Tunnel deformation and vibration non-contact monitoring system and method

Abstract

The application provides a tunnel deformation and vibration non-contact monitoring system and method, and relates to the technical field of tunnel deformation and vibration monitoring.The system comprises a microwave transceiver, a control and processor, and a storage and output module.The microwave transceiver is used for simultaneously transmitting multi-channel linear frequency modulation continuous wave microwave signals through a transmitting antenna array, receiving echo signals, outputting multi-channel baseband signals, and realizing cyclic scanning of a synthetic beam through phase shift control of the transmitting antenna.The control and processor is used for controlling beam scanning of the microwave transceiver, baseband signal acquisition, and deformation and vibration displacement extraction of a measured point.The storage and output module is used for displaying or saving system scanning angle distribution and deformation and vibration displacement sequence values or waveforms of a measured point of a tunnel structure, identifying and removing information of abnormal working conditions, and transmitting relevant information to a data platform as required.The application can realize automatic monitoring of deformation and vibration displacement of all measured points in a tunnel profile and a line direction.

Description

Technical Field

[0001] This invention relates to the field of tunnel deformation and vibration monitoring technology, specifically to a non-contact monitoring system and method for tunnel deformation and vibration. Background Technology

[0002] The modern transportation system comprises infrastructure such as subways, high-speed railways, and expressways, with tunnels being a crucial component. Their safety during construction and operation is paramount. Under complex and variable geological conditions and environmental circumstances, tunnel structures are prone to deformation (including settlement). If settlement or deformation exceeds safety limits, it can easily lead to major safety accidents, seriously threatening economic and social development and the safety of people's lives and property. Furthermore, external impacts and vibrations can also cause vibration damage to tunnel structures. Therefore, 24 / 7 monitoring of tunnel structural deformation and vibration is an urgent engineering requirement.

[0003] To address the aforementioned needs, current main monitoring methods include static levels, total stations, and distributed fiber optic systems. Static levels are susceptible to factors such as temperature, delay effects, liquid materials, and air pressure. Total stations calculate deformation by measuring the relative coordinates of various reference points, but the measurement process is easily affected by terrain visibility and weather conditions, and requires manual single-point measurement. Distributed fiber optic tunnel deformation monitoring requires embedded fiber optic cables, which are difficult to install and maintain. Therefore, existing technologies and methods struggle to solve the challenges of multi-point, long-distance, and high-precision monitoring of tunnel profile and alignment deformation and vibration, and also face significant difficulties in terms of monitoring convenience, all-weather monitoring capabilities, and automation.

[0004] The invention patent with publication number CN109100735A discloses a subway tunnel deformation monitoring system and method, including: a central processing unit, a host, a monitoring module, a vibration sensor, a signal processing circuit, an A / D conversion module, an image acquisition module, and an image processing module; wherein, the vibration sensor is connected to the signal processing circuit, the signal processing circuit is connected to the A / D conversion module, the image acquisition module is connected to the image processing module, both the A / D conversion module and the image processing module are connected to the central processing unit, the central processing unit is bidirectionally connected to the host, and the monitoring module is connected to the central processing unit. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a non-contact monitoring system and method for tunnel deformation and vibration.

[0006] According to the present invention, a non-contact monitoring system and method for tunnel deformation and vibration is provided, the scheme of which is as follows:

[0007] In a first aspect, a non-contact monitoring system for tunnel deformation and vibration is provided, the system comprising:

[0008] Microwave transceiver: Used to simultaneously transmit multiple channels of linear frequency modulated continuous wave microwave signals through a transmitting antenna array, receive echo signals, output multi-channel baseband signals, and achieve cyclic scanning of the synthesized beam through phase shift control of the transmitting antenna;

[0009] Control and Processor: Used to control the beam scanning of the microwave transceiver, baseband signal acquisition, and deformation and vibration displacement extraction of the measured points;

[0010] Storage and output module: Used to display or save, but not limited to, the system scanning angle distribution, deformation and vibration displacement sequence values ​​or waveforms of the measured points of the tunnel structure, identification and rejection information of abnormal working conditions, and to transmit relevant information to the data platform as needed.

