered on the opening of the second detection hole and closes it; a pressure sensor is arranged on the inner side wall of the head of the shell opposite to the second detection rod; an elastic element is fixedly connected to the pressure sensor and the outer end of the second detection rod along the length direction of the second detection rod.

5. The shallow tunnel deformation monitoring and early warning system according to claim 1, characterized in that: The third monitoring module includes multiple third monitoring components, which are arranged on the ground above the tunnel at intervals along the tunnel width direction and are located in the same vertical plane as the tunnel section to be measured, any third monitoring component includes a third detection rod, which passes through a third detection hole preset on the ground and has its bottom end anchored in the stratum below the third detection hole, and the top of the third detection rod extends upward out of the third detection hole; a first filling layer, which is circumferentially arranged on the outside of the segment of the third detection rod located in the third detection hole and forms an annular casting layer; a second filling layer, which is filled between the first filling layer and the third detection hole and forms an annular casting layer; a second reflection device, which is fixed on the top of the outer wall of the third detection rod, and the three-dimensional coordinates of the third reflection device are measured by a second total station relatively arranged on one side of the third detection rod.

6. An early warning method for a shallow tunnel deformation monitoring and early warning system as claimed in claim 1, characterized in that: The following steps are involved: S1, reading the monitoring data of the first monitoring module, the second monitoring module, and the third monitoring module at the same frequency, processing the monitoring data at the same time, and obtaining the arch settlement data, peripheral convergence data, and surrounding rock stability data of the tunnel section to be measured; S2, setting the displacement thresholds of the crown settlement and the peripheral convergence in grades according to the distance between the tunnel section to be measured and the excavation surface, wherein the displacement thresholds of the crown settlement and the peripheral convergence decrease as the distance between the tunnel section to be measured and the excavation surface decreases; S3, the deformation of the tunnel is graded and warned based on the relationship between the arch settlement, the surrounding convergence and the corresponding displacement threshold. When the arch settlement and the surrounding convergence are greater than or equal to 2 / 3 of the corresponding displacement threshold, a secondary warning signal is fed back through the warning module; When the vault settlement and the peripheral convergence are less than 2 / 3 of the corresponding displacement threshold and greater than or equal to 1 / 3 of the corresponding displacement threshold, a third-level warning signal is fed back through the warning module; S4. When receiving the second-level warning signal, the control system outputs a construction suspension instruction and performs preliminary positioning and processing of the deformation position; When a third-level warning signal is received, the surrounding rock stability data at the same time is read, and the relationship between the surrounding rock displacement of the measuring point corresponding to each second monitoring module and the surface settlement of the measuring point corresponding to each third monitoring module and the corresponding control threshold is judged respectively. When the number of measuring points where the surrounding rock displacement or surface settlement exceeds 1 / 2 of the corresponding control threshold exceeds 70% of the total number of measuring points, the control system switches the third-level warning signal to a second-level warning signal for warning processing; otherwise, the control system automatically eliminates the third-level warning signal.

7. The early warning method of the shallow tunnel deformation monitoring and early warning system according to claim 6, characterized in that: S3 also includes issuing early warnings for the relative subsidence rate and relative convergence rate of the corresponding measuring points of the first monitoring module according to the tunnel burial depth. When the measured relative subsidence rate or relative convergence rate exceeds the set limit, a first-level early warning signal is directly fed back through the early warning module.

8. The early warning method of the shallow tunnel deformation monitoring and early warning system according to claim 6, characterized in that: S3 also includes early warning of the surrounding rock displacement at the measuring points corresponding to each second monitoring module and the surface settlement at the measuring points corresponding to each third monitoring module. When the surrounding rock displacement or surface settlement at any measuring point exceeds the set limit, a first-level early warning signal is directly fed back through the early warning module.

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