Intelligent monitoring method for subsidence of ground around site in subway shield construction

Abstract

The invention discloses an intelligent monitoring method for subsidence of the ground around a site in subway shield construction, and relates to the technical field of shield construction subsidence monitoring. 2, determining an installation scheme of the intelligent monitoring equipment; 3, positioning and installing the intelligent monitoring equipment; 4, liquid injection operation is conducted on the intelligent detection equipment; step 5, installing a corresponding data relay; 6, executing a data verification program; 7, analyzing and judging the monitoring data; and 8, classifying and archiving the monitoring data. According to the intelligent monitoring method for subsidence of the ground around the site in subway shield construction, intelligent equipment is adopted for monitoring according to the type of a house building, the monitoring efficiency and the monitoring precision are improved, and it can be guaranteed that monitoring is conducted for 24 h; the overall working efficiency is improved, and the construction cost is saved.

Description

Technical Field

[0001] The invention relates to the technical field of shield construction settlement monitoring, and in particular to an intelligent monitoring method for ground settlement around a site during subway shield construction. Background Art

[0002] Subway shield construction is an advanced technology that uses a shield machine to dig tunnels. First, at the shield starting shaft, the shield machine is assembled and positioned on the predetermined axis. During the construction process, the shield machine cuts the soil through the rotation of the cutter head. At the same time, the soil pressure and water pressure of the face are balanced by the front soil pressure or mud water pressure to maintain the stability of the excavation face. The cut soil is transported out of the tunnel by a belt conveyor. When the shield machine advances, concrete or mortar is injected synchronously to form the tunnel lining. The shield machine is equipped with a precise measurement and control system to ensure that the tunnel is accurately advanced along the designed axis. During the construction process, it is also necessary to pay close attention to factors such as surface settlement, shield machine posture, and lining quality to ensure construction safety. Shield construction has the advantages of small impact on the ground, fast construction speed, safety and efficiency, and is suitable for underground engineering construction such as subways and urban underground pipe galleries.

[0003] However, during the construction process of subway shield construction, certain stratum disturbances and groundwater level drops will occur, and these factors will cause the ground and surrounding soil to settle, affecting the safety of surface buildings and underground facilities, which can easily have an adverse impact on the daily lives of surrounding residents. In order to ensure the long-term and stable development of the subway industry, it is necessary to adopt efficient monitoring methods for the ground settlement problems that occur during the construction process. Summary of the invention

[0004] In view of the deficiencies of the prior art, the present invention provides an intelligent monitoring method for ground settlement around a site during subway shield construction, which solves the problems raised in the above-mentioned background technology.

[0005] To achieve the above objectives, the present invention is implemented by the following technical solutions: an intelligent monitoring method for ground subsidence around a site during subway shield construction, comprising the following specific steps:

[0006] Step 1: Construction preparation and selection of appropriate intelligent monitoring equipment;

[0007] Step 2: Determine the installation plan of the intelligent monitoring equipment. The intelligent monitoring equipment specifically uses a static level, specifically a magnetic static level;

[0008] Step 3: Position and install the intelligent monitoring equipment. The specific steps are as follows:

[0009] S1. Use a laser level to determine the horizontal line on the installation surface according to the selected points, and determine the points and installation lines on the horizontal line at the same time;

[0010] S2. Use an impact drill to drill holes at the determined points, fix the bolts inside the holes, and fix the mounting plate with the bolts. The mounting plate must be aligned with the mounting line.

[0011] S3. Three nuts are installed in parallel on the fixed mounting plate. The nut in the middle is used for positioning the fixed mounting plate, and the other two nuts are used to adjust the horizontal height of the level by thread matching;

[0012] S4. After installing the level according to the above steps according to the measuring point, replace the vent screw on the side of the level with the liquid plug screw and tighten it;

[0013] S5. Connect all the level gauges using liquid pipes through the liquid pipe interface;

[0014] Step 4: Perform the liquid injection operation into the intelligent detection equipment. After the level gauge is installed, the short pipe needs to be injected with liquid. The length of the short pipe is less than 100m. The specific steps are as follows:

[0015] S1. Before filling the liquid, use a flat-blade screwdriver to loosen the plug screws on all the level gauges;

[0016] S2. Put the water pump into the bucket filled with antifreeze, connect the water pump to the left liquid pipe of the level gauge at the first measuring point, and put the right liquid pipe of the level gauge at the last measuring point into another empty container;

[0017] S3. After the scale of the first measuring point reaches 50-60, tighten the plug screw on the top of the device. The other static levels are filled with liquid in sequence according to the above steps until all the static levels are filled with liquid.

