Piezoelectric intelligent composite rib and concrete long-term bonding performance monitoring system

Abstract

According to the piezoelectric intelligent composite rib and concrete long-term bonding performance monitoring system provided by the invention, long-term continuous stress monitoring is carried out on the direct contact action between the concrete and the piezoelectric intelligent composite rib by utilizing piezoelectric detection, and the relative displacement state between the piezoelectric patch sensor and the fiber composite rib is utilized to monitor the long-term bonding performance of the piezoelectric intelligent composite rib and the concrete. The adsorption acting force of the concrete is identified, the bonding performance between the fiber composite material rib and the concrete is monitored and identified from multiple aspects, and long-term continuous monitoring of the bonding performance between the fiber composite material rib and the concrete and accurate positioning of a bonding performance degradation area are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of civil engineering monitoring, and particularly to a piezoelectric intelligent composite bar and concrete long-term bonding performance monitoring system. BACKGROUND

[0002] Reinforced concrete structure is the main structure of modern buildings, in which steel bars serve as the support framework and play a decisive role in the structural stability and seismic resistance of buildings. Although steel bars are important structural materials for buildings, their heavy weight and susceptibility to corrosion severely limit the application of reinforced concrete structures in different building situations. Fiber composite bars (i.e., fiber-reinforced composite bars) have high mechanical strength, light weight, corrosion resistance, and fatigue resistance, and have gradually been applied to building construction. In special situations such as underwater buildings, fiber composite bars have been widely used as substitutes for steel bars. The regular thread structure on the surface of the fiber composite bar makes it difficult for the concrete to fully fill the gaps between the thread structures on the surface of the fiber composite bar after the fiber composite bar is poured with concrete, resulting in insufficient close contact between the surface of the fiber composite bar and the concrete. After long-term service of the fiber composite bar-concrete structure, the concrete on the surface of the fiber composite bar will gradually peel off, reducing the bonding and continuity of the surface of the fiber composite bar and the concrete, thereby affecting the safety of the overall fiber composite bar-concrete structure. Therefore, it is necessary to continuously monitor the bonding performance between the fiber composite bar and the concrete in the fiber composite bar-concrete structure. SUMMARY

[0003] The present application aims to provide a piezoelectric intelligent composite bar and concrete long-term bonding performance monitoring system that distinguishes between collecting and analyzing the electrical signals of all piezoelectric intelligent composite bars embedded in the concrete, obtains dynamic pressure data between the concrete and the piezoelectric intelligent composite bar in the corresponding direction, and identifies the pressure action between the concrete and the piezoelectric intelligent composite bar in multiple dimensions. From the dynamic pressure data analysis, the contact force change characteristic information between the surface of the piezoelectric intelligent composite bar and the concrete and the movement state characteristic information of the piezoelectric patch sensor on the surface of the fiber composite bar are obtained to determine the stress change information between the surface of the piezoelectric intelligent composite bar and the concrete and the adsorption force state information of the concrete region in contact with the piezoelectric intelligent composite bar, thereby determining the region of bonding performance degradation between the concrete and the piezoelectric intelligent composite bar. The piezoelectric detection is used to continuously monitor the direct contact action between the concrete and the piezoelectric intelligent composite bar, and the relative displacement state between the piezoelectric patch sensor and the fiber composite bar is used to identify the adsorption force of the concrete, thereby monitoring and identifying the bonding performance between the composite bar and the concrete from multiple aspects and accurately positioning the bonding performance degradation region.

[0004] The present application is achieved by the following technical solutions:

[0005] A piezoelectric intelligent composite bar and concrete long-term bonding performance monitoring system comprises:

[0006] An electric signal acquisition module is configured to collect electric signals from different piezoelectric intelligent composite bars based on spatial distribution information of all piezoelectric intelligent composite bars embedded in the concrete, and obtain a plurality of electric signal sets corresponding to different directions; wherein the piezoelectric intelligent composite bars comprise a fiber composite bar and a plurality of piezoelectric patch sensors distributed on the surface of the fiber composite bar.

[0007] An electric signal processing module is configured to pre-process and convert the electric signal sets, and obtain dynamic pressure data between the concrete and the piezoelectric intelligent composite bars in the concrete with respect to corresponding directions.

[0008] A first analysis module is configured to perform first analysis on the dynamic pressure data, and determine contact force change characteristic information between the surface of the piezoelectric intelligent composite bar and the concrete.

[0009] A second analysis module is configured to perform second analysis on the dynamic pressure data, and determine movement state characteristic information of the piezoelectric patch sensors on the surface of the fiber composite bar.

[0010] A stress action recognition module is configured to determine stress action change information between the surface of the piezoelectric intelligent composite bar and the concrete based on the contact force change characteristic information.

[0011] An adsorption action recognition module is configured to determine adsorption force state information of a concrete region in contact with the piezoelectric intelligent composite bar based on the movement state characteristic information.

[0012] An abnormal region determination module is configured to determine a region with deteriorated bonding performance between the concrete and the piezoelectric intelligent composite bar based on the stress action change information and the adsorption force state information.

[0013] Optionally, the electric signal acquisition module is configured to collect electric signals from different piezoelectric intelligent composite bars based on spatial distribution information of all piezoelectric intelligent composite bars embedded in the concrete, and obtain a plurality of electric signal sets corresponding to different directions, comprising:

[0014] The embedded position information and the orientation posture information of all piezoelectric intelligent composite bars embedded in the concrete are obtained, and the concrete is divided into a plurality of first composite bar distribution regions and a plurality of second composite bar distribution regions based on the embedded position information; wherein the distribution density of piezoelectric intelligent composite bars in the first composite bar distribution region is greater than that in the second composite bar distribution region.

[0015] Collecting electric signals generated by the piezoelectric smart composite bars under the first and second composite bar distribution areas with different signal collection sensitivities; based on the orientation information, all the collected electric signals are distinguished and integrated to obtain a first electric signal set and a second electric signal set corresponding to the horizontal and vertical orientation attitudes.

