Method for dynamically monitoring, regulating and controlling bubbles of aluminum film system concrete

Abstract

The invention relates to the technical field of concrete bubble monitoring, in particular to an aluminum film system concrete bubble dynamic monitoring and regulating method which comprises the following steps: applying a high-frequency alternating current with a first preset parameter to an aluminum film system to induce eddy current in an aluminum film and enable the aluminum film to generate thermally induced acoustic vibration; meanwhile, an eddy current thermally induced acoustic response signal reflected by an internal interface of the concrete is obtained; based on the response signal, determining current bubble state information in the concrete, including amplitude attenuation characteristics based on the sound pressure signal, frequency spectrum characteristics based on the sound pressure signal and phase delay information; and based on the bubble state information, a regulation and control instruction of a second preset parameter is generated, the regulation and control instruction is executed to adjust the parameter of the high-frequency alternating current applied to the aluminum film system, and directional traction regulation and control are conducted on the bubbles in the concrete. According to the invention, by means of an eddy current thermally induced sound technology, dynamic distribution, including the number, the particle size, the motion trail and the like, of bubbles is captured in real time, and instantaneous changes in the pouring process can be accurately reflected.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of concrete bubble monitoring, and particularly relates to an aluminum membrane system concrete bubble dynamic monitoring and regulation method. BACKGROUND

[0002] During the concrete pouring process, bubbles will be generated in the slurry due to insufficient vibration, improper material ratio or construction process defects. If the bubbles are not discharged in time, voids will be formed in the hardened concrete, resulting in reduced structural strength and decreased permeability resistance, and even causing cracks and other safety hazards. The existing bubble monitoring method relies on post-sampling detection or static monitoring of pre-embedded sensors, and cannot capture the dynamic distribution of bubbles in real time, making it difficult to reflect the instantaneous changes during the pouring process. Moreover, the sorting is mainly realized by manually adjusting the vibration frequency or prolonging the vibration time, which lacks targeted intervention on the position and motion state of the bubbles, and is prone to cause excessive vibration to cause aggregate segregation or local bubble residue. The aluminum membrane, as a new type of formwork, has the characteristics of fast heat conduction and smooth surface. The coupling between traditional vibration equipment and the aluminum membrane is poor, and bubbles are prone to accumulate near the aluminum membrane and difficult to discharge. SUMMARY

[0003] The present application provides an aluminum membrane system concrete bubble dynamic monitoring and regulation method to solve the technical problems in the prior art.

[0004] The technical solution of the present application to solve the above technical problems is as follows: an aluminum membrane system concrete bubble dynamic monitoring and regulation method, comprising the following steps: S101, applying a first preset parameter high-frequency alternating current to the aluminum membrane system to induce eddy current in the aluminum membrane and make it produce thermal acoustic vibration, and simultaneously acquiring the eddy current thermal acoustic response signal reflected back by the internal interface of the concrete; S102, determining the current bubble state information in the concrete based on the response signal, including the amplitude attenuation characteristics based on the sound pressure signal, the frequency spectrum characteristics based on the sound pressure signal and the phase delay information; S103, generating a second preset parameter regulation instruction based on the bubble state information, and executing the regulation instruction to adjust the parameters of the high-frequency alternating current applied to the aluminum membrane system, and performing directional traction regulation on the internal bubbles of the concrete.

[0005] In a preferred embodiment, the S101 applies a first preset parameter high-frequency alternating current to the aluminum membrane system. The alternating current generates eddy current in the aluminum membrane. The Joule heat of the eddy current causes the local rapid heating of the aluminum membrane, induces periodic thermal expansion and contraction, forms thermal acoustic vibration, and the eddy current is a circular current induced by the alternating magnetic field in the conductor. The strength value of the eddy current is directly related to the current frequency and amplitude. The Joule effect of the eddy current on the aluminum membrane resistance causes the local temperature of the aluminum membrane to change periodically, and the change frequency is consistent with the frequency of the applied alternating current. The piezoelectric sensor array is coupled to the surface of the aluminum film, and the ultrasonic coupling agent is uniformly coated between the sensor and the aluminum film, so as to ensure that the sound wave formed by the thermal-induced acoustic vibration is efficiently transmitted into the concrete. When the sound wave transmitted into the concrete meets the surface of the air bubble and the surface of the aggregate, the reflected sound pressure signal is positively correlated with the difference in acoustic impedance of the interface. The piezoelectric sensor array receives the sound pressure signal reflected by the interface in the concrete, filters and amplifies the collected sound pressure signal, retains the characteristic frequency band related to the air bubble, filters out the low-frequency noise by using a filter, and the specific calculation formula of the cutoff frequency of the filter is as follows: Wherein, R represents the resistance value in the filter circuit, and C represents the capacitance value in the filter circuit. The attenuation characteristics of the filter for different frequency signals are described by a transfer function as follows: Wherein, represents the frequency of the input signal, and j represents the imaginary unit. When , , the signal is not attenuated, and when , , the signal is significantly attenuated, noise filtering is achieved. Let the maximum amplitude of the original signal after filtering be , and the specific calculation formula of the dynamic gain G of the amplifier is as follows: Wherein, represents the maximum amplitude of the target output signal, and let the instantaneous signal value after filtering be , and the specific calculation formula of the output signal after amplification is as follows: The amplified signal needs to maintain the phase consistency with the original signal.