[0011] Preferably, the microwave transceiver includes: a linear frequency modulated continuous wave microwave signal source, a power divider, a mixer, a phase shifter, an amplifier, a transmitting antenna array, and a receiving antenna array;

[0012] The signal source is connected to the power divider, with one part connected to the phase shifter to radiate the signal through the transmitting antenna, and the other part used as the local oscillator signal for mixing. The phase shifter is connected to the transmitting antenna and is used to adjust the main lobe of the synthesized beam transmitted by the transmitting antenna array to a set scanning angle through phase shift control. The receiving antenna array is connected to the amplifier, and the amplified output signal is connected to the mixer, where it is mixed with the local oscillator signal to output a multi-channel baseband signal. The number of phase shifters is equal to the number of transmitting antennas, and the phase shifters can also be time delay lines or other devices with phase shift control functions.

[0013] Preferably, the arrangement of the transmitting antenna array and the receiving antenna array is as follows: when monitoring the tunnel profile, based on the distribution of the monitoring points of the tunnel structure and the installation position of the microwave transceiver, the transmitting and receiving antenna arrays in the angular distribution direction need to be arranged according to the distribution direction of the monitoring points of the tunnel profile.

[0014] When monitoring the deformation and vibration of measuring points along the tunnel alignment, transmitting and receiving antenna arrays must be arranged according to the tunnel alignment. When monitoring both the tunnel profile and the alignment, a combination of antennas must be arranged in both directions. The transmitting antenna array must have at least two transmitting antennas, and the spacing between the transmitting antennas can be equal or unequal. The receiving antenna array must have at least one receiving antenna, and the spacing between the receiving antennas can be equal or unequal.

[0015] Preferably, the control and processor includes: a scanning control unit and a signal acquisition and processing unit;

[0016] The scanning control unit is used for phase shift control of the transmitting antenna channel, control of the cyclic scanning period, and control of other conventional parameters of the microwave transceiver; the phase shift control is achieved through the configuration of phase shifters connected to each transmitting antenna.

[0017] The signal acquisition and processing unit is used to synchronously acquire multi-channel baseband signals and extract the deformation and vibration displacement values ​​of the target or measuring point through processing of the acquired baseband signals; the signal processing unit also includes the identification and rejection of abnormal working conditions.

[0018] Preferably, the data transmission method of the storage and output module includes: wired transmission of analog output and digital communication, as well as Bluetooth, Wi-Fi, wireless network or other wireless transmission methods.

[0019] Secondly, a non-contact monitoring method for tunnel deformation and vibration is provided, the method comprising:

[0020] Step S1: Based on the distribution of monitoring points in the tunnel structure and the installation location of the microwave transceiver, determine the scanning angle direction sequence of the transmitted synthetic beam of the microwave transceiver;

[0021] Step S2: The microwave transceiver sequentially controls the transmission of the synthetic beam toward the sequence elements of the scanning angle direction, while simultaneously receiving the echo signal and acquiring the generated baseband signal;

[0022] Step S3: Process the acquired baseband signal. Based on the principle of phase interferometry and nonlinear demodulation, extract the deformation and vibration displacement values ​​of the measurement points of each scanning angle direction sequence element in sequence.

[0023] Step S4: Based on the above steps, perform cyclic scanning measurements at certain intervals to obtain time history signals of deformation and vibration displacement at all monitoring points.

[0024] Preferably, in step S2, the microwave transceiver uses phase shift control to cause the transmitting antenna array to transmit a synthesized beam, with the main lobe of the synthesized beam pointing towards the scanning angle direction. The beam scanning angle control method is as follows:

[0025] Let the scanning angle direction sequence be [θ1,…θ s ,…θ S If s = 1, 2, ..., S, then the scanning angle direction is θ. s At that time, with the first transmitting antenna as the reference point, the phase shift control elements or phase shifters of each antenna in the transmitting antenna array are set to 0 and 2πd²sinθ, respectively. i / λ c ,…,2πd K sinθ i / λc ;

[0026] In the formula, d k (n=2,…K) represents the distance between the k-th transmitting antenna and the first transmitting antenna, λ c θ is the wavelength corresponding to the center frequency of a linearly frequency-modulated continuous wave. s The beam scanning angle is referenced to the central axis. Each transmitting antenna transmits a linear frequency modulated continuous wave (LFM) signal or other signals equivalent to LFM.