[0016] Optionally, the piezoelectric smart composite bar and long-term bonding performance monitoring system of concrete further comprises:

[0017] extracting the area of the first composite bar distribution area;

[0018] extracting the area of the second composite bar distribution area;

[0019] extracting the number of electric signals generated by the piezoelectric smart composite bars under the first composite bar distribution area;

[0020] extracting the number of electric signals generated by the piezoelectric smart composite bars under the second composite bar distribution area;

[0021] acquiring the signal collection sensitivity corresponding to the first composite bar distribution area by using the area of the first composite bar distribution area and the number of electric signals generated by the piezoelectric smart composite bars under the first composite bar distribution area;

[0022] wherein the signal collection sensitivity corresponding to the first composite bar distribution area is acquired by the following formula:

[0023]

[0024] wherein, L 01 represents the signal collection sensitivity corresponding to the first composite bar distribution area; L c represents a preset initial sensitivity value; S 01 represents the area of the first composite bar distribution area; S 02 represents the area of the second composite bar distribution area; n represents the number of electric signals generated by the piezoelectric smart composite bars under the first composite bar distribution area; and m represents the number of electric signals generated by the piezoelectric smart composite bars under the second composite bar distribution area.

[0025] acquiring the signal collection sensitivity corresponding to the second composite bar distribution area by using the area of the second composite bar distribution area and the number of electric signals generated by the piezoelectric smart composite bars under the second composite bar distribution area;

[0026] wherein the signal collection sensitivity corresponding to the second composite bar distribution area is acquired by the following formula:

[0027]

[0028] wherein, L 02 represents the signal acquisition sensitivity corresponding to the second composite bar distribution area; L c represents the preset initial value of sensitivity; S 01 represents the area of the first composite bar distribution area; S 02 represents the area of the second composite bar distribution area; n represents the number of electric signals generated by the piezoelectric intelligent composite bars under the first composite bar distribution area; and m represents the number of electric signals generated by the piezoelectric intelligent composite bars under the second composite bar distribution area.

[0029] Optionally, the electric signal processing module is configured to perform preprocessing and conversion processing on the set of electric signals to obtain dynamic pressure data between the concrete and the piezoelectric intelligent composite bars inside the concrete with respect to corresponding directions, including:

[0030] After performing interference noise filtering preprocessing on all electric signals under the set of electric signals, the all electric signals under the set of electric signals are subjected to conversion processing to obtain dynamic pressure data between the piezoelectric intelligent composite bars at different embedded position points in the concrete and the concrete in the horizontal direction and the vertical direction; wherein the dynamic pressure data refers to dynamic pressure data between the piezoelectric intelligent composite bars at the embedded position points and the concrete in a continuous time interval exceeding a preset time length threshold.

[0031] Optionally, the first analysis module is configured to perform first analysis on the dynamic pressure data to determine contact force change characteristic information between the surface of the piezoelectric intelligent composite bars and the concrete, including:

[0032] The dynamic pressure data between the piezoelectric intelligent composite bars at all embedded position points in the concrete and the concrete in the horizontal direction is analyzed to determine pressure action change characteristic information of the piezoelectric intelligent composite bar surface stress from the concrete, which is used as the contact force change characteristic information; wherein the pressure action change characteristic information includes the change characteristic information of the pressure action size of the piezoelectric intelligent composite bar surface stress from the concrete with time.

[0033] Optionally, the second analysis module is configured to perform second analysis on the dynamic pressure data to determine movement state characteristic information of the piezoelectric patch sensor on the surface of the fiber composite bar, including:

[0034] analyzing dynamic pressure data corresponding to the piezoelectric smart composite material rib and the concrete in the vertical direction at all embedded position points in the concrete to determine fluctuation and change characteristic information of the dynamic pressure data; wherein the fluctuation and change characteristic information of the pressure data includes interval time information of fluctuation of pressure values corresponding to the piezoelectric smart composite material rib and the concrete in the vertical direction;

[0035] determining movement displacement change characteristic information of the piezoelectric patch sensor on the surface of the fiber composite rib based on the fluctuation and change characteristic information of the dynamic pressure data, so as to the movement state characteristic information.

[0036] Optionally, the stress action recognition module is configured to determine stress action change information between the surface of the piezoelectric smart composite material rib and the concrete based on the contact action force change characteristic information, including:

[0037] analyzing pressure action size change characteristic information of the piezoelectric smart composite material rib surface from the concrete contained in the contact action force change characteristic information based on the sensing area size of the piezoelectric patch sensor on the surface of the piezoelectric smart composite material rib to determine the stress action change information between the surface of the piezoelectric smart composite material rib and the concrete; wherein the stress action change information includes stress action size change information between the surface of the piezoelectric smart composite material rib and the concrete over time.

[0038] Optionally, the adsorption action recognition module is configured to determine adsorption action force state information of a concrete region in contact with the piezoelectric smart composite material rib based on the movement state characteristic information, including:

[0039] determining an average movement speed of the piezoelectric patch sensor on the surface of the fiber composite rib based on the movement displacement change characteristic information of the piezoelectric patch sensor contained in the movement state characteristic information;

[0040] determining the adsorption action force state information of the concrete region in contact with the piezoelectric smart composite material rib based on the average movement speed; wherein the adsorption action force state information includes adsorption action force size distribution information of the concrete region in contact with the piezoelectric smart composite material rib along the length direction of the piezoelectric smart composite material rib.

[0041] Optionally, the abnormal region determination module is configured to determine a region with deteriorated bonding performance between the piezoelectric smart composite material rib and the concrete inside the concrete based on the stress action change information and the adsorption action force state information, including:

[0042] judge whether the position point of the embedded piezoelectric smart composite bar in the concrete is in a state of weakened bonding force between the concrete and the surface of the piezoelectric smart composite bar based on the stress change information and the adsorption force state information.