[0006] In a preferred embodiment, the S102 calculates the relative value of the air bubble number density by analyzing the amplitude attenuation characteristics of the sound pressure signal. When the sound wave propagates in the concrete, it will be scattered and energy-absorbed multiple times when meeting the air bubble group, resulting in a decrease in the amplitude of the reflected signal. The degree of amplitude attenuation is positively correlated with the air bubble number density. The concrete is divided into a first region close to the aluminum film and a second region away from the aluminum film. The second region is the main part of the concrete inside, and the distribution of air bubbles is more significantly affected by the vibration. The amplitude attenuation coefficients of the reflected signals in each region are calculated respectively. Let the initial sound pressure amplitude of the first region be ​​​The amplitude value of the sound pressure reflected back through the first region is The amplitude attenuation coefficient of the first region is The specific calculation formula of the amplitude attenuation coefficient is as follows: The initial amplitude value of the sound pressure of the second region is The amplitude value of the sound pressure reflected back through the second region is The amplitude attenuation coefficient of the second region is The specific calculation formula of the amplitude attenuation coefficient is as follows: The attenuation coefficient , The value range of the attenuation coefficient is The value of the attenuation coefficient is large, indicating that the bubble number density of the region is relatively high. By comparing the sizes of and , the bubble density of the two regions can be directly determined. The frequency characteristics and particle size of the scattered sound wave are used to determine the equivalent particle size distribution of the bubbles. When the bubble particle size is much smaller than the wavelength of the sound wave, the scattering intensity of the sound wave is proportional to the fourth power of the frequency, and the characteristic frequency of the scattered sound wave is negatively related to the bubble particle size. The inherent vibration frequency of small bubbles is high, and the scattering of high-frequency sound waves is stronger. The characteristic peak appears in the high-frequency band of the reflection signal. The inherent vibration frequency of large bubbles is low, and the characteristic peak is concentrated in the low-frequency band. The collected reflected sound pressure signal is converted into a frequency domain signal by Fourier transform to extract the frequency value of the characteristic peak. The specific calculation formula is as follows: Wherein, represents the frequency domain signal obtained after Fourier transform, j represents the imaginary unit, f represents the characteristic peak frequency extracted in the frequency domain signal, represents the time domain signal of the reflected sound pressure, represents the rotation factor in the complex domain, represents the angular frequency, and dt is used to represent the small change of the time variable. Each peak value corresponds to the scattering contribution of a type of bubble with a certain particle size. The frequency value of the characteristic peak is substituted into the preset calibration curve to determine the corresponding equivalent particle size. The specific calculation formula of the corresponding equivalent particle size d is as follows: Wherein, k represents the proportionality coefficient, and the particle size distribution is calculated by the peak value ratio of each peak. Suppose that m characteristic peaks are extracted in the frequency domain signal, and the amplitude of the i-th characteristic peak is |T( )|. The specific calculation formula of the total amplitude is as follows: Where Z represents the total amplitude, the specific formula for calculating the proportion of the particle size range corresponding to this characteristic peak is as follows: in, This indicates the proportion of the particle size range corresponding to the characteristic peak; Phase delay analysis is used to calculate the velocity vector of the air bubble. When the bubble moves within the concrete slurry, it causes a change in the path length of the sound wave propagation, resulting in a phase delay in the reflected signal. This phase delay is proportional to the bubble's velocity, and the phase of the sound wave propagating in the medium satisfies the equation: phase = ... Where b represents the propagation distance, The wavelength is represented by b. When the bubble moves in the concrete slurry, the relative distance between it and the surface of the aluminum film changes with time. If the bubble moves away from the aluminum film, b increases, the propagation distance of the reflected sound wave increases, and the phase delay increases. If it moves closer to the aluminum film, b decreases, and the phase delay decreases. By comparing the phase difference of the reflected signals at two adjacent moments and combining it with the propagation speed of the sound wave in the concrete, the velocity vector of the bubble in three-dimensional space is calculated. The phase difference is calculated by setting the wavelength in the concrete as... Bubbles at time The relative distance to the surface of the aluminum film is The phase of the corresponding reflected signal is At any moment The relative distance is The phase of the corresponding reflected signal is The relationship between phase and distance satisfies , Then the phase difference between the two moments The specific calculation formula is as follows: in, For the bubbles in - To obtain the three-dimensional velocity vector, the distance change over time requires at least three non-collinear piezoelectric sensors on the aluminum film surface. , By measuring the phase difference in different directions, three velocity components in orthogonal directions are obtained: The calculation of the velocity components in three orthogonal directions is based on assuming the velocity component along the x-axis of the aluminum film plane is... By sensor phase difference The calculation is as follows: Let the velocity component along the y-axis of the aluminum film plane be... By sensor phase difference The calculation is as follows: Let the velocity component along the z-axis of the aluminum film plane be... By sensor phase difference The calculation is as follows: In a preferred embodiment, in step S103, by dynamically adjusting the parameters of the high-frequency alternating current, based on the principle of acoustic flow effect, the high-frequency alternating current applied to the aluminum film will excite the aluminum film to vibrate, thereby radiating sound waves in the adjacent concrete medium and forming an acoustic flow field. This acoustic flow field can generate volume force on the bubbles, driving the bubbles to move in a directional manner. Based on the obtained particle size distribution and velocity components of the target bubble group, the amplitude, frequency and duty cycle of the current are adjusted in a targeted manner. Small bubbles require less traction force, so the current amplitude should be reduced to avoid excessive disturbance. Large bubbles require more traction force, so the current amplitude should be increased to enhance the acoustic flow field intensity. The acoustic flow field generated by high-frequency current has a shallow penetration depth and is suitable for bubble intervention in the first region. The acoustic flow field generated by low-frequency current has a deep penetration depth and is suitable for bubble intervention in the deep region. Based on the location of the preset vent hole, a path is planned to extend from the dense period of bubbles to the vent opening, and the current in the corresponding area of ​​the aluminum film is activated in sequence along this path. This operation will form a continuous channel with the highest acoustic flow field intensity in the concrete, namely a virtual vent channel. Under the directional thrust generated by the acoustic flow field, the bubbles are continuously guided to the vent hole location along this channel and finally discharged from the concrete body.

