A system and method for monitoring displacement of surrounding rock in advanced tunnel

Abstract

The present invention provides a system for monitoring displacement of surrounding rock in an advanced tunnel, comprising: a plurality of radiation source advance boreholes drilled in the surrounding rock in front of the tunnel excavation working face; four radar advance boreholes drilled adjacent to the plurality of radiation source advance boreholes; a radiation source unit comprising a plurality of targets, a plurality of constant temperature resistors, a plurality of external wirings, and an integrated power supply and temperature control unit; a radar positioning unit comprising a central station radar, a 1# auxiliary station radar, a 2# auxiliary station radar, and a 3# auxiliary station radar; and a digital display unit comprising an external port, a data processing and storage module, a display screen, a data transmission interface, and a power supply. The present invention also provides a method for monitoring displacement of surrounding rock in an advanced tunnel. The present invention utilizes a plurality of targets buried in the tunnel surrounding rock and a passive distributed radar system, and utilizes the heat-generating targets as radiation sources. The passive distributed radar system receives electromagnetic wave signals from the radiation sources, enabling continuous monitoring of the displacement of each target buried in the tunnel surrounding rock in three dimensions.

Description

Technical Field

[0001] The present invention relates to the technical field of geotechnical engineering tunnel excavation and monitoring, and in particular to a system and method for monitoring displacement of surrounding rocks in an advanced tunnel. Background Art

[0002] The excavation and support of tunnels or roadways are involved in fields such as municipal engineering, transportation engineering, water conservancy engineering, and mining engineering. Whether it is a shallow tunnel or a deep underground roadway, the excavation process will disturb the surrounding rock, destroy its stability, and then change the original stress state of the surrounding rock, causing deformation. In severe cases, it will cause roadway surrounding rock accidents. To this end, it is necessary to take certain support measures for the tunnel or roadway surrounding rock in a timely manner to restore its stability as soon as possible. The choice of tunnel or roadway support method is closely related to the deformation, displacement and other change patterns of the surrounding rock. Therefore, timely grasp of the deformation, displacement and other data of the surrounding rock and their change patterns can make scientific judgments on the support, deformation, convergence and stability of the surrounding rock, so as to take reasonable countermeasures, greatly reduce the incidence of surrounding rock accidents and protect the lives of construction workers.

[0003] At present, the devices used for the displacement of tunnel or roadway surrounding rock are mainly multi-point displacement meters, roof separation meters, etc. These monitoring instruments are installed in the roadway surrounding rock after the roadway is excavated, that is, these monitoring instruments have a certain "lag" and only monitor the displacement of the surrounding rock after the roadway is excavated. It is impossible to achieve continuous monitoring of the displacement of the surrounding rock before, during and after the roadway excavation, and thus it is impossible to fully understand the changing law of the surrounding rock displacement before and after the roadway excavation; at the same time, the existing monitoring instruments can only monitor the displacement of the surrounding rock in one direction, while under actual conditions the displacement of the surrounding rock moves in three-dimensional space. It can be seen that the current related displacement monitoring has certain limitations; in addition, the operating steps of these monitoring instruments during installation are very complicated and the monitoring cost is high. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a system and method for monitoring displacement of surrounding rock in an advanced roadway.

[0005] In order to achieve the above-mentioned object, the present invention adopts the following technical solution: a system for monitoring displacement of surrounding rock in an advanced roadway, comprising:

[0006] Multiple radiation source advance drill holes are drilled in the surrounding rock in front of the tunnel excavation working face, and four radar advance drill holes are drilled next to the multiple radiation source advance drill holes.

[0007] The radiation source unit includes multiple targets, multiple constant temperature resistors, multiple external wirings, and a power supply and temperature control integrated device. Each target is provided in each radiation source advance borehole. Each target is provided with a constant temperature resistor. Each constant temperature resistor is connected to the power supply and temperature control integrated device located outside the radiation source advance borehole via an external wiring. The power supply and temperature control integrated device is used to control the temperature of the constant temperature resistor in each target. The target and the constant temperature resistor are pushed to the bottom of the radiation source advance borehole via the radiation source pushing and mounting unit.

[0008] The radar positioning unit includes a central station radar, a No. 1 auxiliary station radar, a No. 2 auxiliary station radar, and a No. 3 auxiliary station radar. The central station radar, No. 1 auxiliary station radar, No. 2 auxiliary station radar, and No. 3 auxiliary station radar are respectively pushed to the bottom of the four radar advance boreholes via a radar pushing and installation unit. The No. 1 auxiliary station radar, No. 2 auxiliary station radar, and No. 3 auxiliary station radar monitor the displacement of multiple targets in real time and transmit the data to the central station radar. The central station radar is connected to a data cable, and a data cable plug is provided at the end of the data cable.

[0009] The digital display unit includes an external port, a data processing and storage module, a display screen, a data transmission interface and a power supply. The data cable plug is connected to the external port. The data processing and storage module is used to calculate and process the data transmitted by the central station radar and store the processed data; the display screen is used to display data information; the data transmission interface is used to connect to an external device and transmit the stored data to the external device; the power supply is used to power the data processing and storage module and the display screen.

[0010] Furthermore, the target body includes a metal circular shell with a hollow structure inside. A first threaded connection hole is opened on the metal circular shell, and a wire hole is opened next to the first threaded connection hole. The constant temperature resistor is fixed inside the metal circular shell, and the external wire on the constant temperature resistor passes through the wire hole.

[0011] Furthermore, the power supply and temperature control integrated machine includes a shell, a battery, a temperature controller, a temperature adjustment knob and a switch. The shell is provided with a battery and a temperature controller, and the shell is provided with a temperature adjustment knob and a switch. The temperature adjustment knob is connected to the temperature controller. The shell is also provided with multiple external holes. The external wires on the constant temperature resistor in each target body are respectively connected to the battery through the external holes. The battery and the temperature controller are also connected separately, the temperature adjustment knob is connected to the temperature controller, and the switch is connected to the power supply.

[0012] Furthermore, the central station radar includes a first shuttle-shaped shell, in which the central station radar body is fixed, and a second threaded connection hole is opened at the end of the first shuttle-shaped shell, and the central station radar body is connected to the data line, and the data line passes through the second threaded connection hole;

[0013] The 1# auxiliary station radar, 2# auxiliary station radar and 3# auxiliary station radar have the same structure and all include a second shuttle-shaped shell, in which the auxiliary station radar body is fixed, and a third threaded connection hole is opened at the end of the second shuttle-shaped shell.