[0043] determine the area of the bonding performance deterioration between the concrete and the piezoelectric smart composite bar based on all the position points in the concrete in the state of weakened bonding force.

[0044] Compared with the prior art, the piezoelectric smart composite bar and the concrete long-term bonding performance monitoring system has the following beneficial effects:

[0045] The piezoelectric smart composite bar and the concrete long-term bonding performance monitoring system provided by the application distinguishes, collects and analyzes the electric signals of all the piezoelectric smart composite bars embedded in the concrete, obtains the dynamic pressure data of the concrete and the piezoelectric smart composite bar in the corresponding direction, and identifies the pressure action between the concrete and the piezoelectric smart composite bar in multiple dimensions. The contact force change characteristic information between the surface of the piezoelectric smart composite bar and the concrete and the movement state characteristic information of the piezoelectric patch sensor on the surface of the fiber composite bar are obtained from the dynamic pressure data analysis, so as to determine the stress change information between the surface of the piezoelectric smart composite bar and the concrete and the adsorption force state information of the concrete area in contact with the piezoelectric smart composite bar, thereby determining the area of the bonding performance deterioration between the concrete and the piezoelectric smart composite bar. The piezoelectric detection is used for long-term and continuous stress monitoring of the direct contact action between the concrete and the piezoelectric smart composite bar. The relative displacement state between the piezoelectric patch sensor and the fiber composite bar is used for identifying the adsorption force of the concrete, so as to monitor and identify the bonding performance between the composite bar and the concrete from multiple aspects, and realize the accurate positioning of the bonding performance deterioration area. BRIEF DESCRIPTION OF DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only show some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor. Among them:

[0047] Figure 1 The structure schematic diagram of the piezoelectric smart composite bar and the concrete long-term bonding performance monitoring system provided by the application.

[0048] Figure 2 The structure schematic diagram of the piezoelectric smart composite bar in the piezoelectric smart composite bar and the concrete long-term bonding performance monitoring system provided by the application.

[0049] The drawings show that: 1, fiber composite bar; 2, piezoelectric patch sensor. DETAILED DESCRIPTION

[0050] In order to make the above objectives, features and advantages of the present application more clear and comprehensible, specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. It can be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application. In addition, it should be noted that, for the purpose of description, only parts related to the present application are shown in the drawings, rather than all structures. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0051] The terms "comprising" and "having" and any variations thereof herein are intended to cover a non-exclusive inclusion. For example, a process, system, system, product or device that comprises a list of steps or units is not limited to the listed steps or units, but can optionally further include steps or units not listed, or can optionally further include other steps or units inherent to such processes, systems, products or devices.

[0052] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase that the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of other embodiments. It is explicitly contemplated that embodiments described herein can be combined with other embodiments.

[0053] Please refer to Figure 1 As shown in the drawings, an embodiment of the present application provides a piezoelectric smart composite bar and concrete long-term bonding performance monitoring system. The piezoelectric smart composite bar and concrete long-term bonding performance monitoring system comprises:

[0054] The electric signal acquisition module is configured to distinguish and collect the electric signals from different piezoelectric smart composite bars based on the spatial distribution information of all the piezoelectric smart composite bars embedded in the concrete, and obtain a plurality of electric signal sets corresponding to different directions; wherein the piezoelectric smart composite bar comprises a fiber composite bar and a plurality of piezoelectric patch sensors discretely distributed on the surface of the fiber composite bar; the structure of the piezoelectric smart composite bar is as shown in Figure 2As shown, the fiber composite tendon serves as the main structure of the piezoelectric intelligent composite tendon, and the surface is regularly and uniformly distributed with thread structures, and the convex part of the thread structure is uniformly distributed with a plurality of piezoelectric patch sensors in the circumferential direction. Each piezoelectric patch sensor serves as an independent sensing unit. When the piezoelectric patch sensor is subjected to the action of the concrete covering the surface of the fiber composite tendon, an electric signal in the form of voltage will be generated, and transmitted to the external terminal for further analysis and processing through the signal line connected by itself. The fiber composite tendon and the piezoelectric patch sensor both belong to commonly used devices in the art, and will not be described in detail here.

[0055] The electric signal processing module is configured to pre-process and convert the electric signal set to obtain dynamic pressure data of the concrete and the piezoelectric intelligent composite tendon inside the concrete with respect to a corresponding direction.

[0056] The first analysis module is configured to perform first analysis on the dynamic pressure data to determine contact force change characteristic information between the surface of the piezoelectric intelligent composite tendon and the concrete.

[0057] The second analysis module is configured to perform second analysis on the dynamic pressure data to determine movement state characteristic information of the piezoelectric patch sensor on the surface of the fiber composite tendon.

[0058] The stress action recognition module is configured to determine stress action change information between the surface of the piezoelectric intelligent composite tendon and the concrete based on the contact force change characteristic information.

[0059] The adsorption action recognition module is configured to determine adsorption force state information of a concrete region in contact with the piezoelectric intelligent composite tendon based on the movement state characteristic information.

[0060] The abnormal region determination module is configured to determine a region with deteriorated bonding performance between the piezoelectric intelligent composite tendon and the concrete inside the concrete based on the stress action change information and the adsorption force state information.