[0027] Preferably, in step S3, extracting the deformation and vibration displacement values ​​of the measurement points for each scanning angle direction sequence element includes:

[0028] Each transmitting antenna transmits a linear frequency modulated continuous wave. Based on the principle of phase interferometry, the deformation and vibration displacement values ​​x(p,θ) of the sequence elements at a certain scanning angle direction during a certain scanning period are extracted using a nonlinear demodulation method. s The calculation is as follows:

[0029]

[0030] In the formula, x(p,θ) s iT sweep This represents the p-th cyclic scan, with a transmission sweep period of i and scan angle direction sequence elements of θ. s The deformation and vibration displacement values ​​of the corresponding measuring points, T sweep The frequency sweep period for transmitting a linear frequency modulated continuous wave via the transmitting antenna is defined as follows: arg[·] represents the operation of taking complex phase values, N is the number of single-channel baseband signal elements in each frequency sweep period, n is the index of the single-channel baseband signal element in each frequency sweep period, and T is the number of elements. s The sampling frequency and time of the baseband signal, s B (p,θ s iT,nT s ) represents the p-th cyclic scan, with the scan angle direction sequence element being θ. s The matrix consists of the baseband signals from the M receiving antenna channels during the i-th transmit sweep cycle. The column vectors of the matrix represent the baseband signals of the m-th channels (m = 1, 2, ..., M), where j is the imaginary unit. d is the estimated beat frequency corresponding to the distance between the measured point and the measured point. rxm (m=1,…,M) represent the distances from the m-th receiving antenna to the first receiving antenna, where d rx1 =0,λ c This represents the wavelength corresponding to the center frequency of a linearly frequency-modulated continuous wave. The aforementioned nonlinear demodulation calculation method can also be transformed into other demodulation calculation formulas without changing its fundamental nature.

[0031] The number of emission cycles i for each scanning angle is a positive integer equal to or greater than 1. When it is greater than 1, x(p,θ) is used as needed. s Take x(p,θ) within multiple transmit frequency sweep cycles of the current scan period. s iT sweep The average or optimal value of the sequence, or other selected values.

[0032] Preferably, in step S4, obtaining the time history signals of deformation and vibration displacement of all monitoring points through cyclic scanning includes:

[0033] Let θ be the sequence element of the scanning angle direction corresponding to a certain monitoring point. s The deformation and vibration displacement time history signal sequence of the monitoring point is [x(1,θ s ),…,x(p,θ s ),…],where s=1,2,…,S are the element indices of the scanning angle direction sequence, p=1,2,…,P are the cyclic scanning cycle indices, and the time interval of the time history signal sequence is the cyclic scanning cycle.

[0034] Preferably, the method further includes handling special working conditions: under long-term monitoring, for interference caused by non-contact measurement due to special working conditions including but not limited to vehicle passage and personnel passage in the tunnel, abnormal data caused by special working conditions are identified and removed.

[0035] Identification methods include, but are not limited to, judging abnormal increases in the amplitude of the baseband signal, dynamic changes, abnormal increases in the peak value of the spectrum, and rapid and large fluctuations in the displacement value of the measurement point, or judging based on special working conditions.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. This invention realizes non-contact automated monitoring of deformation and vibration displacement at multiple measurement points in the tunnel profile, as well as settlement and vibration displacement along the tunnel alignment.

[0038] 2. The system and method proposed in this invention solve the problem that multiple measurement points in tunnel profiles cannot be detected using a single microwave transceiver by means of microwave beamforming scanning deformation and vibration measurement. At the same time, it solves the limitation of needing to install targets including corner reflectors in the measurement of micro-wave deformation and vibration in tunnel profiles and line directions.