[0018] S4. When the liquid is pumped to the last measuring point, you need to first remove the right liquid tube and replace it with the short liquid tube placed here before pumping and plug it with a plug. When the scale of the level at the last measuring point reaches 50-60, tighten the upper plug screw;

[0019] S5. Unplug the long liquid tube connecting the water pump to the level gauge, then loosen the upper plug screw, wait for the antifreeze to flow out from the left side of the level gauge, use the short liquid tube to connect the left side of the upper measuring point, until the antifreeze fills the short liquid tube and then plugs the plug, and finally tighten the upper plug screw;

[0020] S6. After filling the level, remember to replace the filling plugs on the side of all measuring point level gauges with the original air vent screws;

[0021] Step 5: Install the corresponding data transfer devices, the number of which is set to one fifth of the static level, and one data transfer device is equipped for every five static levels;

[0022] Step 6: Execute data verification procedures. Data testing includes but is not limited to setting the frequency of data collection, real-time monitoring of data transmission and reception, and verification of data accuracy and reliability;

[0023] Step 7: Analyze and judge the monitoring data, automatically identify and filter out the data records with problems, calculate the collected data, take the original value of the offset angle of each point, collect multiple times at different frequencies, and compare and analyze with the original value and the previous value to determine whether the settlement of the point meets the requirements;

[0024] Step 8: The monitoring data is classified and archived. After a short-term data analysis, the data is stored in the database platform backend in an orderly manner in the form of a time series. The data is exported from the database platform for local storage. The house settlement data is automatically processed and predicted using time series analysis and regression analysis methods.

[0025] Optionally, the construction preparation in step 1 is specifically as follows:

[0026] According to the location where the shield tunnel passes through, the affected buildings are determined, and the degree of impact on the buildings is graded and classified. The specific classification is as follows:

[0027] Level 1 risk: buildings located directly above the tunnel shield construction route;

[0028] Level 2 risk: surface and underground buildings within 8-12m on both sides of the tunnel shield construction centerline;

[0029] Level 3 risk: surface and underground buildings 16-24m on both sides of the tunnel centerline.

[0030] Optionally, the installation scheme of the intelligent monitoring device in step 2 is as follows:

[0031] The installation plan includes installation route planning, installation location determination, and installation quantity determination;

[0032] Installation route planning is used to ensure that the installation positions of intelligent monitoring equipment are on the same horizontal line;

[0033] The installation location is determined, including columns, shear walls, and foundation structures;

[0034] The installation quantity and the distance between adjacent intelligent monitoring devices are in the range of 5-10m.

[0035] Optionally, the static level in step 2 is composed of a measuring rod, an electronic compartment, and a non-contact magnetic floating ball sleeved on the measuring rod, wherein a magnetostrictive wire is installed in the measuring rod, and the measuring rod is made of a non-magnetic stainless steel tube;

[0036] The static level gauge generates a starting pulse by the circuit. When the starting pulse is transmitted in the waveguide wire, a rotating magnetic field is generated along the direction of the waveguide wire. When the magnetic field meets the magnetic field in the float, a magnetostrictive effect is generated, causing the waveguide wire to twist. This twisting is sensed by the electronic energy pickup mechanism and converted into a corresponding current pulse. The measuring circuit calculates the time difference between the two pulses, that is, the measured liquid level value.

[0037] Optionally, the data transfer device in step five adopts a six-channel and multi-channel data acquisition instrument, realizes data collection, management, and transmission through PC-side software and database platform, and performs real-time collection, timed collection, data drawing, data warning, and data export on the connected sensors.

[0038] Optionally, the data transfer device includes a sensor, a signal conditioner, an analog-to-digital converter, a data storage device, and a communication interface;

[0039] The basic principles are as follows:

[0040] Sensor: It senses the change of physical quantity and converts it into electrical signal;

[0041] Signal conditioner: amplifies, filters, linearizes, and processes the electrical signals output by the sensor to ensure signal stability and accuracy;

[0042] Analog-to-digital converter: converts analog signals into digital signals for digital processing and storage;

[0043] Data storage: used to store collected data, including RAM, ROM, and FLASH;

[0044] Communication interface: used to transfer the collected data to a computer or other device, including serial port, Ethernet, and USB.