[0061] The piezoelectric smart composite bar and the long-term bonding performance monitoring system of the concrete have the beneficial effects that the piezoelectric smart composite bars embedded in the concrete are distinguished to collect and analyze the electrical signals of all the piezoelectric smart composite bars embedded in the concrete, dynamic pressure data about corresponding directions between the concrete and the piezoelectric smart composite bars are obtained, and the pressure action between the concrete and the piezoelectric smart composite bars is identified in multiple dimensions; the contact force change characteristic information between the surface of the piezoelectric smart composite bar and the concrete and the movement state characteristic information of the piezoelectric patch sensor on the surface of the fiber composite bar are obtained through dynamic pressure data analysis, so as to determine the stress change information between the surface of the piezoelectric smart composite bar and the concrete and the adsorption force state information of the concrete region in contact with the piezoelectric smart composite bar, thereby determining the area of the bonding performance deterioration between the concrete and the piezoelectric smart composite bar, using piezoelectric detection to continuously monitor the direct contact action between the concrete and the piezoelectric smart composite bar, and using the relative displacement state between the piezoelectric patch sensor and the fiber composite bar to identify the adsorption force of the concrete, the bonding performance between the composite bar and the concrete is monitored and identified from multiple aspects, and the accurate positioning of the bonding performance deterioration area is realized.

[0062] In another embodiment, the electrical signal collection module is used to distinguish and collect the electrical signals from different piezoelectric smart composite bars based on the spatial distribution information of all the piezoelectric smart composite bars embedded in the concrete, to obtain a plurality of electrical signal sets corresponding to different directions, including:

[0063] The embedding position information and the orientation attitude information of all the piezoelectric smart composite bars embedded in the concrete are obtained, the interior of the concrete is divided into a plurality of first composite bar distribution areas and a plurality of second composite bar distribution areas based on the embedding position information, and the distribution density of the piezoelectric smart composite bars in the first composite bar distribution area is greater than the distribution density of the piezoelectric smart composite bars in the second composite bar distribution area.

[0064] The electrical signals generated by the piezoelectric smart composite bars in the first composite bar distribution area and the second composite bar distribution area are collected with different signal collection sensitivities, and all the collected electrical signals are distinguished and integrated based on the orientation attitude information to obtain a first electrical signal set and a second electrical signal set corresponding to horizontal orientation attitudes and vertical orientation attitudes.

[0065] The piezoelectric smart composite bar has the same effect as the steel bar in the concrete, and different piezoelectric smart composite bars are first assembled into column structures, beam structures and other different types of structures, so that the piezoelectric smart composite bars have different distribution densities in different regions of the concrete, so that a large number of piezoelectric smart composite bars (i.e., a large number of piezoelectric patch sensors) exist in a part of the region of the concrete, and a small number of piezoelectric smart composite bars (i.e., a small number of piezoelectric patch sensors) exist in another part of the region of the concrete. The piezoelectric patch sensors on the piezoelectric smart composite bars in the same region generate electrical signals for the interaction between the concrete and the piezoelectric smart composite bars in the same region, so that the electrical signals generated by the piezoelectric patch sensors in the same region are redundant (i.e., a large number of the same electrical signals represent the interaction between the concrete and the piezoelectric smart composite bars in the same region), and if the subsequent processing of the electrical signals requires a large amount of time and computing power, in order to reduce the redundancy of the electrical signals generated by the piezoelectric patch sensors in the same region and take into account the comprehensive coverage of the electrical signals to the corresponding region in the concrete, based on the embedded position information of all piezoelectric smart composite bars in the concrete, the distribution density of the piezoelectric smart composite bars in different regions of the concrete is determined, if the distribution density of the piezoelectric smart composite bars in a region is greater than or equal to a preset density threshold, the corresponding region is determined as a first composite bar distribution region; if the distribution density of the piezoelectric smart composite bars in a region is less than the preset density threshold, the corresponding region is determined as a second composite bar distribution region. And collect the electrical signals generated by the piezoelectric smart composite bars under the first composite bar distribution region with a lower signal acquisition sensitivity, and collect the electrical signals generated by the piezoelectric smart composite bars under the second composite bar distribution region with a higher signal acquisition sensitivity, which can effectively remove the useless electrical signals of the piezoelectric smart composite bars under the first composite bar distribution region, and reduce the time and computing power of subsequent electrical signal processing. In addition, the piezoelectric smart composite bars are placed in the concrete in a horizontal orientation and a vertical orientation, and the concrete has different effects on the piezoelectric smart composite bars placed in the horizontal orientation and the vertical orientation. Therefore, based on the orientation information, all collected electrical signals are distinguished and integrated to obtain a first electrical signal set and a second electrical signal set corresponding to the horizontal orientation and the vertical orientation, which facilitates subsequent targeted analysis of the interaction between the piezoelectric smart composite bars in the horizontal orientation and the vertical orientation and the concrete.

[0066] In another embodiment, the piezoelectric smart composite bar and concrete long-term bonding performance monitoring system further comprises:

[0067] Extract the area of the first composite bar distribution region corresponding to the region;

[0068] Extract the area of the second composite bar distribution region corresponding to the region;

[0069] extracting the number of electric signals generated by the piezoelectric smart composite bars under the first composite bar distribution area;

[0070] extracting the number of electric signals generated by the piezoelectric smart composite bars under the second composite bar distribution area;

[0071] acquiring the signal collection sensitivity corresponding to the first composite bar distribution area by using the area of the first composite bar distribution area and the number of electric signals generated by the piezoelectric smart composite bars under the first composite bar distribution area;

[0072] wherein the signal collection sensitivity corresponding to the first composite bar distribution area is acquired by the following formula:

[0073]

[0074] wherein L 01 represents the signal collection sensitivity corresponding to the first composite bar distribution area; L c represents the preset initial value of the sensitivity; S 01 represents the area of the first composite bar distribution area; S 02 represents the area of the second composite bar distribution area; n represents the number of electric signals generated by the piezoelectric smart composite bars under the first composite bar distribution area; and m represents the number of electric signals generated by the piezoelectric smart composite bars under the second composite bar distribution area.

[0075] acquiring the signal collection sensitivity corresponding to the second composite bar distribution area by using the area of the second composite bar distribution area and the number of electric signals generated by the piezoelectric smart composite bars under the second composite bar distribution area;

[0076] wherein the signal collection sensitivity corresponding to the second composite bar distribution area is acquired by the following formula:

[0077]

[0078] wherein L 02 represents the signal collection sensitivity corresponding to the second composite bar distribution area; L c represents the preset initial value of the sensitivity; S 01 represents the area of the first composite bar distribution area; S 02 represents the area of the second composite bar distribution area; n represents the number of electric signals generated by the piezoelectric smart composite bars under the first composite bar distribution area; and m represents the number of electric signals generated by the piezoelectric smart composite bars under the second composite bar distribution area.