[0039] 3. The system and method proposed in this invention can overcome the coupling clutter interference from other targets in the microwave detection field of view through scanning beam synthesis measurement, which greatly enhances the signal strength of the measured point and improves the measurement accuracy, signal-to-noise ratio and detection distance.

[0040] 4. The system proposed in this invention only requires a microwave transceiver to complete the deformation and vibration displacement monitoring of the tunnel profile and the line direction, and does not require the installation of targets including corner reflectors. It is easy to operate and convenient in engineering, and has a high degree of automation. Attached Figure Description

[0041] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0042] Figure 1 This is a flowchart of the non-contact monitoring method for tunnel deformation and vibration of the present invention;

[0043] Figure 2 This is a schematic diagram of the non-contact monitoring system and method for tunnel deformation and vibration of the present invention;

[0044] Figure 3 This is a structural block diagram of the tunnel deformation and vibration non-contact monitoring system of the present invention;

[0045] Figure 4 This is a structural block diagram of a microwave transceiver according to an embodiment of the present invention;

[0046] Figure 5 This is a schematic diagram of the microwave transceiver antenna array arrangement during the measurement of deformation and vibration at tunnel cross-section measuring points according to an embodiment of the present invention. Detailed Implementation

[0047] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0048] This invention provides a non-contact monitoring method for tunnel deformation and vibration, referring to... Figure 1 and Figure 2 As shown, the method specifically includes the following steps:

[0049] Step S1: Based on the distribution of monitoring points in the tunnel structure and the installation location of the microwave transceiver, determine the scanning angle direction sequence of the transmitted synthetic beam of the microwave transceiver. For example... Figure 2 As shown, five measuring points are displayed, corresponding to the scanning angles of four tunnel profile measuring points and one tunnel alignment measuring point.

[0050] Step S2: The microwave transceiver sequentially controls the transmission of a synthetic beam toward the sequence elements of the scanning angle direction, while simultaneously receiving echo signals and acquiring the generated baseband signal.

[0051] The microwave transceiver uses phase shift control to enable the transmitting antenna array to emit a synthesized beam. The main lobe of the synthesized beam faces the scanning angle direction. The beam scanning angle control method is as follows:

[0052] Let the scanning angle direction sequence be [θ1,…θ s ,…θ S If s = 1, 2, ..., S, then the scanning angle direction is θ. s At that time, with the first transmitting antenna as the reference point, the phase shift control elements or phase shifters of each antenna in the transmitting antenna array are set to 0 and 2πd²sinθ, respectively. i / λ c ,…,2πd K sinθ i / λ c ;

[0053] In the formula, d k (n=2,…K) represents the distance between the k-th transmitting antenna and the first transmitting antenna, λ c θ is the wavelength corresponding to the center frequency of a linearly frequency-modulated continuous wave. s The beam scanning angle is referenced to the central axis. Each transmitting antenna transmits a linear frequency modulated continuous wave (LFM) signal or other signals equivalent to LFM.

[0054] Step S3: Process the acquired baseband signal. Based on the principle of phase interferometry and nonlinear demodulation, extract the deformation and vibration displacement values ​​of the measurement points of each scanning angle direction sequence element in sequence.

[0055] The extraction of the deformation and vibration displacement values ​​of the measurement points for each scanning angle direction sequence element includes:

[0056] Each transmitting antenna transmits a linear frequency modulated continuous wave. Based on the principle of phase interferometry, the deformation and vibration displacement values ​​x(p,θ) of the sequence elements at a certain scanning angle direction during a certain scanning period are extracted using a nonlinear demodulation method. s The calculation is as follows:

[0057]