[0014] Furthermore, the radiation source pushing and installation unit includes multiple solid connecting rods, a polyurethane sealing part, a grouting pipe and a grouting pump. After the multiple solid connecting rods are threadedly connected in sequence, the first solid connecting rod is connected to the target body, and the target body is pushed to the bottom of the radiation source advance drilling hole. The polyurethane sealing part is formed at the mouth of the radiation source advance drilling hole by polyurethane sealing. The front end of the grouting pipe passes through the polyurethane sealing part and is placed inside the radiation source advance drilling hole. The end of the grouting pipe is connected to the grouting pump, and the cement mortar is injected into the radiation source advance drilling hole through the grouting pipe by the grouting pump.

[0015] Furthermore, the radar pushing and installation unit includes a high-pressure expansion capsule sealer, multiple hollow connecting rods, a manual pressure pump, a high-pressure liquid injection pipe and a pressure relief device. The multiple hollow connecting rods are connected in sequence by threads. The front end of the high-pressure expansion capsule sealer is threadedly connected to the central station radar, 1# auxiliary station radar, 2# auxiliary station radar or 3# auxiliary station radar. The end of the high-pressure expansion capsule sealer is threadedly connected to the first hollow connecting rod. The end of the high-pressure expansion capsule sealer is also connected to one end of the high-pressure liquid injection pipe. The other end of the high-pressure liquid injection pipe is connected to the pressure relief device, and the pressure relief device is connected to the manual pressure pump.

[0016] Furthermore, the high-pressure expansion capsule sealer includes a central tube and an expansion capsule, the central tube being a cylindrical tube body with closed ends and having a cavity inside, the tube wall of the central tube being a double-layer structure, including an inner tube wall and an outer tube wall, the inner tube wall and the outer tube wall being a hollow structure, and a plurality of liquid outlet holes are opened axially on the outer tube wall, the expansion capsule is wrapped around the outer circumferential surface of the outer tube wall, a first connecting tube and a second connecting tube are axially provided at the center of the left end face and the right end face of the central tube respectively, the interiors of the first connecting tube and the second connecting tube are both hollow structures, through holes are provided on the left end face and the right end face of the central tube at positions corresponding to the first connecting tube and the second connecting tube respectively, the first connecting tube and the second connecting tube are connected with the internal cavity of the central tube through the through holes, threaded connection sections are provided on the first connecting tube and the second connecting tube respectively, and a liquid inlet is provided on the right end face of the central tube between the inner tube wall and the outer tube wall, the liquid inlet is used to connect with the high-pressure injection pipe.

[0017] Furthermore, a wire hole is provided on the second connecting tube. The data cable and data cable plug connected to the central station radar body pass through the first connecting tube, the internal cavity of the central tube, and the second connecting tube in sequence, and finally pass through the wire hole and pass through the radar advance drilling. The data cable plug is connected to the digital display unit.

[0018] The present invention also provides a method for monitoring displacement of surrounding rock in an advanced roadway, which is implemented using the aforementioned system for monitoring displacement of surrounding rock in an advanced roadway and specifically includes the following steps:

[0019] S1, monitoring scheme design: according to the current status of the tunnel excavation working face, design the number of targets in the radiation source unit, the layout of each target, and the layout of the central station radar, 1# auxiliary station radar, 2# auxiliary station radar and 3# auxiliary station radar in the radar positioning unit;

[0020] S2, advance drilling construction: Radiation source advance drilling and radar advance drilling construction. According to the above-mentioned design parameters, a drilling rig is used to construct radiation source advance drilling and radar advance drilling on the roadway wall along the excavation direction of the roadway excavation working face. The drilling depth is determined by the specific layout of the designed target object and radar positioning unit. During the drilling process, different rock layers are cored and processed into rock samples;

[0021] S3, laboratory experiment: The processed rock samples were placed in a laboratory constant temperature chamber to maintain the same temperature as the surrounding rock of the on-site tunnel. A target body equipped with a constant temperature resistor was then placed in rock samples from different rock formations. The temperature of the constant temperature resistor was controlled by a power supply and temperature controller. The propagation speed and attenuation rate of thermal radiation generated by the target body in the rock samples from different rock formations under different temperature conditions were measured. The temperatures were set at 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, and 90°C.

[0022] Conduct 3-5 measurements on rock samples of each rock layer, and compare and analyze the measurement results to determine the temperature value of the thermal radiation generated by the target body at the optimal propagation speed and attenuation rate;

[0023] S4, radiation source unit and radar positioning unit installation:

[0024] Each target object is pushed to the bottom of the radiation source advance drilled hole by the radiation source pushing installation unit, and a polyurethane sealing portion is formed at the opening of each radiation source advance drilled hole by polyurethane sealing, and the front end of the grouting pipe is passed through the polyurethane sealing portion and placed inside the radiation source advance drilled hole, and the end of the grouting pipe is connected to the grouting pump, and the cement mortar is injected into the radiation source advance drilled hole through the grouting pipe by the grouting pump;

[0025] Push the central station radar, No. 1 auxiliary station radar, No. 2 auxiliary station radar, and No. 3 auxiliary station radar to the bottom of the radar advance borehole through the radar pushing and installation unit, and start the manual pressure pump to input high-pressure liquid into the expansion capsule sealer to expand the expansion capsule to seal the hole;

[0026] S5, system trial operation: connect the external wiring of each target body to the power supply and temperature control integrated machine, and adjust the temperature value of the constant temperature resistor according to the actual surrounding rock temperature on site through the power supply and temperature control integrated machine according to the surrounding rock temperature outside each target body;

[0027] Connect the central station radar to the data cable, and connect the data cable plug at the end of the data cable to the external port of the digital display unit to monitor and view the position of each target;

[0028] S6, surrounding rock displacement monitoring: As the tunnel continues to advance, the target objects inside the tunnel surrounding rock will move with the changes in the tunnel surrounding rock. The displacement data will be monitored by the 1#, 2# and 3# auxiliary station radars and stored in the digital display unit.

[0029] According to the actual needs on site, when the tunnel excavation working face exceeds each target body and when the displacement data of each target body no longer changes, the monitoring can be ended;

[0030] S7, device recovery:

[0031] After the monitoring is completed, the digital display unit is first removed and preserved so that it can be brought to the ground and its internal data is connected to the external device through the data transmission interface, and the data is imported into the external device for analysis; then each radar push installation unit is depressurized and the central station radar, 1# auxiliary station radar, 2# auxiliary station radar and 3# auxiliary station radar are gradually taken out, and the radar advance drilling holes are sealed after taking them out; at the same time, the power supply and temperature control integrated machine is recycled for next use.