[0079] The above-mentioned embodiments have the beneficial effect that the signal collection sensitivity (L 01and L 02 ), which can fully consider the influence of the distribution density of piezoelectric smart composite bars (i.e., the number of electrical signal generation n and m) and the area (S 01 and S 02 ) in different regions. This sensitivity calculation method based on area and number of electrical signals can more accurately reflect the real monitoring capability of each region, thereby improving the monitoring sensitivity of the entire system. Especially under complex stress or environmental changes, the system can more sensitively capture the slight changes in the structure state, providing the possibility for early warning and timely intervention. Since the system can perform differential analysis according to the signal acquisition sensitivity of different regions, it can more accurately evaluate the bonding state between the piezoelectric smart composite bars and the concrete. This differential evaluation method helps to reduce monitoring errors caused by regional differences and improves the accuracy of monitoring results. In addition, through the accumulation and analysis of long-term monitoring data, the system can further modify and optimize the sensitivity calculation formula, making the monitoring results more close to the actual situation. This scheme introduces a preset initial value L c for sensitivity and dynamically adjusts the signal acquisition sensitivity in combination with actual monitoring data, effectively improving the reliability of the monitoring system. Even in extreme environments or abnormal working conditions, the system can maintain stable monitoring performance through adaptive adjustment, avoiding monitoring failure caused by a single factor. This scheme is suitable for different types of piezoelectric smart composite bars and concrete structures, with strong universality and adaptability. Whether it is a large bridge, a high-rise building, or other complex structures, the system can achieve comprehensive monitoring of the structure state through flexible configuration and adjustment. This adaptability not only reduces the application threshold of the system, but also improves its promotional value in different fields. By integrating signal acquisition, processing, and analysis functions, this scheme realizes intelligent monitoring of the bonding performance between piezoelectric smart composite bars and concrete. The system can automatically extract and analyze monitoring data to generate intuitive monitoring reports and warning information, providing convenient and efficient decision support for managers. This level of intelligence not only improves monitoring efficiency, but also reduces the cost and risk of manual intervention. This scheme uses piezoelectric smart composite bars as sensing elements, which have long-term stability and good durability. At the same time, by continuously optimizing the monitoring system algorithm and hardware configuration, the system can maintain stable monitoring performance for a long time, providing a strong guarantee for long-term health monitoring of structures.

[0080] In summary, this technical scheme has significant technical effects in performance indicators, not only improving the sensitivity, accuracy, and reliability of monitoring, but also enhancing the adaptability and intelligence level of the system, injecting new vitality into the development of the field of structural health monitoring.

[0081] In another embodiment, the electric signal processing module is configured to preprocess and convert the set of electric signals to obtain dynamic pressure data between the concrete and the piezoelectric smart composite reinforcement about corresponding directions, including:

[0082] After the interference noise filtering preprocessing of all the electric signals in the set of electric signals, the conversion processing is performed on all the electric signals in the set of electric signals to obtain the dynamic pressure data between the piezoelectric smart composite reinforcement and the concrete at different embedded position points in the concrete in the horizontal direction and the vertical direction. The dynamic pressure data refers to the dynamic pressure data between the piezoelectric smart composite reinforcement and the concrete at the embedded position point in the continuous time interval exceeding the preset time length threshold.

[0083] The piezoelectric patch sensor is disturbed by internal and external factors during operation, and the generated electric signals inevitably contain interference noise. In order to avoid the influence of interference noise on the analysis accuracy of the pressure state between the piezoelectric smart composite reinforcement and the concrete, the interference noise filtering preprocessing such as Kalman filtering processing is performed on all the electric signals in the set of electric signals. Based on the working principle of the piezoelectric patch sensor, the conversion processing is performed on all the electric signals in the set of electric signals to obtain the dynamic pressure data between the piezoelectric smart composite reinforcement and the concrete at different embedded position points in the concrete in the horizontal direction and the vertical direction. The dynamic pressure data refers to the dynamic pressure data between the piezoelectric smart composite reinforcement and the concrete at the embedded position point in the continuous time interval exceeding the preset time length threshold.

[0084] In another embodiment, the first analysis module is configured to perform first analysis on the dynamic pressure data to determine the contact force change characteristic information between the surface of the piezoelectric smart composite reinforcement and the concrete, including:

[0085] The dynamic pressure data between the piezoelectric smart composite reinforcement and the concrete at all embedded position points in the concrete in the horizontal direction is analyzed to determine the pressure action change characteristic information of the piezoelectric smart composite reinforcement surface stress from the concrete, which is used as the contact force change characteristic information. The pressure action change characteristic information includes the change characteristic information of the pressure action size of the piezoelectric smart composite reinforcement surface stress from the concrete with time.

[0086] The beneficial effects of the above embodiments are that the dynamic pressure data corresponding to the horizontal direction between the piezoelectric smart composite reinforcement embedded in the concrete and the concrete at the embedding position point refers to the pressure action on the surface of the piezoelectric smart composite reinforcement between the concrete at the embedding position point. By analyzing the time evolution of the dynamic pressure data corresponding to the horizontal direction, the characteristic information of the change of the pressure action on the surface of the piezoelectric smart composite reinforcement from the concrete over time is obtained, thereby long-term dynamic characterization of the pressure action of the concrete on the surface of the piezoelectric smart composite reinforcement. When the bonding performance between the concrete and the surface of the piezoelectric smart composite reinforcement deteriorates, the pressure action of the concrete on the surface of the piezoelectric smart composite reinforcement also correspondingly decreases, so the characteristic information of the change of the pressure action on the surface of the piezoelectric smart composite reinforcement from the concrete over time can accurately determine the change trend of the bonding performance between the concrete and the surface of the piezoelectric smart composite reinforcement.