[0058] In the formula, x(p,θ) s iT sweep This represents the p-th cyclic scan, with a transmission sweep period of i and scan angle direction sequence elements of θ. s The deformation and vibration displacement values ​​of the corresponding measuring points, T sweep The frequency sweep period for transmitting a linear frequency modulated continuous wave via the transmitting antenna is defined as follows: arg[·] represents the operation of taking complex phase values, N is the number of single-channel baseband signal elements in each frequency sweep period, n is the index of the single-channel baseband signal element in each frequency sweep period, and T is the number of elements.s The sampling frequency and time of the baseband signal, s B (p,θ s iT,nT s ) represents the p-th cyclic scan, with the scan angle direction sequence element being θ. s The matrix consists of the baseband signals from the M receiving antenna channels during the i-th transmit sweep cycle. The column vectors of the matrix represent the baseband signals of the m-th channels (m = 1, 2, ..., M), where j is the imaginary unit. d is the estimated beat frequency corresponding to the distance between the measured point and the measured point. rxm (m=1,…,M) represent the distances from the m-th receiving antenna to the first receiving antenna, where d rx1 =0,λ c This represents the wavelength corresponding to the center frequency of a linearly frequency-modulated continuous wave. The aforementioned nonlinear demodulation calculation method can also be transformed into other demodulation calculation formulas without changing its fundamental nature.

[0059] The number of emission cycles i for each scanning angle is a positive integer equal to or greater than 1. When it is greater than 1, x(p,θ) is used as needed. s Take x(p,θ) within multiple transmit frequency sweep cycles of the current scan period. s iT sweep The average or optimal value of the sequence, or other selected values.

[0060] Step S4: Based on the above steps, perform cyclic scanning measurements at certain intervals to obtain time history signals of deformation and vibration displacement at all monitoring points.

[0061] In this step, the time history signals of deformation and vibration displacement of all monitoring points are obtained through cyclic scanning, including:

[0062] Let θ be the sequence element of the scanning angle direction corresponding to a certain monitoring point. s The deformation and vibration displacement time history signal sequence of the monitoring point is [x(1,θ s ),…,x(p,θ s ),…],where s=1,2,…,S are the element indices of the scanning angle direction sequence, p=1,2,…,P are the cyclic scanning cycle indices, and the time interval of the time history signal sequence is the cyclic scanning cycle.

[0063] Handling of special working conditions: Under long-term monitoring, special working conditions in the tunnel, including but not limited to vehicle passage and personnel passage, can easily cause interference to non-contact measurements. We will identify and remove abnormal data caused by special working conditions, thereby improving the reliability and automation of monitoring.

[0064] Identification methods include, but are not limited to, judging abnormal increases in the amplitude of the baseband signal, dynamic changes, abnormal increases in the peak value of the spectrum, and rapid and large fluctuations in the displacement value of the measurement point, or judging based on special working conditions.

[0065] The aforementioned non-contact monitoring method for tunnel deformation and vibration, through synthetic beam scanning measurement, requires only a microwave transceiver to complete the monitoring of deformation and vibration displacement at all measuring points along the tunnel profile and the route direction. Furthermore, it does not require the installation of targets, including corner reflectors, and is easy to operate and convenient in engineering.

[0066] This invention provides a non-contact monitoring system for tunnel deformation and vibration, referring to... Figure 3 As shown, it specifically includes:

[0067] Microwave transceiver: Used to simultaneously transmit multiple channels of linear frequency modulated continuous wave microwave signals through a transmitting antenna array, receive echo signals, output multiple channels of baseband signals, and achieve cyclic scanning of the synthesized beam through phase shift control of the transmitting antenna.

[0068] Reference Figure 4 As shown, the microwave transceiver includes: a linear frequency modulated continuous wave microwave signal source, a power divider, a mixer, a phase shifter, an amplifier, a transmitting antenna array, and a receiving antenna array. The signal source is connected to the power divider, and a portion of it is connected to the phase shifter, radiating the signal through the transmitting antenna; the other portion serves as the local oscillator signal for mixing. The phase shifter is connected to the transmitting antenna and is used to adjust the main lobe of the synthesized beam transmitted by the transmitting antenna array towards a set scanning angle through phase shift control. The receiving antenna array is connected to the amplifier, and the amplified output signal is connected to the mixer, where it is mixed with the local oscillator signal to output a multi-channel baseband signal. The number of phase shifters is equal to the number of transmitting antennas; the phase shifters can also be time delay lines or other devices with phase shift control functions.