[0032] Furthermore, in step S1, the number of target bodies of the radiation source unit is 9, which are arranged in the surrounding rock on the right side of the roadway and the surrounding rock on the roof to monitor the displacement of the surrounding rock on the right side of the roadway and the surrounding rock on the roof. The specific arrangement positions are:

[0033] There are five targets arranged in a straight line on the right side of L9 in front of the tunnel working face, with L9 = 5m-8m. The spacing between the targets is L2, L2 = 0.5m-1.0m, and the height of each target from the tunnel floor is L8, L8 = 0.5m-2.0m. The first target is located on the right side of the right side of the tunnel, and its distance from the right side of the tunnel is L1, L1 = 0.5m-2.0m.

[0034] At the same time, at a distance of L9 in front of the tunnel excavation working face, four target bodies are arranged vertically upward along the center of the tunnel excavation working face, and the spacing between each target body is L4, L4 = 1.0m-2.0m.

[0035] The first target body located above the arched roof of the tunnel has a distance L3 from the highest point of the arched roof of the tunnel, where L3 = 0.5m-2.0m;

[0036] The central station radar, 1# auxiliary station radar, 2# auxiliary station radar and 3# auxiliary station radar in the radar positioning unit are arranged in an inverted "Y" shape on the right side of the five targets. The heights of 1# auxiliary station radar and 2# auxiliary station radar are equal, and the height from the roadway floor is equal to the height L8 of the five targets. The distance between 1# auxiliary station radar and 2# auxiliary station radar is L 12 , L 12 = 2.0m-5.0m, the central station radar and the 3# auxiliary station radar are located above the center of the line connecting the 1# auxiliary station radar and the 2# auxiliary station radar, respectively. The distance between the central station radar and the 1# auxiliary station radar and the 2# auxiliary station radar is L6, L6 = 1.0m-5.0m, the distance between the 3# auxiliary station radar and the central station radar is L7, L7 = 0.5m-4.0m, the extended line connecting the five targets intersects and is perpendicular to the center of the line connecting the 1# auxiliary station radar and the 2# auxiliary station radar; the distance between the line connecting the 1# auxiliary station radar and the 2# auxiliary station radar and the last target located on the right side of the right side of the tunnel is L5, L5 = 2m-3m;

[0037] In step S2, the radiation sources of the five target bodies arranged in the surrounding rock on the right side of the tunnel are placed in the same position for the advanced drilling holes, and are located at a distance of L from the tunnel excavation working face. 10 On the right side of the rear tunnel; the radiation source of the four target bodies arranged in the tunnel arch roof surrounding rock has the same position of the advanced drilling hole, and is located at a distance of L from the tunnel excavation working face. 10 At the center of the arched roof of the rear tunnel, L 10 =5m-8m;

[0038] The radar advance drilling opening positions of the central station radar, 1# auxiliary station radar, 2# auxiliary station radar and 3# auxiliary station radar are located on the right side of the tunnel and L behind the radiation source advance drilling opening positions of the five target bodies in the surrounding rock on the right side of the tunnel. 11 Within the range, L 11 =1.0m-3.0m.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] 1. The present invention utilizes multiple targets embedded in the tunnel surrounding rock and a passive distributed radar system. The heat-generating targets serve as radiation sources. The passive distributed radar system receives electromagnetic wave signals from the radiation sources and adopts a four-station three-coordinate positioning principle to achieve continuous three-dimensional spatial displacement monitoring of each target embedded in the tunnel surrounding rock.

[0041] 2. The present invention arranges multiple radiation source advance boreholes on the advance excavation working face, and opens four radar advance boreholes next to the radiation source advance boreholes. Target bodies are pushed and installed in the radiation source advance boreholes, and the target bodies are arranged in an "I" shape. A central station radar, a 1# auxiliary station radar, a 2# auxiliary station radar, and a 3# auxiliary station radar are pushed and installed in the four radar advance boreholes. The central station radar, the 1# auxiliary station radar, the 2# auxiliary station radar, and the 3# auxiliary station radar are arranged in an inverted "Y" shape. The temperature of each target body is controlled by a power supply and temperature control integrated machine, the displacement of each target body is monitored by a radar positioning unit, and the monitoring data is acquired and displayed in real time by a digital display device. This can realize continuous monitoring of the internal displacement of the surrounding rock before and after tunnel excavation;

[0042] 3. The monitoring equipment involved in the present invention, such as the digital display unit and the power supply and temperature control integrated machine, can be recycled and reused, so the overall monitoring cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 Schematic diagram of the arrangement structure of the radiation source advance drilling, radar advance drilling, various target bodies and radar positioning unit in the advance tunnel surrounding rock displacement monitoring system in the first embodiment of the present invention;

[0044] Figure 2 for Figure 1 A top view of

[0045] Figure 3 for Figure 1 Left view of;

[0046] Figure 4 This is a schematic diagram of the connection between a target object in the radiation source unit and the power supply and temperature control integrated machine through an external connection in Example 1;

[0047] Figure 5 This is a schematic diagram of the structure of the central station radar in Example 1;

[0048] Figure 6 Schematic diagram of the structure of the 1# auxiliary station radar, the 2# auxiliary station radar and the 3# auxiliary station radar in Example 1;

[0049] Figure 7 This is a schematic diagram of the connection when the target is pushed and the hole is sealed in the first embodiment of the present invention;

[0050] Figure 8 This is a schematic diagram of the connection of the target body after sealing in Example 1 of the present invention;

[0051] Figure 9 This is a schematic diagram of the connection between the central station mine pushing and hole sealing in the first embodiment of the present invention;

[0052] Figure 10 This is a schematic diagram of the connection of the central station radar after sealing in Example 1 of the present invention;

[0053] Figure 11 This is a schematic diagram of the connection between the radar push and hole sealing of the 1# secondary station in the first embodiment of the present invention;

[0054] Figure 12 This is a schematic diagram of the connection of the radar of the 1# secondary station after sealing in the first embodiment of the present invention;

[0055] Figure 13 This is a principle block diagram of the digital display unit in the first embodiment of the present invention;

[0056] Figure 14 This is a schematic structural diagram of a high-pressure expansion capsule sealing device according to a first embodiment of the present invention;

[0057] Figure 15 This is a structural diagram of a high-pressure expansion capsule sealer connected to a central station radar in Example 1 of the present invention;

[0058] Figure 16 Schematic diagram of the liquid inlet hole of the high-pressure expansion capsule sealing device in Example 1 of the present invention;

[0059] Figure 17 for Figure 14 AA cross-sectional structural diagram;

[0060] Figure 18 This is a flow chart of a method for monitoring displacement of surrounding rock in an advanced roadway according to a second embodiment of the present invention.