[0087] In another embodiment, the second analysis module is used to perform a second analysis on the dynamic pressure data to determine the movement state characteristic information of the piezoelectric patch sensor on the surface of the fiber composite reinforcement, including:

[0088] The dynamic pressure data corresponding to the vertical direction between the piezoelectric smart composite reinforcement and the concrete at all embedding position points in the concrete is analyzed to determine the fluctuation characteristic information of the dynamic pressure data; wherein the fluctuation characteristic information of the pressure data includes interval time information of the fluctuation of the pressure value corresponding to the vertical direction between the piezoelectric smart composite reinforcement and the concrete.

[0089] Based on the fluctuation characteristic information of the dynamic pressure data, the movement displacement change characteristic information of the piezoelectric patch sensor on the surface of the fiber composite reinforcement is determined, and the movement state characteristic information is obtained.

[0090] The beneficial effects of the above embodiments are that when the bonding performance between the concrete and the surface of the piezoelectric smart composite bar is poor, the piezoelectric patch sensor on the surface of the piezoelectric smart composite bar cannot be firmly attached to the surface of the piezoelectric smart composite bar, and the aforementioned thread gap existing on the surface of the piezoelectric smart composite bar causes the concrete to be unable to fill the surface of the piezoelectric smart composite bar sufficiently tightly, resulting in a gap between the surface of the piezoelectric smart composite bar and the concrete. The piezoelectric patch sensor that cannot be firmly attached to the surface of the piezoelectric smart composite bar slowly moves downward due to the existence of the gap. Whenever the piezoelectric patch sensor moves, the frictional force and the vibrational force during the movement will interfere with the detection of the piezoelectric patch sensor, causing the electrical signal generated by the piezoelectric patch sensor to fluctuate. Correspondingly, the pressure data calculated from the electrical signal will also present the same fluctuation, and the fluctuation interval time (i.e., the time interval between the pressure data corresponding to adjacent two fluctuations) of the pressure values contained in the pressure data is related to the movement displacement change of the piezoelectric patch sensor. Therefore, the dynamic pressure data between the piezoelectric smart composite bar and the concrete at all embedded position points in the concrete in the vertical direction is analyzed to determine the fluctuation change characteristic information of the dynamic pressure data, and the fluctuation change characteristic information is processed in reverse to obtain the movement displacement change characteristic information (i.e., information such as the movement distance and the movement duration corresponding to each movement) of the piezoelectric patch sensor on the surface of the fiber composite bar, which provides reliable data basis for subsequent identification of the change of the bonding force between the concrete and the surface of the piezoelectric smart composite bar.

[0091] In another embodiment, the stress action identification module is configured to determine stress action change information between the surface of the piezoelectric smart composite bar and the concrete based on the contact force change characteristic information, including:

[0092] Based on the sensing area size of the piezoelectric patch sensor on the surface of the piezoelectric smart composite bar, the pressure change characteristic information of the piezoelectric smart composite bar surface subjected to the pressure from the concrete over time contained in the contact force change characteristic information is analyzed to determine the stress action change information between the surface of the piezoelectric smart composite bar and the concrete. The stress action change information includes the stress action change information between the surface of the piezoelectric smart composite bar and the concrete over time.

[0093] The piezoelectric patch sensor generates an electrical signal due to the pressure from the concrete on the sensing surface of the piezoelectric patch sensor, and the pressure from the concrete on the piezoelectric patch sensor is positively correlated with the stress between the concrete and the surface of the piezoelectric smart composite bar. Based on the size of the sensing area of the piezoelectric patch sensor on the surface of the piezoelectric smart composite bar, the unit area action analysis is performed on the pressure from the concrete on the surface of the piezoelectric smart composite bar contained in the contact force change characteristic information, the stress change information between the surface of the piezoelectric smart composite bar and the concrete over time is determined, and the long-term reliable identification and characterization of the stress change between the concrete and the surface of the piezoelectric smart composite bar are realized.

[0094] In another embodiment, the adsorption identification module is configured to determine, based on the movement state characteristic information, adsorption force state information of a concrete region in contact with the piezoelectric smart composite bar, including:

[0095] Based on the movement displacement change characteristic information of the piezoelectric patch sensor on the surface of the fiber composite bar contained in the movement state characteristic information, an average movement speed of the piezoelectric patch sensor moving on the surface of the piezoelectric smart composite bar is determined.

[0096] Based on the average movement speed, adsorption force state information of a concrete region in contact with the piezoelectric smart composite bar is determined; wherein the adsorption force state information includes adsorption force size distribution information of the concrete region in contact with the piezoelectric smart composite bar along the length direction of the piezoelectric smart composite bar.

[0097] The piezoelectric patch sensor generates an electrical signal due to the pressure from the concrete on the sensing surface of the piezoelectric patch sensor, and the pressure from the concrete on the piezoelectric patch sensor is positively correlated with the stress between the concrete and the surface of the piezoelectric smart composite bar. Based on the size of the sensing area of the piezoelectric patch sensor on the surface of the piezoelectric smart composite bar, the unit area action analysis is performed on the pressure from the concrete on the surface of the piezoelectric smart composite bar contained in the contact force change characteristic information, the stress change information between the surface of the piezoelectric smart composite bar and the concrete over time is determined, and the long-term reliable identification and characterization of the stress change between the concrete and the surface of the piezoelectric smart composite bar are realized.

[0098] In another embodiment, the abnormal region determination module is configured to determine, based on the stress change information and the adsorption force state information, a region in which the bonding performance between the concrete and the piezoelectric smart composite bar is deteriorated, including:

[0099] Based on the stress change information and the adsorption force state information, it is determined whether the position point of the embedded piezoelectric smart composite bar in the concrete is in a state of weakened adhesion between the concrete and the surface of the piezoelectric smart composite bar.