[0069] The arrangement of the transmitting and receiving antenna arrays is as follows: Based on the distribution of monitoring points along the tunnel structure and the installation location of the microwave transceivers, when monitoring the tunnel profile, the transmitting and receiving antenna arrays must be arranged according to the angular distribution direction of the monitoring points along the tunnel profile, such as... Figure 5 As shown, when monitoring the deformation and vibration of measuring points along the tunnel alignment, transmitting and receiving antenna arrays must be arranged according to the tunnel alignment direction. When monitoring both the tunnel profile and the alignment direction simultaneously, a combination of antennas in both directions is required. The transmitting antenna array must have at least two transmitting antennas, spaced evenly or unequally. The receiving antenna array must have at least one receiving antenna, spaced evenly or unequally. In actual monitoring, deformation and vibration monitoring of tunnel profile measuring points and tunnel alignment measuring points can be conducted separately as needed.

[0070] Control and Processor: Used to control the beam scanning of the microwave transceiver, baseband signal acquisition, and deformation and vibration displacement extraction of the measured points.

[0071] The control and processor include: a scanning control unit and a signal acquisition and processing unit.

[0072] The scanning control unit is used for phase shift control of the transmitting antenna channels, control of the cyclic scanning period, and control of other conventional parameters of the microwave transceiver. The phase shift control is achieved through the configuration of phase shifters connected to each transmitting antenna. The signal acquisition and processing unit is used for synchronous acquisition of multi-channel baseband signals, and for processing the acquired baseband signals to extract the vibration and deformation displacement values ​​of the measured target or measurement point. The signal processing unit also includes the identification and rejection of abnormal operating conditions.

[0073] Storage and output module: Used to display or save, but not limited to, the system scanning angle distribution, deformation and vibration displacement sequence values ​​or waveforms of the measured points of the tunnel structure, identification and rejection information of abnormal working conditions, and to transmit relevant information to the data platform as needed.

[0074] The data transmission methods of the storage and output modules include, but are not limited to: wired transmission methods for analog output and digital communication, as well as Bluetooth, Wi-Fi, wireless networks or other wireless transmission methods.

[0075] This invention provides a non-contact monitoring system and method for tunnel deformation and vibration. Based on the distribution of monitoring points on the tunnel structure and the installation location of the microwave transceiver, the scanning angle direction sequence of the transmitted synthetic beam of the microwave transceiver is determined. The microwave transceiver sequentially controls the transmission of synthetic beams oriented towards the elements of the scanning angle direction sequence, while simultaneously receiving echo signals and acquiring the generated baseband signal. The acquired baseband signal is processed, and based on the principle of phase interferometry and nonlinear demodulation, the deformation and vibration displacement values ​​of each monitoring point are sequentially extracted. According to the above method, cyclic scanning measurements are performed at certain periodic intervals to obtain the time history signals of deformation and vibration displacement of all monitored points, realizing automated monitoring of deformation and vibration displacement of all monitoring points along the tunnel profile and track direction. Through microwave beam synthesis scanning deformation and vibration measurement, the problem of not being able to detect multiple monitoring points on the tunnel profile using a single microwave transceiver is solved (see [link to relevant documentation]). Figure 2 This method not only solves the limitation of requiring targets, including corner reflectors, in the measurement of micro-waveform changes and vibrations in tunnel profiles and along the railway line, but also overcomes the interference of coupling clutter from other targets in the microwave detection field of view due to the scanning beamforming measurement method. This significantly enhances the signal strength of the measured point and improves the measurement accuracy, signal-to-noise ratio, and detection range.

[0076] Those skilled in the art will understand that, besides implementing the system and its various devices, modules, and units provided by this invention in the form of purely computer-readable program code, the same functions can be achieved entirely through logical programming of the method steps, making the system and its various devices, modules, and units of this invention function in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers. Therefore, the system and its various devices, modules, and units provided by this invention can be considered as a hardware component, and the devices, modules, and units included therein for implementing various functions can also be considered as structures within the hardware component; alternatively, the devices, modules, and units for implementing various functions can be considered as both software modules implementing the method and structures within the hardware component.