[0007] The beneficial effects of this invention are as follows: This invention utilizes eddy current thermoacoustic technology to capture the dynamic distribution of bubbles in real time, including their quantity, particle size, and trajectory. It can accurately reflect the instantaneous changes during the pouring process. By directionally guiding the bubbles through the acoustic flow field and combining the equivalent particle size distribution and velocity vector of the bubbles, the amplitude, frequency, and duty cycle of the high-frequency alternating current are dynamically adjusted. This avoids the blindness of traditional manual adjustment of vibration methods, reduces the problem of aggregate segregation caused by excessive vibration, and makes full use of the conductive and acoustic properties of the aluminum film. By coating the piezoelectric sensing array and the aluminum film with an ultrasonic coupling agent, the efficient transmission of acoustic energy is ensured. Attached Figure Description

[0008] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0009] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0010] In the description of the present application, the terms "first", "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise explicitly and specifically limited.

[0011] In the description of the present application, the term "for example" is used to indicate "as an example, illustration or description". Any embodiment described as "for example" in the present application is not necessarily interpreted as more preferred or more advantageous than other embodiments. The following description is given in order to enable any person skilled in the art to implement and use the present application. In the following description, details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art can realize the present application without using these specific details. In other examples, well-known structures and processes will not be described in detail in order to avoid unnecessary details making the description of the present application obscure. Therefore, the present application is not intended to be limited to the shown embodiments, but is consistent with the broadest scope in accordance with the principles and characteristics disclosed in the present application.