[0100] Based on all the position points in the state of weakened adhesion in the concrete, a region of deteriorated adhesion between the concrete and the piezoelectric smart composite bar is determined.

[0101] The above-mentioned embodiments have the beneficial effect that, based on the stress change information and the adsorption force state information, the change in the adhesion between the concrete and the surface of the piezoelectric smart composite bar corresponding to the position point of the embedded piezoelectric smart composite bar in the concrete is determined; if the stress change information indicates that the stress between the concrete and the surface of the piezoelectric smart composite bar is becoming smaller and / or the adsorption force state information indicates that the adsorption force of the concrete region in contact with the piezoelectric smart composite bar is becoming smaller, it is determined that the position point is in a state of weakened adhesion between the concrete and the surface of the piezoelectric smart composite bar. Furthermore, the region surrounded by all the position points in the state of weakened adhesion in the concrete is determined as the region of deteriorated adhesion between the concrete and the piezoelectric smart composite bar, thereby realizing accurate positioning of the region of deteriorated adhesion.

[0102] In general, the piezoelectric smart composite bar and the long-term adhesion performance monitoring system for concrete distinguish and analyze the electrical signals of all piezoelectric smart composite bars embedded in the concrete, obtain dynamic pressure data between the concrete and the piezoelectric smart composite bar in the corresponding direction, and perform multi-dimensional identification of the pressure action between the concrete and the piezoelectric smart composite bar; the contact force change characteristic information between the surface of the piezoelectric smart composite bar and the concrete and the movement state characteristic information of the piezoelectric patch sensor on the surface of the fiber composite bar are obtained from the dynamic pressure data analysis, so as to determine the stress change information between the surface of the piezoelectric smart composite bar and the concrete and the adsorption force state information of the concrete region in contact with the piezoelectric smart composite bar, thereby determining the region of deteriorated adhesion between the concrete and the piezoelectric smart composite bar. The piezoelectric detection is used for long-term and continuous stress monitoring of the direct contact action between the concrete and the piezoelectric smart composite bar, and the relative displacement state between the piezoelectric patch sensor and the fiber composite bar is used for identifying the adsorption force of the concrete, so as to monitor and identify the adhesion performance between the composite bar and the concrete from multiple aspects, and realize accurate positioning of the region of deteriorated adhesion.

[0103] The above is only one specific embodiment of the present application, and any improvement made on the basis of the concept of the present application is considered to be within the protection scope of the present application.

Claims

1. A long-term bond performance monitoring system for piezoelectric smart composite rebar and concrete, characterized by, The system comprises: an electric signal acquisition module, configured to collect electric signals from different piezoelectric smart composite bars based on spatial distribution information of all piezoelectric smart composite bars embedded in the concrete, to obtain a plurality of electric signal sets corresponding to different directions; wherein the piezoelectric smart composite bar comprises a fiber composite bar and a plurality of piezoelectric patch sensors discretely distributed on the surface of the fiber composite bar; an electric signal processing module, configured to pre-process and convert the electric signal sets, to obtain dynamic pressure data between the concrete and the piezoelectric smart composite bars about the corresponding direction; a first analysis module, configured to perform first analysis on the dynamic pressure data, to determine contact force change characteristic information between the surface of the piezoelectric smart composite bar and the concrete; a second analysis module, configured to perform second analysis on the dynamic pressure data, to determine movement state characteristic information of the piezoelectric patch sensors on the surface of the fiber composite bar; a stress action recognition module, configured to determine stress action change information between the surface of the piezoelectric smart composite bar and the concrete based on the contact force change characteristic information; an adsorption action recognition module, configured to determine adsorption force state information of a concrete region in contact with the piezoelectric smart composite bar based on the movement state characteristic information; an abnormal region determination module, configured to determine a region with deteriorated bonding performance between the concrete and the piezoelectric smart composite bar based on the stress action change information and the adsorption force state information.

2. The piezoelectric smart composite bar and concrete long-term bonding performance monitoring system of claim 1, wherein: the electric signal acquisition module is configured to collect electric signals from different piezoelectric smart composite bars based on spatial distribution information of all piezoelectric smart composite bars embedded in the concrete, to obtain a plurality of electric signal sets corresponding to different directions, comprising: obtaining embedding position information and orientation attitude information of all piezoelectric smart composite bars embedded in the concrete, dividing the interior of the concrete into a plurality of first composite bar distribution regions and a plurality of second composite bar distribution regions based on the embedding position information; wherein the distribution density of piezoelectric smart composite bars in the first composite bar distribution region is greater than that in the second composite bar distribution region; collecting electric signals generated by piezoelectric smart composite bars in the first composite bar distribution region and the second composite bar distribution region with different signal acquisition sensitivities; based on the orientation attitude information, all collected electric signals are distinguished and integrated to obtain first and second electric signal sets corresponding to horizontal and vertical orientation attitudes.