[0061] Markings in the figure: 1. Radiation source advance drilling; 2. Radar advance drilling; 3. Target; 31. Metal circular shell; 32. First threaded connection hole; 33. Threading hole; 4. Constant temperature resistor; 5. External connection; 6. Power supply and temperature control integrated unit; 61. Housing; 62. Battery; 63. Temperature controller; 64. Temperature adjustment knob; 65. Switch; 66. External connection hole;

[0062] 7. Central station radar; 71. First shuttle-shaped housing; 72. Central station radar body; 73. Second threaded connection hole;

[0063] 8. 1# auxiliary station radar; 9. 2# auxiliary station radar; 10. 3# auxiliary station radar; 101. Second shuttle-shaped housing; 102. Auxiliary station radar body; 103. Third threaded connection hole;

[0064] 11. Data cable; 12. Data cable plug;

[0065] 13. Digital display unit; 131. External port; 132. Data processing and storage module; 133. Display screen; 134. Data transmission interface; 135. Power supply;

[0066] 14. Solid connecting rod; 15. Polyurethane sealing section; 16. Grouting pipe; 17. Grouting pump; 18. High-pressure expansion capsule sealer; 181. Central pipe; 1811. Inner pipe wall; 1812. Outer pipe wall; 182. Expansion capsule; 183. First connecting pipe; 184. Second connecting pipe; 185. Threaded connection section; 186. Wire hole; 187. Liquid outlet; 188. Liquid inlet.

[0067] 19. Hollow connecting rod; 20. Manual pressure pump; 21. High-pressure injection pipe; 22. Pressure relief device; 23. Cement mortar;

[0068] 100. Tunnel excavation working face; 200. Tunnel right side; 300. Tunnel arched roof; 400. Tunnel floor. DETAILED DESCRIPTION

[0069] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only 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 making creative efforts are within the scope of protection of the present invention.

[0070] Example 1

[0071] Reference Figure 1-Figure 7 , a monitoring system for surrounding rock displacement of an advanced roadway, comprising:

[0072] A plurality of radiation source advance boreholes 1 are opened in the surrounding rock in front of the tunnel excavation working face 100, and four radar advance boreholes 2 are opened next to the plurality of radiation source advance boreholes 1;

[0073] The radiation source unit includes multiple targets 3, multiple constant temperature resistors 4, multiple external wires 5, and a power supply and temperature control integrated device 6. Each radiation source advance borehole 1 is provided with a target 3, and each target 3 is provided with a constant temperature resistor 4. Each constant temperature resistor 4 is connected to the power supply and temperature control integrated device 6 located outside the radiation source advance borehole 1 via an external wire 5. The power supply and temperature control integrated device 6 is used to control the temperature of the constant temperature resistor 4 in each target 3. The target 3 together with the constant temperature resistor 4 is pushed to the bottom of the radiation source advance borehole 1 by the radiation source pushing and mounting unit.

[0074] The radar positioning unit includes a central station radar 7, a No. 1 auxiliary station radar 8, a No. 2 auxiliary station radar 9, and a No. 3 auxiliary station radar 10. The central station radar 7, the No. 1 auxiliary station radar 8, the No. 2 auxiliary station radar 9, and the No. 3 auxiliary station radar 10 are respectively pushed to the bottom of the four radar advance boreholes 2 by a radar pushing and installing unit. The central station radar 7, the No. 1 auxiliary station radar 8, the No. 2 auxiliary station radar 9, and the No. 3 auxiliary station radar 10 constitute a passive distributed radar system. The central station radar 7 is connected to a data cable 11, and a data cable plug 12 is provided at the end of the data cable 11.

[0075] The passive distributed radar system adopts the 4-station (3-coordinate) arrival time difference positioning technology to obtain the position coordinates of each target body 3, wherein the coordinates of the central station are (0, 0, 0), and the coordinates of the 1# auxiliary station radar 8, the 2# auxiliary station radar 9 and the 3# auxiliary station radar 10 are determined according to the actual position. The heated target bodies 3 act as radiation sources to emit electromagnetic wave signals. The 1# auxiliary station radar 8, the 2# auxiliary station radar 9 and the 3# auxiliary station radar 10 receive the electromagnetic wave signals of each target body 3. After preprocessing, the signals are transmitted to the central station radar 7 for data fusion analysis. By calculating the time difference between the 1# auxiliary station radar 8, the 2# auxiliary station radar 9 and the 3# auxiliary station radar 10 and the central station radar 7 in receiving the signals of each target body 3, the position coordinates of each target body 3 can be obtained, and the target body 3 is positioned;

[0076] Reference Figure 13 The digital display unit 13 includes an external port 131, a data processing and storage module 132, a display screen 133, a data transmission interface 134, and a power supply 135. The data cable plug 12 is connected to the external port 131. The data processing and storage module 132 is used to calculate and process data transmitted by the central station radar 7 and store the processed data. The display screen 133 is used to display data information. The data transmission interface 134 is used to connect to an external device and transmit the stored data to the external device. The power supply 135 is used to power the data processing and storage module 132 and the display screen 133. The external device can be a laptop computer, a mobile phone, etc.

[0077] The data transmission interface 134 is a USB interface.

[0078] Reference Figure 4 The target body 3 includes a metal circular shell 31, which has a hollow structure inside. A first threaded connection hole 32 is opened on the metal circular shell 31, and a wire hole 33 is opened next to the first threaded connection hole 32. The constant temperature resistor 4 is fixed inside the metal circular shell 31, and the external wire 5 on the constant temperature resistor 4 passes through the wire hole 33.

[0079] The integrated power supply and temperature control device 6 includes a housing 61, a battery 62, a temperature controller 63, a temperature adjustment knob 64, and a switch 65. The housing 61 houses the battery 62 and the temperature controller 63. The housing 61 is provided with the temperature adjustment knob 64 and the switch 65. The temperature adjustment knob 64 is connected to the temperature controller 63. The housing 61 also includes a plurality of external connection holes 66. The external wires 5 on the thermostat resistors 4 in each target body 3 are connected to the battery 62 through the external connection holes 66. The battery 62 and the temperature controller 63 are separately connected. The temperature adjustment knob 64 is connected to the temperature controller 63, and the switch 65 is connected to the battery 62. The battery 62 is an intrinsically safe battery for mining use. The temperature adjustment knob 64 has temperature settings of 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, and 90°C. Rotating the temperature adjustment knob 64 controls the temperature controller 63 to heat the thermostat resistors 4 to the temperature values ​​of the aforementioned settings.