[0012] As Figure 1 The present embodiment provides a method for dynamically monitoring and regulating bubbles in an aluminum membrane system concrete, comprising the following steps: S101, applying a first preset parameter high-frequency alternating current to the aluminum membrane system to induce eddy current in the aluminum membrane and make it produce thermal acoustic vibration, and simultaneously acquiring the eddy current thermal acoustic response signal reflected by the internal interface of the concrete; Further, the first preset parameter high-frequency alternating current is applied to the aluminum membrane system, the eddy current is generated in the aluminum membrane by the alternating current, the Joule heat of the eddy current makes the local temperature of the aluminum membrane rise rapidly, periodic thermal expansion and contraction are triggered, thermal acoustic vibration is formed, the eddy current is a circular current induced by the alternating magnetic field in the conductor, the strength value of the eddy current is directly related to the current frequency and amplitude, the Joule effect of the eddy current on the aluminum membrane resistance causes the local temperature of the aluminum membrane to change periodically, and the change frequency is consistent with the applied alternating current frequency; The piezoelectric sensor array is coupled to the surface of the aluminum film, and the ultrasonic coupling agent is uniformly coated between the sensor and the aluminum film, so as to ensure that the sound wave formed by the thermal-induced acoustic vibration is efficiently transmitted into the concrete, the reflected sound pressure signal is positively correlated with the acoustic impedance difference of the interface, the piezoelectric sensor array receives the sound pressure signal reflected by the interface in the concrete, and the collected sound pressure signal is filtered and amplified to retain the characteristic frequency band related to the air bubble, the filter is used to filter out the low-frequency noise, and the specific calculation formula of the cut-off frequency is as follows: Wherein, R represents the resistance value in the filter circuit, C represents the capacitance value in the filter circuit, and the attenuation characteristics of the filter to different frequency signals are described by the transfer function , and the specific calculation formula is as follows: Wherein, represents the frequency of the input signal, j represents the imaginary unit, when , , , the signal is not attenuated, and when , , , the signal is significantly attenuated, noise filtering is realized, the maximum amplitude of the original signal after filtering is set as , and the specific calculation formula of the dynamic gain G of the amplifier is as follows: Wherein, represents the maximum amplitude of the target output signal, the instantaneous signal value after filtering is set as , and the specific calculation formula of the output signal after amplification is as follows: The amplified signal needs to maintain the phase consistency with the original signal.

[0013] It should be noted that the spacing of the sensor is set to 5-10 cm, which needs to meet two conditions, one is to cover the effective construction area of the aluminum film, to ensure that there is no monitoring blind area, and the other is that the detection range of adjacent sensors partially overlaps, the piezoelectric element in the array has a positive piezoelectric effect, which can convert the sound pressure signal into an electric signal, the ultrasonic coupling agent can eliminate the air gap between the sensor and the surface of the aluminum film, so that the sound wave generated by the thermal-induced acoustic vibration can be transmitted into the concrete, and the reflection loss of the sound energy at the interface is reduced, so that the sound wave can effectively reach the air bubble and the aggregate in the concrete.