3. The piezoelectric smart composite bar and concrete long-term bond performance monitoring system of claim 1, wherein: The piezoelectric smart composite bar and concrete long-term bonding performance monitoring system further comprises: extracting the area of the first composite bar distribution region; extracting the area of the second composite bar distribution region; extracting the number of electric signals generated by piezoelectric smart composite bars in the first composite bar distribution region; extracting the number of electric signals generated by piezoelectric smart composite bars in the second composite bar distribution region; The signal acquisition sensitivity corresponding to the first composite tendon distribution area is obtained by using the area of the region corresponding to the first composite tendon distribution area and the number of electric signals generated by the piezoelectric intelligent composite tendons under the first composite tendon distribution area. The signal acquisition sensitivity corresponding to the first composite tendon distribution area is obtained by using the area of the region corresponding to the first composite tendon distribution area and the number of electric signals generated by the piezoelectric intelligent composite tendons under the first composite tendon distribution area. wherein, L 01 represents the signal acquisition sensitivity corresponding to the first composite bar distribution area; L c represents the preset initial value of the sensitivity; S 01 represents the area of the first composite bar distribution area; S 02 represents the area of the second composite bar distribution area; n represents the number of electric signals generated by the piezoelectric intelligent composite bars under the first composite bar distribution area; and m represents the number of electric signals generated by the piezoelectric intelligent composite bars under the second composite bar distribution area. The signal acquisition sensitivity corresponding to the second composite tendon distribution area is obtained by using the area of the region corresponding to the second composite tendon distribution area and the number of electric signals generated by the piezoelectric intelligent composite tendons under the second composite tendon distribution area. The signal acquisition sensitivity corresponding to the second composite tendon distribution area is obtained by using the area of the region corresponding to the second composite tendon distribution area and the number of electric signals generated by the piezoelectric intelligent composite tendons under the second composite tendon distribution area. wherein, L 02 represents the signal acquisition sensitivity corresponding to the second composite reinforcement distribution area; L c represents the preset initial value of the sensitivity; S 01 represents the area of the first composite reinforcement distribution area; S 02 represents the area of the second composite reinforcement distribution area; n represents the number of electric signals generated by the piezoelectric intelligent composite reinforcement under the first composite reinforcement distribution area; and m represents the number of electric signals generated by the piezoelectric intelligent composite reinforcement under the second composite reinforcement distribution area.

4. The piezoelectric intelligent composite tendon and concrete long-term bonding performance monitoring system of claim 1, wherein: The electric signal processing module is configured to pre-process and convert the set of electric signals to obtain dynamic pressure data between the concrete and the piezoelectric intelligent composite tendons inside the concrete with respect to corresponding directions, including: After pre-processing all electric signals under the set of electric signals by interference noise filtering, the set of electric signals is converted to obtain dynamic pressure data between the piezoelectric intelligent composite tendons at different embedded position points inside the concrete and the concrete in horizontal and vertical directions; wherein the dynamic pressure data refers to dynamic pressure data between the piezoelectric intelligent composite tendons at the embedded position points and the concrete in a continuous time interval exceeding a preset time length threshold.

5. The piezoelectric intelligent composite tendon and concrete long-term bonding performance monitoring system of claim 1, wherein: The first analysis module is configured to perform first analysis on the dynamic pressure data to determine contact force change characteristic information between the surface of the piezoelectric intelligent composite tendon and the concrete, including: The dynamic pressure data between the piezoelectric intelligent composite tendons at all embedded position points inside the concrete and the concrete in the horizontal direction is analyzed to determine pressure change characteristic information of the piezoelectric intelligent composite tendon surface stress from the concrete, which is used as the contact force change characteristic information; wherein the pressure change characteristic information includes pressure change characteristic information of the piezoelectric intelligent composite tendon surface stress from the concrete over time.

6. The piezoelectric intelligent composite tendon and concrete long-term bonding performance monitoring system of claim 1, wherein: The second analysis module is configured to perform second analysis on the dynamic pressure data to determine movement state characteristic information of the piezoelectric patch sensor on the surface of the fiber composite tendon, including: The dynamic pressure data between the piezoelectric intelligent composite tendons at all embedded position points inside the concrete and the concrete in the vertical direction is analyzed to determine fluctuation change characteristic information of the dynamic pressure data; wherein the fluctuation change characteristic information of the pressure data includes interval time information of fluctuation of the pressure value of the piezoelectric intelligent composite tendon and the concrete in the vertical direction. Based on the fluctuation change feature information of the dynamic pressure data, the moving displacement change feature information of the piezoelectric patch sensor on the surface of the fiber composite tendon is determined, and the moving state feature information is determined accordingly. 7.The piezoelectric smart composite tendon and concrete long-term bonding performance monitoring system of claim 1, wherein: The stress action recognition module is configured to determine the stress action change information between the surface of the piezoelectric smart composite tendon and the concrete based on the contact force change feature information, including: Based on the sensing area size of the piezoelectric patch sensor on the surface of the piezoelectric smart composite tendon, the stress action change information between the surface of the piezoelectric smart composite tendon and the concrete is determined by analyzing the pressure action size change feature information of the surface of the piezoelectric smart composite tendon from the concrete over time contained in the contact force change feature information; wherein the stress action change information includes the stress action size change information between the surface of the piezoelectric smart composite tendon and the concrete over time. 8.The piezoelectric smart composite tendon and concrete long-term bonding performance monitoring system of claim 1, wherein: The adsorption action recognition module is configured to determine the adsorption force state information of the concrete region in contact with the piezoelectric smart composite tendon based on the moving state feature information, including: Based on the moving displacement change feature information of the piezoelectric patch sensor on the surface of the fiber composite tendon contained in the moving state feature information, the average moving speed of the piezoelectric patch sensor on the surface of the piezoelectric smart composite tendon that moves is determined; Based on the average moving speed, the adsorption force state information of the concrete region in contact with the piezoelectric smart composite tendon is determined; wherein the adsorption force state information includes the adsorption force size distribution information of the concrete region in contact with the piezoelectric smart composite tendon along the length direction of the piezoelectric smart composite tendon. 9.The piezoelectric smart composite tendon and concrete long-term bonding performance monitoring system of claim 1, wherein: The abnormal region determination module is configured to determine the region of the piezoelectric smart composite tendon and the concrete inside the concrete whose bonding performance deteriorates based on the stress action change information and the adsorption force state information, including: Based on the stress action change information and the adsorption force state information, it is judged whether the position point of the piezoelectric smart composite tendon buried in the concrete inside the concrete is in a bonding force weakening state between the concrete and the surface of the piezoelectric smart composite tendon; Based on all position points of the concrete inside in the bonding force weakening state, the region of the piezoelectric smart composite tendon and the concrete inside the concrete whose bonding performance deteriorates is determined.

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