[0080] Reference Figure 5 The central station radar 7 includes a first shuttle-shaped housing 71, in which a central station radar body 72 is fixed. A second threaded connection hole 73 is provided at the end of the first shuttle-shaped housing 71. The central station radar body 72 is connected to the data cable 11, and the data cable 11 passes through the second threaded connection hole 73.

[0081] Reference Figure 6 The first, second, and third auxiliary radars 8, 9, and 10 all have the same structure, each including a second shuttle-shaped housing 101, within which a secondary radar body 102 is secured. A third threaded hole 103 is defined at the distal end of the second shuttle-shaped housing 101. The second and third threaded holes 73, 103 are used to connect to the high-pressure expansion capsule sealer 18.

[0082] The first shuttle-shaped housing 71 and the second shuttle-shaped housing 101 have the same appearance, both of which are shuttle-shaped structures, which facilitate their movement in the drilled hole, and are made of wear-resistant and flame-retardant materials.

[0083] Reference Figure 7-Figure 8 The radiation source pushing installation unit includes multiple solid connecting rods 14, a polyurethane sealing part 15, a grouting pipe 16 and a grouting pump 17. After the multiple solid connecting rods 14 are threadedly connected in sequence, the first solid connecting rod 14 is connected to the target body 3, and the target body 3 is pushed to the bottom of the radiation source advance drilling hole 1. The polyurethane sealing part 15 is formed at the mouth of the radiation source advance drilling hole 1 by polyurethane sealing. The front end of the grouting pipe 16 passes through the polyurethane sealing part 15 and is placed inside the radiation source advance drilling hole 1. The end of the grouting pipe 16 is connected to the grouting pump 17, and the cement mortar 23 is injected into the radiation source advance drilling hole 1 through the grouting pipe 16 by the grouting pump 17.

[0084] Reference Figures 9-12The radar pushing and installation unit includes a high-pressure expansion capsule sealer 18, multiple hollow connecting rods 19, a manual pressure pump 20, a high-pressure liquid injection pipe 21 and a pressure relief device 22. The multiple hollow connecting rods 19 are connected in sequence by threads. The front end of the high-pressure expansion capsule sealer 18 is threadedly connected to the central station radar 7, 1# auxiliary station radar 8, 2# auxiliary station radar 9 or 3# auxiliary station radar 10, and the end of the high-pressure expansion capsule sealer 18 is threadedly connected to the first hollow connecting rod 19. The end of the high-pressure expansion capsule sealer 18 is also connected to one end of the high-pressure liquid injection pipe 21, and the other end of the high-pressure liquid injection pipe 21 is connected to the pressure relief device 22, and the pressure relief device 22 is connected to the manual pressure pump 20.

[0085] Both the solid connecting rod 14 and the hollow connecting rod 19 are 1.0m long and 20mm-30mm in diameter, made of a strong plastic material. During deployment, the number of solid connecting rods 14 and hollow connecting rods 19 is selected based on the depth of the radiation source advance borehole 1 and the radar advance borehole 2.

[0086] Reference Figure 14-17 The high-pressure expansion capsule sealer 18 includes a central tube 181 and an expansion capsule 182. The central tube 181 is a cylindrical tube body with closed ends and a cavity inside. The tube wall of the central tube 181 is a double-layer structure, including an inner tube wall 1811 and an outer tube wall 1812. There is a hollow structure between the inner tube wall 1811 and the outer tube wall 1812, and a plurality of liquid outlet holes 187 are opened axially on the outer tube wall 1812. The expansion capsule 182 is wrapped on the outer peripheral surface of the outer tube wall 1812. A first connecting tube 183 and a second connecting tube 184 are respectively axially provided at the center of the left end face and the right end face of the central tube 181. The interiors of the first connecting tube 183 and the second connecting tube 184 are both hollow structures. At the corresponding position of the second connecting tube 184, through holes are respectively provided on the left end face and the right end face of the central tube 181. The first connecting tube 183 and the second connecting tube 184 are connected to the internal cavity of the central tube 181 through the through holes. Threaded connecting sections 185 are respectively provided on the first connecting tube 183 and the second connecting tube 184. A liquid inlet hole 188 is provided on the right end face of the central tube 181 between the inner tube wall 1811 and the outer tube wall 1812. The liquid in the high-pressure liquid injection tube 21 flows into the space between the inner tube wall 1811 and the outer tube wall 1812 through the liquid inlet hole 188, and flows out through multiple liquid outlet holes 187, so that the expansion capsule 182 expands to seal the radar advance drilling hole 2.

[0087] Unlike the high-pressure expansion capsule sealer 18 that fixes the 1# auxiliary station radar 8, 2# auxiliary station radar 9 or 3# auxiliary station radar 10, in the high-pressure expansion capsule sealer 18 that fixes the central station radar body 72, a wire hole 186 is also provided on the second connecting tube 184. The data cable 11 and the data cable plug 12 connected to the central station radar body 72 pass through the first connecting tube 183 and the internal cavity of the central tube 181 in turn, and finally pass through the wire hole 186 on the second connecting tube 184. After passing through the radar advance drilling 2, the data cable plug 12 is connected to the digital display unit 13.

[0088] The overall length of the high-pressure expansion capsule sealer 18 is 30cm-50cm, and its function is to fix the central station radar 7, 1# auxiliary station radar 8, 2# auxiliary station radar 9 and 3# auxiliary station radar 10 to prevent them from moving in the radar advance borehole 2.

[0089] Example 2

[0090] Reference Figures 1-18 A method for monitoring displacement of surrounding rock in an advanced roadway is implemented using the system for monitoring displacement of surrounding rock in an advanced roadway described in Example 1, and specifically comprises the following steps:

[0091] S1. Monitoring plan design: Based on the current status of the tunnel excavation working face 100, design the number of targets 3 in the radiation source unit, the layout of each target 3, and the layout of the central station radar 7, 1# auxiliary station radar 8, 2# auxiliary station radar 9, and 3# auxiliary station radar 10 in the radar positioning unit. The targets 3 can be arranged in the right side, left side, roof, and floor rock layers of the tunnel as needed, while the central station radar 7, 1# auxiliary station radar 8, 2# auxiliary station radar 9, and 3# auxiliary station radar 10 of the radar positioning unit should be arranged in the surrounding rock on the right or left side of the tunnel.