[0014] S102, determine the current bubble state information inside the concrete based on the response signal, including the amplitude attenuation characteristics of the sound pressure signal, the frequency spectrum characteristics of the sound pressure signal and the phase delay information; Further, by analyzing the amplitude attenuation characteristics of the sound pressure signal to calculate the relative value of the bubble number density, when the sound wave propagates in the concrete, it will be scattered and energy absorbed by the bubble group, resulting in a decrease in the amplitude of the reflected signal, and the degree of amplitude attenuation is positively correlated with the bubble number density. The concrete is divided into a first area close to the aluminum film and a second area away from the aluminum film, the second area being the main part of the concrete inside, the bubble distribution being more significantly affected by the vibration and compaction. When the sound wave propagates in the concrete, the bubble as a gas-liquid interface will produce scattering and absorption, the more the number of bubbles, the greater the total scattering cross section, and the more significant the sound energy loss, resulting in a smaller amplitude of the sound pressure signal reflected to the surface of the aluminum film. Therefore, the degree of amplitude attenuation of the reflected signal is positively correlated with the bubble number density, and the amplitude attenuation coefficient of the reflected signal in each area is calculated respectively. Let the initial sound pressure amplitude of the first area be , the sound pressure amplitude reflected back by the first area be , and the amplitude attenuation coefficient of the first area be The specific calculation formula is as follows: Let the initial sound pressure amplitude of the second area be , the sound pressure amplitude reflected back by the second area be , and the amplitude attenuation coefficient of the second area be The specific calculation formula is as follows: The value range of the attenuation coefficient , is , and the value of the attenuation coefficient is large, indicating that the bubble number density in this area is relatively high. By comparing the size of and , the bubble density of the two areas can be directly determined. The frequency characteristics of the scattered sound wave and the correlation of the particle size are used to determine the equivalent particle size distribution of the bubbles. When the bubble particle size is much smaller than the wavelength of the sound wave, the scattering intensity of the bubble to the sound wave is proportional to the fourth power of the frequency, and the characteristic frequency of the scattered sound wave is negatively correlated with the bubble particle size. The inherent vibration frequency of small bubbles is high, and the scattering of high-frequency sound waves is stronger. The characteristic peak appears in the high-frequency band of the reflected signal spectrum. The inherent vibration frequency of large bubbles is low, and the characteristic peak is concentrated in the low-frequency band. The collected reflected sound pressure signal is converted to a frequency domain signal by Fourier transform to extract the frequency value of the characteristic peak. The specific calculation formula is as follows: wherein, represents the frequency domain signal obtained after Fourier transform, j represents the imaginary unit, and f represents the characteristic peak frequency extracted in the frequency domain signal, represents the time domain signal of the reflected sound pressure, represents the rotation factor in the complex domain, represents the angular frequency, and dt represents a small change in the time variable, wherein k represents a proportional coefficient, the value of which is determined by standard bubble sample experiment calibration, and is used to establish a quantitative correlation between the characteristic frequency and the particle size, and the particle size distribution is calculated by the peak value proportion of each peak. Assuming that m characteristic peaks are extracted in the frequency domain signal, the amplitude of the i-th characteristic peak is |T(i)|, and the specific calculation formula of the total amplitude is as follows: wherein Z represents the total amplitude, and the specific calculation formula of the proportion of the particle size interval corresponding to the characteristic peak is as follows: wherein, represents the proportion of the particle size interval corresponding to the characteristic peak; The phase delay analysis is used to calculate the bubble motion velocity vector. When the bubble moves in the concrete slurry, it causes a change in the sound wave propagation path length, resulting in a phase delay of the reflected signal. The phase delay is proportional to the bubble motion velocity, and the phase of the sound wave propagating in the medium satisfies the phase = b / f. wherein b represents the propagation distance, represents the wavelength. When the bubble moves in the concrete slurry, its relative distance from the aluminum film surface changes with time. If the bubble moves away from the aluminum film, b increases, the propagation distance of the reflected sound wave increases, and the phase delay increases. If the bubble moves towards the aluminum film, b decreases, the phase delay decreases. By comparing the phase difference of two adjacent time reflected signals and combining the sound wave propagation speed in the concrete, the motion velocity vector of the bubble in the three-dimensional space is calculated. The phase difference is calculated by setting the wavelength of the sound wave in the concrete as , the relative distance of the bubble from the aluminum film surface at time is , and the phase of the corresponding reflected signal is , the relative distance of the bubble from the aluminum film surface at time is , and the phase of the corresponding reflected signal is ​, the phase and distance meet , , the phase difference of two moments The specific calculation formula is as follows: Among them, is the distance change of the bubble in - Time, in order to obtain three-dimensional velocity vector, at least three non-collinear piezoelectric sensors (PZT) on the surface of the aluminum film are needed to measure the phase difference in different directions, and three orthogonal velocity components are obtained: , The calculation of three orthogonal velocity components is to set the velocity component along the x-axis direction of the aluminum film plane as , which is calculated by the phase difference of the sensor , and the specific calculation formula is as follows: Set the velocity component along the y-axis direction of the aluminum film plane as , which is calculated by the phase difference of the sensor , and the specific calculation formula is as follows: Set the velocity component along the z-axis direction of the aluminum film plane as , which is calculated by the phase difference of the sensor , and the specific calculation formula is as follows: It should be noted that the preset calibration curve is obtained by standard bubble sample experiment. Different frequency sound waves are emitted in the standard bubble group with known particle size, and the characteristic peak frequency corresponding to each particle size is recorded. The corresponding relationship between frequency and particle size is fitted.