[0045] The present invention provides an intelligent monitoring method for ground settlement around a site during subway shield construction, which has the following beneficial effects:

[0046] This intelligent monitoring method for ground settlement around the site during subway shield construction includes scheme setting, equipment installation, equipment debugging, data analysis, etc. It uses intelligent equipment for monitoring to improve monitoring efficiency and accuracy, and can ensure 24-hour monitoring; it improves overall work efficiency and saves construction costs;

[0047] This method uses a magnetostrictive static level, a new generation of high-precision liquid level measurement products developed using the magnetostrictive principle. It is a non-contact liquid level measurement sensor. The measurement principle is to measure the distance from the internal emission part of the electronic warehouse to the float ball, and calculate the level change of the liquid surface where the float ball is located. It is mainly used for vertical displacement monitoring and has the characteristics of high resolution, high precision, high stability, high reliability, fast response time, and long working life.

[0048] The data transfer device in the present invention adopts solar charging mode, and can be charged by absorbing sunlight energy through solar panels, thereby achieving energy self-sufficiency; this environmentally friendly and sustainable energy solution not only reduces operating costs, but also reduces environmental pollution;

[0049] Executing the data verification procedure can set the specific frequency of data collection of the intelligent monitoring system in detail, and ensure the accuracy and stability of the intelligent monitoring equipment during the data transmission process, as well as the correctness and reliability of the data receiving database platform when receiving the data; before officially starting the data collection work, a series of data tests are carried out, including but not limited to the setting of data collection frequency, real-time monitoring of data sending and receiving, and verification of data accuracy and reliability, to ensure that the entire data monitoring system is in good operating condition and can accurately complete the data collection, processing and analysis tasks; through data testing, any problems that may exist in the system can be discovered and solved in a timely manner, thereby ensuring the smooth progress of the formal data collection process and the accuracy and effectiveness of subsequent data analysis;

[0050] The over-limit standards during the use of reagents in this method can be manually set according to the building codes and standards of different regions to ensure that our analysis results can meet the specific needs of different regions; such flexibility enables our data analysis work to more accurately serve the housing safety monitoring work in various places. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 It is a schematic diagram of the process in the invention;

[0052] Figure 2 It is a schematic diagram of the structure of the static level in the invention;

[0053] Figure 3 This is a schematic diagram of the networked settlement elevation calculation in the invention. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0055] The present invention provides a technical solution: an intelligent monitoring method for ground subsidence around a site during subway shield construction, comprising the following specific steps:

[0056] Step 1: Construction preparation and selection of appropriate intelligent monitoring equipment. The construction preparation is as follows:

[0057] According to the location where the shield tunnel passes through, the affected buildings are determined, and the degree of impact on the buildings is graded and classified. The specific classification is as follows:

[0058] Level 1 risk: buildings located directly above the tunnel shield construction route;

[0059] Level 2 risk: surface and underground buildings within 8-12m on both sides of the tunnel shield construction centerline;

[0060] Level 3 risk: surface and underground buildings 16-24m on both sides of the tunnel centerline;

[0061] Step 2: Determine the installation plan of the intelligent monitoring equipment. The intelligent monitoring equipment specifically adopts a static level, specifically a magnetostrictive hydrostatic level. The static level consists of a measuring rod, an electronic compartment, and a non-contact magnetic floating ball sleeved on the measuring rod. The measuring rod is equipped with a magnetostrictive wire, and the measuring rod is made of a non-magnetic stainless steel pipe;

[0062] The static level uses a circuit to generate a starting pulse. When the starting pulse is transmitted in the waveguide wire, a rotating magnetic field is generated along the direction of the waveguide wire. When the magnetic field meets the magnetic field in the float, a magnetostrictive effect is generated, causing the waveguide wire to twist. This twist is sensed by the electronic energy pickup mechanism and converted into a corresponding current pulse. The measuring circuit calculates the time difference between the two pulses, that is, the measured liquid level value. The static level adopts the "connecting tube" principle. After the liquid is injected into the U-shaped tube with openings at both ends, the liquid will remain at the same horizontal plane under the action of atmospheric pressure and gravity. The magnetostrictive static level is a non-contact liquid level measurement sensor; the measurement principle is to measure the distance from the emitting part inside the electronic compartment to the float, and calculate the level change of the liquid surface where the float is located; it is mainly used for vertical displacement monitoring, and has the characteristics of high resolution, high precision, high stability, high reliability, fast response time, and long working life;