[0092] In this embodiment, the number of target bodies 3 of the radiation source unit is 9, which are arranged in the surrounding rock on the right side of the tunnel and the surrounding rock on the roof to monitor the displacement of the surrounding rock on the right side of the tunnel and the surrounding rock on the roof. The specific arrangement positions are:

[0093] Five targets 3 are arranged in a straight line on the right side of the tunnel excavation working face 100 at a distance of L9, with L9 = 5m-8m. The spacing between the targets 3 is L2, with L2 = 0.5m-1.0m. The height of each target 3 from the tunnel floor 400 is L8, with L8 = 0.5m-2.0m. The first target 3 is located on the right side of the tunnel right wall 200, and its distance from the right tunnel wall 200 is L1, with L1 = 0.5m-2.0m.

[0094] At the same time, at a distance L9 from the front of the tunnel excavation working face 100, four target bodies 3 are arranged vertically upward along the center position of the tunnel excavation working face 100, and the distance between each target body 3 is L4, L4 = 1.0m-2.0m;

[0095] The first target body 3 located above the tunnel arched roof 300 has a distance L3 from the highest point of the tunnel arched roof 300, where L3 = 0.5 m - 2.0 m.

[0096] The central station radar 7, 1# auxiliary station radar 8, 2# auxiliary station radar 9 and 3# auxiliary station radar 10 in the radar positioning unit are arranged in an inverted "Y" shape on the right side of the five target bodies 3. The height of the 1# auxiliary station radar 8 and the 2# auxiliary station radar 9 are equal, and the height of 400 from the tunnel bottom is equal to the height L8 of the five target bodies 3. The distance between the 1# auxiliary station radar 8 and the 2# auxiliary station radar 9 is L 12 , L 12 =2.0m-5.0m, the central station radar 7 and the 3# auxiliary station radar 10 are successively located above the center of the connection line of the 1# auxiliary station radar 8 and the 2# auxiliary station radar 9, the distance between the central station radar 7 and the connection lines of the 1# auxiliary station radar 8 and the 2# auxiliary station radar 9 is L6, L6=1.0m-5.0m, the distance between the 3# auxiliary station radar 10 and the central station radar 7 is L7, L7=0.5m-4.0m, the extension line of the connection line of the five target bodies 3 intersects with the center of the connection line of the 1# auxiliary station radar 8 and the 2# auxiliary station radar 9 and is perpendicular to it; the distance between the connection line of the 1# auxiliary station radar 8 and the 2# auxiliary station radar 9 and the last target body 3 located on the right side of the right side 200 of the lane is L5, L5=2m-3m.

[0097] S2, advance drilling construction: radiation source advance drilling 1 and radar advance drilling 2 are constructed. According to the above-mentioned design parameters, a drilling rig is used to construct radiation source advance drilling 1 and radar advance drilling 2 on the side of the tunnel along the tunnel excavation working face 100 in the excavation direction. The diameter of the drilling holes is 75 mm. The drilling depth is determined according to the specific layout of the designed target body 3 and the central station radar 7, the 1# auxiliary station radar 8, the 2# auxiliary station radar 9 and the 3# auxiliary station radar 10. During the drilling process, cores are taken from different rock layers and processed into rock samples. At the same time, in order to prevent deviation during the drilling construction, anti-deviation measures should be taken (such as installing a drilling measuring instrument);

[0098] The radiation source of the five target bodies 3 placed in the surrounding rock on the right side of the tunnel is placed in the same position as the leading drilling hole 1, and is located 100L away from the tunnel excavation working face. 10 The rear tunnel right side 200; in the tunnel arched roof 300 surrounding rock arranged in the four target bodies 3 release the radiation source advance drilling 1 opening position is the same, and is located at a distance from the tunnel excavation working face 100L 10 At the center of the rear roadway arched roof 300, L10 =5m-8m;

[0099] The radar advance drilling 2 opening position of the central station radar 7, 1# auxiliary station radar 8, 2# auxiliary station radar 9 and 3# auxiliary station radar 10 is located on the right side of the tunnel 200 and is located L behind the opening position of the radiation source advance drilling 1 of the surrounding rock 5 target body 3 on the right side of the tunnel. 11 Within the range, L 11 =1.0m-3.0m;

[0100] S3, laboratory experiment: The processed rock samples were placed in a laboratory constant temperature box to maintain the same temperature as the surrounding rock temperature of the on-site tunnel. Then, a target body 3 with a constant temperature resistor 4 inside was placed in rock samples of different rock formations. The temperature of the constant temperature resistor 4 was controlled by a power supply and temperature control integrated device 6. The propagation speed and attenuation rate of thermal radiation (electromagnetic waves) generated by the target body 3 in the rock samples of different rock formations under different temperature conditions were measured. The temperatures were set to 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, and 90°C respectively.

[0101] Conduct 3-5 measurements on the rock sample of each rock layer, and compare and analyze the measurement results to determine the temperature value of the thermal radiation generated by the target body 3 at the optimal propagation speed and attenuation rate;

[0102] S4, installation of each target body and radar positioning unit:

[0103] Each target body 3 is pushed to the bottom of the radiation source advance drilling hole 1 by the radiation source pushing installation unit, and a polyurethane sealing portion 15 is formed at the opening of each radiation source advance drilling hole 1 by polyurethane sealing, and the front end of the grouting pipe 16 is passed through the polyurethane sealing portion 15 and placed inside the radiation source advance drilling hole 1, and the end of the grouting pipe 16 is connected to the grouting pump 17, and the cement mortar 23 is injected into the radiation source advance drilling hole 1 through the grouting pipe 16 by the grouting pump 17;

[0104] The central station radar 7, the 1# auxiliary station radar 8, the 2# auxiliary station radar 9, and the 3# auxiliary station radar 10 are respectively pushed to the bottom of the radar advance borehole 2 by the radar pushing and installing unit, and the manual pressure pump 20 is turned on to input high-pressure liquid into the high-pressure expansion capsule sealer 18 to expand the expansion capsule 182 to seal the hole;

[0105] S5, system trial operation: connect the external wire 5 of each target body 3 to the power supply and temperature control integrated machine 6, and control the constant temperature resistor 4 in each target body 3 to heat to the temperature value determined in step S3 through the power supply and temperature control integrated machine 6;

[0106] Connect the central station radar 7 to the data cable 11, and connect the data cable plug 12 at the end of the data cable 11 to the external port 131 of the digital display unit 13 to monitor and check the position of each target body 3, and compare and analyze it with the layout position designed in step S1 to check the error range. The error range must not exceed 5mm. If the layout position exceeds the error range, correct the positioning system to make it within the allowable error range.