[0015] S103, based on the bubble state information, generate a control instruction of the second preset parameter, and execute the control instruction to adjust the parameter of the high-frequency alternating current applied to the aluminum film system to control the directional traction of the bubbles in the concrete; Further, by dynamically adjusting the high-frequency alternating current parameter, based on the principle of acoustic streaming effect, the high-frequency alternating current applied to the aluminum film will excite the aluminum film to vibrate, thereby radiating sound waves in the adjacent concrete medium and forming an acoustic streaming field. The acoustic streaming field can generate a volume force on the bubble to drive the bubble to move directionally. Based on the obtained particle size distribution and motion velocity component of the target bubble group, the amplitude, frequency and duty cycle of the current are adjusted accordingly. ​Small bubbles require less traction force, so the current amplitude is reduced to avoid excessive disturbance. Large bubbles require more traction force, so the current amplitude is increased to enhance the acoustic flow field intensity. The acoustic flow field generated by high-frequency current has a shallow penetration depth and is suitable for bubble intervention in the first region. The acoustic flow field generated by low-frequency current has a deep penetration depth and is suitable for bubble intervention in the deep region. The duty cycle adjustment is intended to set the current to a pulsed output, for example, a duty cycle of 50%, i.e., 0.1s on and 0.1s off cycle. This intermittent working mode avoids continuous heating of the aluminum film, thereby controlling the local temperature of the concrete slurry to not exceed the preset temperature and preventing high temperature from adversely affecting the material properties. Based on the location of the preset vent hole, such as the 10mm hole reserved on the aluminum film, a path is planned to extend from the dense period of bubbles to the vent opening. The current in the corresponding area of ​​the aluminum film is activated in sequence along this path. This operation will form a continuous channel with the highest acoustic flow field intensity in the concrete, namely a virtual vent channel. Under the directional thrust generated by the acoustic flow field, the bubbles are continuously guided to the vent hole location along this channel and finally discharged from the concrete body.

[0016] It should be noted that adjusting the duty cycle is done to prevent the aluminum membrane from overheating by intermittent output, ensuring that the concrete slurry is kept within a safe range. Continuous high-frequency alternating current will cause eddy current Joule heating accumulation in the aluminum membrane, and the heat will enter the concrete slurry through heat conduction, potentially causing local temperatures to exceed 60°C. This temperature will disrupt the concrete hydration reaction. Setting the current to pulsed output can provide a heat dissipation window for the aluminum membrane while ensuring effective traction of the acoustic flow field. During power outages, the aluminum membrane dissipates heat through the air and the concrete slurry, and the temperature drops back to a safe range, avoiding the impact of continuous high temperatures on concrete performance. The temperature rise of the aluminum membrane within 0.1 seconds of power-on, such as from ambient temperature of 25°C to 55°C, and the temperature drop within 0.1 seconds of power-off, such as from 55°C to 30°C, form a dynamic balance, ensuring that the slurry temperature is always ≤60°C. The pulse period must be less than the relaxation time of the bubbles in the acoustic flow field. The time for the bubbles to continue moving due to inertia after traction stops is approximately 0.5 seconds, avoiding interruption of bubble movement due to pulse intervals.

[0017] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0018] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0019] The present application is described in reference to the flowchart and / or block diagrams of the methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each block of the flowchart and / or block diagrams, and combinations of blocks in the flowchart and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart and / or block diagram block or blocks. Figure 1 The flowchart and / or block diagrams can also be implemented by the Figure 1 means for carrying out any function specified in the flowchart and / or block diagram block or blocks.

[0020] These computer program instructions can also be stored in a computer- readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart and / or block diagram block or blocks. Figure 1 The flowchart and / or block diagrams can also be implemented by the Figure 1 means for carrying out any function specified in the flowchart and / or block diagram block or blocks.

[0021] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the function specified in the flowchart and / or block diagram block or blocks. Figure 1 The flowchart and / or block diagrams can also be implemented by the Figure 1 means for carrying out any function specified in the flowchart and / or block diagram block or blocks.

[0022] While the preferred embodiments of the application have been described, additional variations and modifications can be made to the embodiments by those of skill in the art once they have the benefit of the present disclosure. Therefore, the appended claims are intended to cover all such variations and modifications as falling within the scope of the application.

[0023] Obviously, numerous modifications and variations of the present application are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A method for dynamic monitoring and control of air bubbles in aluminum film-based concrete, characterized in that, Includes the following steps: S101. Apply a high-frequency alternating current with a first preset parameter to the aluminum film system to induce eddy currents in the aluminum film and cause it to generate thermo-acoustic vibration, while acquiring the eddy current thermo-acoustic response signal reflected back from the concrete internal interface. S102. Based on the response signal, determine the current bubble state information inside the concrete, including the amplitude attenuation characteristics based on the sound pressure signal, the spectral characteristics based on the sound pressure signal, and the phase delay information. S103. Based on the bubble state information, generate a control command for the second preset parameters, and execute the control command to adjust the parameters of the high-frequency alternating current applied to the aluminum film system, so as to perform directional traction control on the bubbles inside the concrete.