[0063] The magnetostrictive static level uses a data acquisition instrument to collect data. The magnetostrictive static level is connected to the computer through wired or wireless communication to achieve automatic observation. The measured liquid level value collected by the acquisition instrument can be used to obtain its △H according to the method shown in the figure. i The size of , positive value means the measuring point floats up, negative value means the measuring point sinks, such as Figure 2 As shown;

[0064] The installation scheme of intelligent monitoring equipment is as follows:

[0065] The installation plan includes installation route planning, installation location determination, and installation quantity determination;

[0066] Installation route planning is used to ensure that the installation positions of intelligent monitoring equipment are on the same horizontal line;

[0067] The installation location is determined, including columns, shear walls, and foundation structures;

[0068] Installation quantity: The distance between adjacent intelligent monitoring devices ranges from 5 to 10 meters;

[0069] Step 3: Position and install the intelligent monitoring equipment. The specific steps are as follows:

[0070] S1. Use a laser level to determine the horizontal line on the installation surface according to the selected points, and determine the points and installation lines on the horizontal line at the same time;

[0071] S2. Use an impact drill to drill holes at the determined points, fix the bolts inside the holes, and fix the mounting plate with the bolts. The mounting plate must be aligned with the mounting line.

[0072] S3. Three nuts are installed in parallel on the fixed mounting plate. The nut in the middle is used for positioning the fixed mounting plate, and the other two nuts are used to adjust the horizontal height of the level by thread matching;

[0073] S4. After installing the level according to the above steps according to the measuring point, replace the vent screw on the side of the level with the liquid plug screw and tighten it;

[0074] S5. Connect all the level gauges using liquid pipes through the liquid pipe interface;

[0075] Step 4: Perform the liquid injection operation into the intelligent detection equipment. After the level gauge is installed, the short pipe needs to be injected with liquid. The length of the short pipe is less than 100m. The specific steps are as follows:

[0076] S1. Before filling the liquid, use a flat-blade screwdriver to loosen the plug screws on all the level gauges;

[0077] S2. Put the water pump into the bucket filled with antifreeze, connect the water pump to the left liquid pipe of the level gauge at the first measuring point, and put the right liquid pipe of the level gauge at the last measuring point into another empty container;

[0078] S3. After the scale of the first measuring point reaches 50-60, tighten the plug screw on the top of the device. The other static levels are filled with liquid in sequence according to the above steps until all the static levels are filled with liquid.

[0079] S4. When the liquid is pumped to the last measuring point, you need to first remove the right liquid tube and replace it with the short liquid tube placed here before pumping and plug it with a plug. When the scale of the level at the last measuring point reaches 50-60, tighten the upper plug screw;

[0080] S5. Unplug the long liquid tube connecting the water pump to the level gauge, then loosen the upper plug screw, wait for the antifreeze to flow out from the left side of the level gauge, use the short liquid tube to connect the left side of the upper measuring point, until the antifreeze fills the short liquid tube and then plugs the plug, and finally tighten the upper plug screw;

[0081] S6. After filling the level, remember to replace the filling plugs on the side of all measuring point level gauges with the original air vent screws;

[0082] Step 5: Install the corresponding data transfer devices, the number of which is set to one-fifth of the static level. Every five static levels are equipped with one data transfer device. The data transfer device uses six-channel and multi-channel data acquisition instruments, and realizes data collection, management, and transmission through the PC-side software and database platform, and performs real-time collection, timed collection, data drawing, data warning, and data export for the connected sensors;

[0083] The data transfer device includes a sensor, a signal conditioner, an analog-to-digital converter, a data storage device, and a communication interface;

[0084] The basic principles are as follows:

[0085] Sensor: It senses the change of physical quantity and converts it into electrical signal;

[0086] Signal conditioner: amplifies, filters, linearizes, and processes the electrical signals output by the sensor to ensure signal stability and accuracy;

[0087] Analog-to-digital converter: converts analog signals into digital signals for digital processing and storage;

[0088] Data storage: used to store collected data, including RAM, ROM, and FLASH;

[0089] Communication interface: used to transfer collected data to computers or other devices, including serial port, Ethernet, USB;

[0090] The data transfer device adopts solar charging mode, which can absorb sunlight energy through solar panels to charge, thus achieving energy self-sufficiency; this environmentally friendly and sustainable energy solution not only reduces operating costs, but also reduces environmental pollution;

[0091] There are two options for the connection between the data transfer device and the intelligent monitoring device: physical connection and wireless connection. The physical connection connects the device directly to the data transfer device through a cable, which is stable and reliable. The wireless connection allows the device to transmit data without a physical connection, which greatly improves the flexibility and convenience of the device. Through these two connection methods, we can choose the most appropriate connection method according to actual needs and environmental conditions to ensure real-time transmission and monitoring of data.