[0107] S6, surrounding rock displacement monitoring: As the tunnel continues to advance, the target bodies 3 inside the tunnel surrounding rock will move in response to changes in the tunnel surrounding rock. These targets will be monitored by the 1# auxiliary station radar 8, the 2# auxiliary station radar 9, and the 3# auxiliary station radar 10, and the displacement data will be obtained and stored in the digital display unit 13;

[0108] According to actual needs on site, when the tunnel excavation working face 100 exceeds each target body 3 and when the displacement data of each target body 3 no longer changes, the monitoring can be ended;

[0109] S7, device recovery:

[0110] After the monitoring is completed, the digital display unit 13 is first removed and preserved so that it can be brought to the ground and its internal data is connected to the external device through the data transmission interface 134, and the data is imported into the external device (laptop computer, mobile phone) for analysis; then each radar push installation unit is depressurized and the central station radar 7, 1# sub-station radar 8, 2# sub-station radar 9 and 3# sub-station radar 10 are gradually taken out, and the radar advance drilling 2 is sealed after being taken out; at the same time, the power supply and temperature control integrated machine 6 is recycled for next use.

[0111] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A system for monitoring displacement of surrounding rock in advanced roadway, characterized in that: include: Multiple radiation source advance drill holes are drilled in the surrounding rock in front of the tunnel excavation working face, and four radar advance drill holes are drilled next to the multiple radiation source advance drill holes. The radiation source unit includes multiple targets, multiple constant temperature resistors, multiple external wirings, and a power supply and temperature control integrated device. Each target is provided in each radiation source advance borehole. Each target is provided with a constant temperature resistor. Each constant temperature resistor is connected to the power supply and temperature control integrated device located outside the radiation source advance borehole via an external wiring. The power supply and temperature control integrated device is used to control the temperature of the constant temperature resistor in each target. The target and the constant temperature resistor are pushed to the bottom of the radiation source advance borehole via the radiation source pushing and mounting unit. Radar positioning unit, including central station radar, 1# auxiliary station radar, 2# auxiliary station radar and 3# auxiliary station radar; The central station radar, auxiliary station radar #1, auxiliary station radar #2, and auxiliary station radar #3 are respectively pushed to the bottom of the four radar advance boreholes via radar push installation units. The auxiliary station radars #1, #2, and #3 monitor the displacement of multiple targets in real time and transmit the data to the central station radar. The central station radar is connected to a data cable, and a data cable plug is provided at the end of the data cable; The digital display unit includes an external port, a data processing and storage module, a display screen, a data transmission interface and a power supply. The data cable plug is connected to the external port. The data processing and storage module is used to calculate and process the data transmitted by the central station radar and store the processed data; the display screen is used to display data information; the data transmission interface is used to connect to an external device and transmit the stored data to the external device; the power supply is used to power the data processing and storage module and the display screen.

2. The system for monitoring displacement of surrounding rock in an advanced roadway according to claim 1, characterized in that: The target body includes a metal circular shell with a hollow structure inside. A first threaded connection hole is opened on the metal circular shell, and a wire threading hole is opened next to the first threaded connection hole. The constant temperature resistor is fixed inside the metal circular shell, and the external wire on the constant temperature resistor passes through the wire threading hole.

3. The system for monitoring displacement of surrounding rock in an advanced roadway according to claim 1, characterized in that: The power supply and temperature control integrated machine includes a shell, a battery, a temperature controller, a temperature adjustment knob and a switch. The battery and the temperature controller are arranged inside the shell, and the temperature adjustment knob and the switch are arranged on the shell. The temperature adjustment knob is connected to the temperature controller. The shell is also provided with multiple external connection holes. The external wires on the constant temperature resistor in each target body are respectively connected to the battery through the external connection holes. The battery and the temperature controller are also connected separately, the temperature adjustment knob is connected to the temperature controller, and the switch is connected to the power supply.

4. The system for monitoring displacement of surrounding rock in an advanced roadway according to claim 1, wherein: The central station radar includes a first shuttle-shaped shell, in which the central station radar body is fixed, and a second threaded connection hole is opened at the end of the first shuttle-shaped shell. The central station radar body is connected to the data line, and the data line passes through the second threaded connection hole; The 1# auxiliary station radar, 2# auxiliary station radar and 3# auxiliary station radar have the same structure and all include a second shuttle-shaped shell, in which the auxiliary station radar body is fixed, and a third threaded connection hole is opened at the end of the second shuttle-shaped shell.

5. The system for monitoring displacement of surrounding rock in an advanced roadway according to claim 1, wherein: The radiation source pushing installation unit includes multiple solid connecting rods, a polyurethane sealing part, a grouting pipe and a grouting pump. After the multiple solid connecting rods are threadedly connected in sequence, the first solid connecting rod is connected to the target body, and the target body is pushed to the bottom of the radiation source advance drilling hole. The polyurethane sealing part is formed at the mouth of the radiation source advance drilling hole by polyurethane sealing. The front end of the grouting pipe passes through the polyurethane sealing part and is placed inside the radiation source advance drilling hole. The end of the grouting pipe is connected to the grouting pump, and the cement mortar is injected into the radiation source advance drilling hole through the grouting pipe by the grouting pump.

6. The system for monitoring displacement of surrounding rock in an advanced roadway according to claim 1, characterized in that: The radar pushing and installation unit includes a high-pressure expansion capsule sealer, multiple hollow connecting rods, a manual pressure pump, a high-pressure liquid injection pipe and a pressure relief device. The multiple hollow connecting rods are connected in sequence through threads. The front end of the high-pressure expansion capsule sealer is connected to the central station radar, 1# auxiliary station radar, 2# auxiliary station radar or 3# auxiliary station radar through threads. The end of the high-pressure expansion capsule sealer is connected to the first hollow connecting rod through threads. The end of the high-pressure expansion capsule sealer is also connected to one end of the high-pressure liquid injection pipe. The other end of the high-pressure liquid injection pipe is connected to the pressure relief device, and the pressure relief device is connected to the manual pressure pump.

7. The system for monitoring displacement of surrounding rock in an advanced roadway according to claim 6, characterized in that: The cam is connected to the outer cover of the tank by a hole, and the cam is connected to the cover by a hole, and the cam is connected to the cover by a hole.

8. The system for monitoring displacement of surrounding rock in an advanced roadway according to claim 7, characterized in that: A wire hole is also provided on the second connecting tube. The data cable and data cable plug connected to the central station radar body pass through the first connecting tube, the internal cavity of the central tube, and the second connecting tube in sequence, and finally pass through the wire hole and pass through the radar advance drilling. The data cable plug is connected to the digital display unit.