2. The method for dynamic monitoring and control of concrete bubbles in an aluminum film system according to claim 1, characterized in that, In step S101, a high-frequency alternating current with a first preset parameter is introduced into the aluminum film system. The alternating current generates eddy currents in the aluminum film. The Joule heating of the eddy currents causes the local temperature of the aluminum film to rise rapidly, inducing periodic thermal expansion and contraction, forming thermoacoustic vibration. Eddy currents are circular currents induced inside the conductor by the alternating magnetic field. Their intensity is directly related to the current frequency and amplitude. The Joule effect generated by the eddy currents on the aluminum film resistor causes the local temperature of the aluminum film to change periodically. The frequency of this change is consistent with the frequency of the applied alternating current. A piezoelectric sensor array is coupled to the surface of an aluminum film. An ultrasonic coupling agent is uniformly coated between the sensor and the aluminum film to ensure that the sound waves generated by thermally induced acoustic vibration are efficiently transmitted into the concrete. The sound waves transmitted into the concrete are reflected when they encounter the surface of air bubbles and aggregates. The amplitude of the reflected sound pressure signal is positively correlated with the difference in acoustic impedance at the interface. The piezoelectric sensor array receives the sound pressure signal reflected from the interface inside the concrete, filters and amplifies the collected sound pressure signal, and retains the characteristic frequency band related to air bubbles.

3. The method for dynamic monitoring and control of air bubbles in concrete using an aluminum film system according to claim 2, characterized in that, Low-frequency noise is removed using a filter, with a cutoff frequency of... The specific calculation formula is as follows: Where R represents the resistance value in the filter circuit, C represents the capacitance value in the filter circuit, and the attenuation characteristics of the filter for signals of different frequencies are expressed through the transfer function. The specific calculation formula is as follows: in, This represents the frequency of the input signal, and j represents the imaginary unit. At that time, | | The signal passes through without attenuation, when At that time, | | The signal is significantly attenuated, achieving noise filtering. Let the maximum amplitude of the original signal after filtering be... The specific formula for calculating the dynamic gain G of the amplifier is as follows: in, This represents the maximum amplitude of the target output signal. Let the value of the filtered instantaneous signal be... The amplified output signal The specific calculation formula is as follows: The amplified signal must maintain phase consistency with the original signal.

4. The method for dynamic monitoring and control of air bubbles in aluminum film system concrete according to claim 1, characterized in that, In step S102, the relative value of bubble number density is calculated by analyzing the amplitude attenuation characteristics of the sound pressure signal. When the sound wave propagates in the concrete, it will be scattered and absorbed multiple times when it encounters the bubble group, resulting in a decrease in the amplitude of the reflected signal. The degree of amplitude attenuation is positively correlated with the bubble number density. The concrete is divided into a first region close to the aluminum film and a second region far away from the aluminum film. The second region is the main part inside the concrete, and the bubble distribution is more significantly affected by vibration. The amplitude attenuation coefficient of the reflected signal in each region is calculated respectively.

5. The method for dynamic monitoring and control of concrete bubbles in an aluminum film system according to claim 4, characterized in that, Let the initial sound pressure amplitude of the first region be _____. The sound pressure amplitude reflected back from the first region is Then the amplitude attenuation coefficient of the first region The specific calculation formula is as follows: Let the initial sound pressure amplitude of the second region be _____. The sound pressure amplitude reflected back from the second region is Then the amplitude attenuation coefficient of the second region The specific calculation formula is as follows: Attenuation coefficient , The range of values ​​is A large attenuation coefficient indicates a relatively high number density of bubbles in the region. (This can be achieved through comparison.) and The size of the bubble can directly determine the density of bubbles in two regions; The equivalent particle size distribution of bubbles is determined by utilizing the correlation between the frequency characteristics of sound waves scattered by bubbles and their particle size. When the bubble particle size is much smaller than the wavelength of the sound wave, the scattering intensity of the sound wave by the bubble is proportional to the fourth power of the frequency, and the characteristic frequency of the scattered sound wave is negatively correlated with the bubble particle size. Small bubbles have higher natural vibration frequencies and scatter higher-frequency sound waves more strongly, resulting in characteristic peaks in the high-frequency band of the reflected signal spectrum. Large bubbles have lower natural vibration frequencies, and their characteristic peaks are concentrated in the low-frequency band. The collected reflected sound pressure signal is converted into a frequency domain signal through Fourier transform to extract the frequency values ​​of the characteristic peaks. The specific calculation formula is as follows: in, Let represent the frequency domain signal obtained after Fourier transform, where j represents the imaginary unit, and f represents the characteristic peak frequency extracted from the frequency domain signal. The time-domain signal representing the reflected sound pressure. The rotation factor of the complex field, Let dt represent the angular frequency, and dt represent the minute change in the time variable. Each peak corresponds to the bubble scattering contribution of a certain particle size. By substituting the frequency values ​​of the characteristic peaks into the preset calibration curve, the corresponding equivalent particle size can be determined. The specific calculation formula for the corresponding equivalent particle size d is as follows: Where k represents the proportionality coefficient, and the particle size distribution is calculated by the peak value ratio of each peak. Let m characteristic peaks be extracted from the frequency domain signal, and the amplitude of the i-th characteristic peak be |T( The specific formula for calculating the total amplitude is as follows: Where Z represents the total amplitude, the specific formula for calculating the proportion of the particle size range corresponding to this characteristic peak is as follows: in, This indicates the proportion of the particle size range corresponding to the characteristic peak.