[0092] Step 6: Execute the data verification procedure. Data testing includes but is not limited to setting the frequency of data collection, real-time monitoring of data sending and receiving, and verification of data accuracy and reliability, to ensure that the data monitoring system is in good operating condition and can accurately complete the data collection, processing and analysis tasks. Through data testing, any problems that may exist in the system can be discovered and solved in a timely manner, thereby ensuring the smooth progress of the formal data collection process and the accuracy and effectiveness of subsequent data analysis;

[0093] Step 7: Analyze and judge the monitoring data, automatically identify and filter out the data records with problems, calculate the collected data, take the original value of the offset angle of each point, collect multiple times at different frequencies, compare and analyze with the original value and the previous value, and determine whether the settlement of the point meets the regulations. After the settlement of the point is determined, it is necessary to network and determine the settlement of an area to obtain the final result, such as Figure 3 As shown, an overall judgment is made based on the difference between the installed elevation reference line and the read elevation reference line, thereby determining whether the settlement of the area meets the requirements;

[0094] Table 1 Principles of Settlement Data Analysis

[0095] Serial number Types of risk areas Monitoring equipment 5 sets 1 Level 1 risk area 2 units have exceeded the settlement limit 2 Secondary risk area 3 units have exceeded the settlement limit 3 Level 3 risk area 5 units experienced excessive settlement

[0096] The over-limit standard can be manually set according to the building codes and standards of different regions to ensure that the analysis results can meet the specific needs of different regions. Such flexibility enables data analysis to more accurately serve the housing safety monitoring work in various regions;

[0097] Step 8: Classify and archive the monitoring data. After a short-term data analysis, the data is stored in the database platform backend in an orderly manner in the form of time series. The data is exported from the database platform for local storage. The house settlement data is automatically processed and predicted using time series analysis and regression analysis methods.

[0098] By classifying and archiving monitoring data, not only the data is stored in an orderly manner in the form of time series, but also the data is cleaned and denoised through algorithms to ensure data quality;

[0099] In order to improve the efficiency and accuracy of data analysis, time series analysis, regression analysis, etc. are used to automatically process and predict house settlement data, so as to capture subtle changes in the data, predict possible settlement trends in the future, and provide a scientific basis for decision makers.

[0100] Table 2 Types of device data formats

[0101]

[0102] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An intelligent monitoring method for ground settlement around a site during subway shield construction, characterized in that: The specific steps include: Step 1: Construction preparation and selection of appropriate intelligent monitoring equipment; Step 2: Determine the installation plan of the intelligent monitoring equipment. The intelligent monitoring equipment specifically uses a static level, specifically a magnetic static level; Step 3: Position and install the intelligent monitoring equipment. The specific steps are as follows: S1. Use a laser level to determine the horizontal line on the installation surface according to the selected point, and determine the point and installation line on the horizontal line at the same time; S2. Use an impact drill to drill holes at the determined points, fix the bolts inside the holes, and fix the mounting plate with the bolts. The mounting plate must be aligned with the mounting line. S3. Three nuts are installed in parallel on the fixed mounting plate. The nut in the middle is used for positioning the fixed mounting plate, and the other two nuts are used to adjust the horizontal height of the level by thread matching; S4. After installing the level according to the above steps according to the measuring point, replace the vent screw on the side of the level with the liquid plug screw and tighten it; S5. Connect all the level gauges using liquid pipes through the liquid pipe interface; Step 4: Perform the liquid injection operation into the intelligent detection equipment. After the level gauge is installed, the short pipe needs to be injected with liquid. The length of the short pipe is less than 100m. The specific steps are as follows: S1. Before filling the liquid, use a flat-blade screwdriver to loosen the plug screws on all the level gauges; S2. Put the water pump into the bucket filled with antifreeze, connect the water pump to the left liquid pipe of the level gauge at the first measuring point, and put the right liquid pipe of the level gauge at the last measuring point into another empty container; S3. After the scale of the first measuring point reaches 50-60, tighten the plug screw on the top of the device. The other static levels are filled with liquid in sequence according to the above steps until all the static levels are filled with liquid. S4. When the liquid is pumped to the last measuring point, you need to first remove the right liquid tube and replace it with the short liquid tube placed here before pumping and plug it with a plug. When the scale of the level at the last measuring point reaches 50-60, tighten the upper plug screw; S5. Unplug the long liquid tube connecting the water pump to the level gauge, then loosen the upper plug screw, wait for the antifreeze to flow out from the left side of the level gauge, use the short liquid tube to connect the left side of the upper measuring point, until the antifreeze fills the short liquid tube and then plugs the plug, and finally tighten the upper plug screw; S6. After filling the level, remember to replace the filling plugs on the side of all measuring point level gauges with the original air vent screws; Step 5: Install the corresponding data transfer devices, the number of which is set to one fifth of the static level, and one data transfer device is equipped for every five static levels; Step 6: Execute data verification procedures. Data testing includes but is not limited to setting the frequency of data collection, real-time monitoring of data transmission and reception, and verification of data accuracy and reliability; Step 7: Analyze and judge the monitoring data, automatically identify and filter out the data records with problems, calculate the collected data, take the original value of the offset angle of each point, collect multiple times at different frequencies, and compare and analyze with the original value and the previous value to determine whether the settlement of the point meets the requirements; Step 8: The monitoring data is classified and archived. After a short-term data analysis, the data is stored in the database platform backend in an orderly manner in the form of a time series. The data is exported from the database platform for local storage. The house settlement data is automatically processed and predicted using time series analysis and regression analysis methods.