[0077] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A non-contact monitoring method for tunnel deformation and vibration, characterized in that, include: Step S1: Based on the distribution of monitoring points in the tunnel structure and the installation location of the microwave transceiver, determine the scanning angle direction sequence of the transmitted synthetic beam of the microwave transceiver; Microwave transceiver: Used to simultaneously transmit multiple channels of linear frequency modulated continuous wave microwave signals through a transmitting antenna array, receive echo signals, and output multiple channels of baseband signals; The number of transmitting antennas in the transmitting antenna array must be greater than or equal to 2, and the number of receiving antennas in the receiving antenna array of the microwave transceiver must be greater than or equal to 1. Step S2: The microwave transceiver sequentially controls the transmission of a composite beam oriented toward the sequence elements of the scanning angle direction, while simultaneously receiving echo signals and acquiring the generated baseband signal; the microwave transceiver uses phase shift control to cause the transmitting antenna array to transmit the composite beam, with the main lobe of the composite beam oriented toward the scanning angle direction; Step S3: Process the acquired baseband signal. Based on the principle of phase interferometry, extract the deformation and vibration displacement values ​​of the sequence elements of a certain scanning angle direction in a certain scanning period through nonlinear demodulation method. Step S4: Based on the above steps, perform cyclic scanning measurements at certain intervals to obtain time history signals of deformation and vibration displacement at all monitoring points.

2. The non-contact monitoring method for tunnel deformation and vibration according to claim 1, characterized in that, In step S2, the microwave transceiver uses phase shift control to cause the transmitting antenna array to transmit a synthesized beam. The main lobe of the synthesized beam faces the scanning angle direction. The beam scanning angle control method is as follows: Let the scanning angle direction sequence be [θ1, θ2, ... θ s ,…,θ S If s = 1, 2, ..., s, ..., S, then the scanning angle direction is... At that time, taking the first transmitting antenna as the reference point, the phase shift control elements or phase shifters setpoints for each antenna in the transmitting antenna array are as follows: ； In the formula, Let be the distance between the k-th transmitting antenna and the first transmitting antenna. , θ is the wavelength corresponding to the center frequency of a linear frequency modulated continuous wave. i The beam scanning angle is based on the central axis; the signals transmitted by each transmitting antenna are linear frequency modulated continuous wave signals or other signals equivalent to linear frequency modulated continuous wave signals.

3. The non-contact monitoring method for tunnel deformation and vibration according to claim 2, characterized in that, In step S3, the extraction of the deformation and vibration displacement values ​​of the measurement points of a sequence element in a certain scanning angle direction during a certain scanning period using a nonlinear demodulation method includes: The vibration displacement value The calculation formula is: In the formula, Represented as the first The next cyclic scanning cycle, the transmit frequency sweep cycle is... The scan angle direction sequence elements are The deformation and vibration displacement values ​​at the corresponding measuring points The frequency sweep period is the period for transmitting a linear frequency modulated continuous wave via the transmitting antenna. arg[·] represents the operation of taking complex phase values, N is the number of single-channel baseband signal elements in each frequency sweep period, and n is the index of the single-channel baseband signal element in each frequency sweep period. The sampling frequency and time of the baseband signal. For the first The second cycle of scanning, the scan angle direction sequence elements are... , No. A matrix consisting of baseband signals from M receive antenna channels across M transmit sweep cycles is given by the matrix's column vectors. The baseband signal of the channel, The imaginary unit, This is the estimated beat frequency corresponding to the distance between the measured point and the measured point. and are the distances from the m-th receiving antenna to the first receiving antenna, respectively. , The wavelength corresponding to the center frequency of a linear frequency modulated continuous wave; Number of emission cycles per scan angle It is a positive integer equal to or greater than 1. When it is greater than 1, it is determined according to the needs. Take the time of multiple transmit frequency sweep cycles in the current scan period The average or optimal value of the sequence, or other selected values.