6. The method for dynamic monitoring and control of air bubbles in concrete using an aluminum film system according to claim 5, characterized in that, Phase delay analysis is used to calculate the velocity vector of the air bubble. When the bubble moves within the concrete slurry, it causes a change in the path length of the sound wave propagation, resulting in a phase delay in the reflected signal. This phase delay is proportional to the bubble's velocity, and the phase of the sound wave propagating in the medium satisfies the equation: phase = ... Where b represents the propagation distance, The wavelength is represented by b. When the bubble moves in the concrete slurry, the relative distance between it and the surface of the aluminum film changes with time. If the bubble moves away from the aluminum film, b increases, the propagation distance of the reflected sound wave increases, and the phase delay increases. If it moves closer to the aluminum film, b decreases, and the phase delay decreases. By comparing the phase difference of the reflected signals at two adjacent moments and combining it with the propagation speed of the sound wave in the concrete, the velocity vector of the bubble in three-dimensional space is calculated.

7. The method for dynamic monitoring and control of concrete bubbles in an aluminum film system according to claim 6, characterized in that, The phase difference is calculated by setting the wavelength in the concrete as... Bubbles at time The relative distance to the surface of the aluminum film is The phase of the corresponding reflected signal is At any moment The relative distance is The phase of the corresponding reflected signal is The relationship between phase and distance satisfies , Then the phase difference between the two moments The specific calculation formula is as follows: in, For the bubbles in - To obtain the three-dimensional velocity vector, the distance change over time requires at least three non-collinear piezoelectric sensors on the aluminum film surface. , The phase difference in different directions was measured to obtain the velocity components in three orthogonal directions.

8. The method for dynamic monitoring and control of air bubbles in concrete using an aluminum film system according to claim 7, characterized in that, The calculation of the velocity components in three orthogonal directions is based on assuming the velocity component along the x-axis of the aluminum film plane is... By sensor phase difference The calculation is as follows: Let the velocity component along the y-axis of the aluminum film plane be... By sensor phase difference The calculation is as follows: Let the velocity component along the z-axis of the aluminum film plane be... By sensor phase difference The calculation is as follows: 。 9. The method for dynamic monitoring and control of air bubbles in concrete using an aluminum film system according to claim 1, characterized in that, In step S103, by dynamically controlling the parameters of the high-frequency alternating current, based on the principle of acoustic flow effect, the high-frequency alternating current applied to the aluminum film will excite the aluminum film to vibrate, thereby radiating sound waves in the adjacent concrete medium and forming an acoustic flow field. This acoustic flow field can generate volume force on the bubbles, driving the bubbles to move in a directional manner. Based on the obtained particle size distribution and velocity components of the target bubble group, the amplitude, frequency and duty cycle of the current are adjusted in a targeted manner. Small bubbles require less traction force, so the current amplitude should be reduced to avoid excessive disturbance. Large bubbles require more traction force, so the current amplitude should be increased to enhance the acoustic flow field intensity. The acoustic flow field generated by high-frequency current has a shallow penetration depth and is suitable for bubble intervention in the first region. The acoustic flow field generated by low-frequency current has a deep penetration depth and is suitable for bubble intervention in the deep region. Based on the location of the preset vent hole, a path is planned to extend from the dense period of bubbles to the vent hole. The current in the corresponding area of ​​the aluminum film is activated in sequence along this path. Under the directional thrust generated by the acoustic flow field, the bubbles are continuously guided to the vent hole location along the channel and finally discharged from the concrete body.

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