2. The intelligent monitoring method for ground subsidence around a site during subway shield construction according to claim 1 is characterized in that: The construction preparation in step 1 is as follows: According to the location where the shield tunnel passes through, the affected buildings are determined, and the degree of impact on the buildings is graded and classified. The specific classification is as follows: Level 1 risk: buildings located directly above the tunnel shield construction route; Level 2 risk: surface and underground buildings within 8-12m on both sides of the tunnel shield construction centerline; Level 3 risk: surface and underground buildings within 16-24m on both sides of the tunnel centerline.

3. The intelligent monitoring method for ground subsidence around a site during subway shield construction according to claim 1 is characterized in that: The installation scheme of the intelligent monitoring equipment in step 2 is as follows: The installation plan includes installation route planning, installation location determination, and installation quantity determination; Installation route planning is used to ensure that the installation positions of intelligent monitoring equipment are on the same horizontal line; The installation location is determined, including columns, shear walls, and foundation structures; The installation quantity and the distance between adjacent intelligent monitoring devices are in the range of 5-10m.

4. The intelligent monitoring method for ground subsidence around a site during subway shield construction according to claim 1 is characterized in that: The static level in step 2 is composed of a measuring rod, an electronic compartment and a non-contact magnetic floating ball sleeved on the measuring rod, wherein a magnetostrictive wire is installed in the measuring rod, and the measuring rod is made of a non-magnetic stainless steel tube; The static level gauge generates a starting pulse by the circuit. When the starting pulse is transmitted in the waveguide wire, a rotating magnetic field is generated along the direction of the waveguide wire. When the magnetic field meets the magnetic field in the float, a magnetostrictive effect is generated, causing the waveguide wire to twist. This twisting is sensed by the electronic energy pickup mechanism and converted into a corresponding current pulse. The measuring circuit calculates the time difference between the two pulses, that is, the measured liquid level value.

5. The intelligent monitoring method for ground subsidence around a site during subway shield construction according to claim 1 is characterized in that: The data transfer device in step five adopts a six-channel and multi-channel data acquisition instrument, realizes data collection, management, and transmission through the PC-side software and database platform, and performs real-time collection, timed collection, data drawing, data warning, and data export on the connected sensors.

6. The intelligent monitoring method for ground subsidence around a site during subway shield construction according to claim 5 is characterized in that: The data transfer device includes a sensor, a signal conditioner, an analog-to-digital converter, a data storage device and a communication interface; The basic principles are as follows: Sensor: It senses the change of physical quantity and converts it into electrical signal; Signal conditioner: amplifies, filters, linearizes, and processes the electrical signals output by the sensor to ensure signal stability and accuracy; Analog-to-digital converter: converts analog signals into digital signals for digital processing and storage; Data storage: used to store collected data, including RAM, ROM, and FLASH; Communication interface: used to transfer the collected data to a computer or other device, including serial port, Ethernet, and USB.

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