4. The non-contact monitoring method for tunnel deformation and vibration according to claim 3, characterized in that, In step S4, the time history signals of deformation and vibration displacement of all monitoring points are obtained through cyclic scanning measurement, including: Let the scan angle direction sequence elements corresponding to a certain monitoring point be... The time history signal sequence of deformation and vibration displacement at the monitoring point is as follows: In the formula The element index of the scan angle direction sequence. The cyclic scan period number is the time interval of the time history signal sequence.

5. The non-contact monitoring method for tunnel deformation and vibration according to claim 1, characterized in that, The method also includes handling special working conditions: under long-term monitoring, in response to interference from non-contact measurement caused by special working conditions such as vehicle passage and personnel passage in the tunnel, the method identifies and removes abnormal data caused by special working conditions. The identification methods include judging abnormal increases in the amplitude of the baseband signal, abnormal increases in the peak value of the spectrum, and rapid fluctuations in the displacement value of the measurement point.

6. A non-contact monitoring system for tunnel deformation and vibration, characterized in that, The system employs the non-contact monitoring method for tunnel deformation and vibration as described in any one of claims 1-5, including: Microwave transceiver: Achieves cyclic scanning of the synthesized beam through phase shift control of the transmitting antenna; Control and Processor: Used to control the beam scanning of the microwave transceiver, baseband signal acquisition, and deformation and vibration displacement extraction of the measured points; Storage and output module: Used to display or save system scanning angle distribution and deformation and vibration displacement sequence values ​​or waveforms of the measured points of the tunnel structure, information on the identification and elimination of abnormal working conditions, and to transmit relevant information to the data platform as needed.

7. The non-contact monitoring system for tunnel deformation and vibration according to claim 6, characterized in that, The microwave transceiver includes: a linear frequency modulated continuous wave microwave signal source, a power divider, a mixer, a phase shifter, an amplifier, a transmitting antenna array, and a receiving antenna array. The signal source is connected to the power divider, part of which is connected to the phase shifter to radiate the signal through the transmitting antenna, and the other part is used as the local oscillator signal for mixing; the phase shifter is connected to the transmitting antenna and is used to adjust the main lobe of the synthetic beam transmitted by the transmitting antenna array to a certain set scanning angle through phase shift control; the receiving antenna array is connected to the amplifier, and the output amplified signal is connected to the mixer, where it is mixed with the local oscillator signal to output a multi-channel baseband signal; The number of phase shifters is equal to the number of transmitting antennas, and the phase shifters can use time delay lines or other devices with phase shift control functions.

8. The non-contact monitoring system for tunnel deformation and vibration according to claim 7, characterized in that, The arrangement of the transmitting and receiving antenna arrays is as follows: based on the distribution of the monitoring points of the tunnel structure and the installation position of the microwave transceiver, when monitoring the tunnel profile, the transmitting and receiving antenna arrays in the angular distribution direction of the monitoring points on the tunnel profile need to be arranged according to the distribution direction of the monitoring points on the tunnel profile. When monitoring the deformation and vibration of measuring points along the tunnel alignment, it is necessary to arrange the transmitting and receiving antenna arrays in that direction according to the tunnel alignment. When monitoring both the tunnel profile and the route direction, the receiving antennas need to be arranged in a combination in both directions; the distance between the receiving antennas can be equal or unequal.

9. The non-contact monitoring system for tunnel deformation and vibration according to claim 7, characterized in that, The control and processor includes: a scanning control unit and a signal acquisition and processing unit; The scanning control unit is used for phase shift control of the transmitting antenna channel, control of the cyclic scanning period, and control of other conventional parameters of the microwave transceiver; the phase shift control is achieved through the configuration of phase shifters connected to each transmitting antenna. The signal acquisition and processing unit is used to synchronously acquire multi-channel baseband signals and extract the vibration and deformation displacement values ​​of the target or measuring point through processing of the acquired baseband signals; the signal acquisition and processing unit also includes the identification and rejection of abnormal working conditions.

10. The non-contact monitoring system for tunnel deformation and vibration according to claim 6, characterized in that, The data transmission methods of the storage and output module include: wired transmission methods for analog output and digital communication, as well as Bluetooth, Wi-Fi, wireless network or other wireless transmission methods.

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