9. A method for monitoring displacement of surrounding rock in an advanced roadway, implemented by using the system for monitoring displacement of surrounding rock in an advanced roadway according to any one of claims 1 to 8, characterized in that: The specific steps include: S1, monitoring scheme design: according to the current status of the tunnel excavation working face, design the number of targets in the radiation source unit, the layout of each target, and the layout of the central station radar, 1# auxiliary station radar, 2# auxiliary station radar and 3# auxiliary station radar in the radar positioning unit; S2, advance drilling construction: Radiation source advance drilling and radar advance drilling construction. According to the above-mentioned design parameters, a drilling rig is used to construct radiation source advance drilling and radar advance drilling on the roadway wall along the excavation direction of the roadway excavation working face. The drilling depth is determined by the specific layout of the designed target object and radar positioning unit. During the drilling process, different rock layers are cored and processed into rock samples; S3, laboratory experiment: The processed rock samples were placed in a laboratory constant temperature chamber to maintain the same temperature as the surrounding rock of the on-site tunnel. A target body equipped with a constant temperature resistor was then placed in rock samples from different rock formations. The temperature of the constant temperature resistor was controlled by a power supply and temperature controller. The propagation speed and attenuation rate of thermal radiation generated by the target body in the rock samples from different rock formations under different temperature conditions were measured. The temperatures were set at 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, and 90°C. Conduct 3-5 measurements on rock samples of each rock layer, and compare and analyze the measurement results to determine the temperature value of the thermal radiation generated by the target body at the optimal propagation speed and attenuation rate; S4, radiation source unit and radar positioning unit installation: Each target object is pushed to the bottom of the radiation source advance drilled hole by the radiation source pushing installation unit, and a polyurethane sealing portion is formed at the opening of each radiation source advance drilled hole by polyurethane sealing, and the front end of the grouting pipe is passed through the polyurethane sealing portion and placed inside the radiation source advance drilled hole, and the end of the grouting pipe is connected to the grouting pump, and the cement mortar is injected into the radiation source advance drilled hole through the grouting pipe by the grouting pump; Push the central station radar, No. 1 auxiliary station radar, No. 2 auxiliary station radar, and No. 3 auxiliary station radar to the bottom of the radar advance borehole through the radar pushing and installation unit, and start the manual pressure pump to input high-pressure liquid into the expansion capsule sealer to expand the expansion capsule to seal the hole; S5, system trial operation: connect the external wiring of each target body to the power supply and temperature control integrated machine, and adjust the temperature value of the constant temperature resistor according to the actual surrounding rock temperature on site through the power supply and temperature control integrated machine according to the surrounding rock temperature outside each target body; Connect the central station radar to the data cable, and connect the data cable plug at the end of the data cable to the external port of the digital display unit to monitor and view the position of each target; S6, surrounding rock displacement monitoring: As the tunnel continues to advance, the target objects inside the tunnel surrounding rock will move with the changes in the tunnel surrounding rock. The displacement data will be monitored by the 1#, 2# and 3# auxiliary station radars and stored in the digital display unit. According to the actual needs on site, when the tunnel excavation working face exceeds each target body and when the displacement data of each target body no longer changes, the monitoring can be ended; S7, device recovery: After the monitoring is completed, the digital display unit is first removed and preserved so that it can be brought to the ground and its internal data is connected to the external device through the data transmission interface, and the data is imported into the external device for analysis; then each radar push installation unit is depressurized and the central station radar, 1# auxiliary station radar, 2# auxiliary station radar and 3# auxiliary station radar are gradually taken out, and the radar advance drilling holes are sealed after taking them out; at the same time, the power supply and temperature control integrated machine is recycled for next use.

10. The method for monitoring displacement of surrounding rock in an advanced roadway according to claim 9, characterized in that: In step S1, the number of target bodies of the radiation source unit is 9, which are arranged in the surrounding rock on the right side of the roadway and the surrounding rock on the roof to monitor the displacement of the surrounding rock on the right side of the roadway and the surrounding rock on the roof. The specific arrangement positions are: There are five targets arranged in a straight line on the right side of L9 in front of the tunnel working face, with L9 = 5m-8m. The spacing between each target is L2, with L2 = 0.5m-1.0m. The height of each target from the tunnel floor is L8, with L8 = 0.5m-2.0m. The first target on the right side of the tunnel right side has a distance of L1 from the right side of the tunnel, with L1 = 0.5m-2.0m. At the same time, at a distance of L9 in front of the tunnel excavation working face, four target bodies are arranged vertically upward along the center of the tunnel excavation working face, and the spacing between each target body is L4, L4 = 1.0m-2.0m. The first target body located above the arched roof of the tunnel has a distance L3 from the highest point of the arched roof of the tunnel, where L3 = 0.5m-2.0m; The central station radar, 1# auxiliary station radar, 2# auxiliary station radar and 3# auxiliary station radar in the radar positioning unit are arranged in an inverted "Y" shape on the right side of the five targets. The heights of 1# auxiliary station radar and 2# auxiliary station radar are equal, and the height from the roadway floor is equal to the height L8 of the five targets. The distance between 1# auxiliary station radar and 2# auxiliary station radar is L 12 , L 12 = 2.0m-5.0m, the central station radar and the 3# auxiliary station radar are located above the center of the line connecting the 1# auxiliary station radar and the 2# auxiliary station radar, respectively. The distance between the central station radar and the 1# auxiliary station radar and the 2# auxiliary station radar is L6, L6 = 1.0m-5.0m, the distance between the 3# auxiliary station radar and the central station radar is L7, L7 = 0.5m-4.0m, the extended line connecting the five targets intersects and is perpendicular to the center of the line connecting the 1# auxiliary station radar and the 2# auxiliary station radar; the distance between the line connecting the 1# auxiliary station radar and the 2# auxiliary station radar and the last target located on the right side of the right side of the tunnel is L5, L5 = 2m-3m; In step S2, the radiation sources of the five target bodies arranged in the surrounding rock on the right side of the tunnel are placed in the same position for the advanced drilling holes, and are located at a distance of L from the tunnel excavation working face. 10 On the right side of the rear tunnel; the radiation source of the four target bodies arranged in the tunnel arch roof surrounding rock has the same position of the advanced drilling hole, and is located at a distance of L from the tunnel excavation working face. 10 At the center of the arched roof of the rear tunnel, L 10 =5m-8m; The radar advance drilling opening positions of the central station radar, 1# auxiliary station radar, 2# auxiliary station radar and 3# auxiliary station radar are located on the right side of the tunnel and L behind the radiation source advance drilling opening positions of the five target bodies in the surrounding rock on the right side of the tunnel. 11 Within the range, L 11 =1.0m-3.0m.

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