High-pressure-resistant bidirectional flexural piezoelectric intelligent aggregate embedded in cement-based structure

Abstract

This invention belongs to the technical field of embedded piezoelectric sensor devices and cement-based functional composite materials, specifically relating to a cement-based embedded high-pressure resistant bidirectional bending-tension piezoelectric smart aggregate. The smart aggregate includes: a shell assembly comprising a first shell and a second shell that snap together to form a sealed cavity; both the first and second shells include a force-radiating structure, a vibration-conducting structure, and a force-transmitting component connecting them; two piezoelectric driving elements symmetrically arranged on the inner surfaces of the vibration-conducting structures of the first and second shells; a circuit board disposed within the sealed cavity; an elastic electrical connection structure abutting the circuit board against the electrodes of the piezoelectric driving elements; and a grounding structure that suspends and fixes the circuit board within the sealed cavity, forming a grounding loop. This invention utilizes an arc-shaped dome to achieve high-pressure to pre-tightening force conversion, dual piezoelectric driving elements to optimize low-frequency sound radiation, and a weld-free elastic connection and suspended grounding structure for vibration and impact resistance, making it suitable for structural health monitoring in deep underwater high-pressure conditions.

Description

Technical Field

[0001] This invention relates to the field of embedded piezoelectric sensor devices and cement-based functional composite materials, specifically to a cement-based embedded high-pressure resistant bidirectional bending tension piezoelectric smart aggregate, which belongs to the cross-application field of smart piezoelectric composite materials and high-end equipment health monitoring. Background Technology

[0002] During the construction and operation and maintenance of large-scale infrastructure projects such as water conservancy dams, long-term real-time monitoring of internal damage (such as cracks and voids) and stress state of concrete structures is a key aspect of ensuring the safety and stability of engineering structures and extending their service life. Smart aggregates based on piezoelectric ceramics (PZT), due to their active sensing and actuation capabilities, can be embedded as an important monitoring method for the health monitoring of concrete structures.

[0003] However, existing smart aggregate technologies face severe technical challenges when applied to high-pressure scenarios such as the bottom of deep-water dams, where environmental pressure exceeds 1 MPa. Firstly, their pressure resistance is insufficient. Traditional smart aggregate technologies often employ a simple method of directly encapsulating PZT patches within cement or marble blocks. Under the immense pressure exerted during concrete pouring and in long-term humid environments, the PZT components are prone to breakage or drift in characteristic parameters due to pressure overload, ultimately losing their core monitoring functions. Secondly, their electromechanical conversion efficiency is low. Traditional encapsulation structures significantly dampen PZT vibrations, and vibration modes are often limited to simple radial or thickness vibrations, restricting the transmission distance of sound waves in the concrete medium and failing to meet the long-distance monitoring requirements of large structures. Thirdly, their reliability is poor and the installation process is complex. In traditional designs, PZTs are often connected to circuit board components via wire soldering, increasing manufacturing complexity and increasing the risk of sensor failure due to fatigue fracture of solder joints during high-frequency vibrations during concrete pouring and long-term service, severely impacting the long-term stability of the monitoring system.

[0004] Therefore, there is an urgent need to develop a new type of intelligent aggregate that can enhance its own structure using a high-pressure environment, has displacement amplification function, and has highly reliable internal connections. Summary of the Invention

[0005] The purpose of this invention is to provide a cement-based embedded high-pressure resistant bidirectional bending piezoelectric smart aggregate to solve the problems of poor pressure resistance, low sound wave transmission efficiency, and insufficient reliability of internal welding connections in existing smart aggregates under deep-water high-pressure environments.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A cement-based embedded high-pressure resistant biaxial bending-tension piezoelectric smart aggregate, comprising: The housing assembly includes a first housing and a second housing that are fastened together to form a sealed cavity. Both the first housing and the second housing include a force-radiating structure for bearing pressure and radiating sound waves outward, a vibration-conducting structure for transmitting vibrations, and a force-transmitting component connecting the force-radiating structure and the vibration-conducting structure. The force-radiating structure is an outwardly convex arc-shaped dome. Two piezoelectric drive elements are respectively attached to the inner surfaces of the vibration transmission structures of the first housing and the second housing. The two piezoelectric drive elements are arranged symmetrically about the geometric center of the sealed cavity and are configured to perform in-phase extension and contraction vibration. The force is transmitted to the two force-radiating structures of the housing assembly through the force transmission component to generate overall bending and tension vibration. A circuit board is disposed within the sealed cavity, and a functional circuit module is integrated on the circuit board. The functional circuit module is configured to perform at least one function among sensing, data processing, communication, or energy management. The functional circuit module is electrically connected to the piezoelectric drive element through a flexible electrical connection structure. One end of the elastic electrical connection structure is connected to the circuit board, and the other end elastically abuts against the electrode of the piezoelectric drive element, thereby realizing non-welding electrical conduction between the circuit board and the piezoelectric drive element; The grounding structure includes a crimping portion disposed on the inner wall of the first housing and the second housing, and a conductive buffer member sandwiched between the circuit board and the crimping portion; when the first housing and the second housing are fastened together, the conductive buffer member is compressed, suspending and fixing the circuit board in the sealed cavity and forming a grounding circuit for the circuit board.

[0007] Furthermore, the outer surface of the arc-shaped dome has a smooth, streamlined shape; the vibration transmission structure is a planar vibrating plate, and the force transmission component is a force transmission column connecting the center of the vibrating plate to the apex of the arc-shaped dome; the edge of the vibrating plate is rigidly connected to or integrally formed with the inner wall of the arc-shaped dome.

[0008] Furthermore, the piezoelectric driving element is a piezoelectric ceramic sheet, a piezoelectric composite material, or a piezoelectric single crystal wafer; the piezoelectric driving element and the vibration transmission structure are fixedly connected by a conductive adhesive layer.

[0009] Furthermore, the conductive buffer is one of conductive foam, conductive rubber, or metal elastic sheet; the edge of the circuit board is provided with an exposed grounded conductive area, and the conductive buffer is sandwiched between the grounded conductive area and the pressing part.

[0010] Furthermore, the elastic electrical connection structure includes a spring pin, an elastic conductive probe, or a metal spring; the surface of the elastic electrical connection structure is provided with a conductive plating layer; the extension and retraction direction of the elastic electrical connection structure is perpendicular to the plane of the circuit board and is located in the central region of the circuit board.

[0011] Furthermore, the first housing and the second housing have complementary positioning stop structures at their snap-fit ​​edges, and a sealing element is provided in the fitting gap of the positioning stop structure, and a sealing connection layer is provided at the external seam of the housing assembly.

[0012] Furthermore, the positioning stop structure is an embedded fit between a boss and a groove; the sealing element is a structural adhesive, a sealing gasket, or a sealing ring; and the sealing connection layer is a laser welding layer, an ultrasonic welding layer, or an adhesive layer.

[0013] Furthermore, the circuit board also integrates an impedance modulation circuit, which is configured to modulate the reflection characteristics of the incident sound wave by changing the electrical load state of the piezoelectric drive element to achieve communication.

[0014] Furthermore, the working resonance frequency of the smart aggregate is functionally related to the curvature of the force-radiating structure, the wall thickness of the shell assembly, and the size of the force-transmitting component; by configuring the ratio of the thickness of the vibration transmission structure to the diameter of the piezoelectric driving element, the smart aggregate can generate overall bending-tension resonance in a preset low-frequency band.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention utilizes the arch effect of the dome to convert external high pressure into pre-tightening force within the shell, significantly improving pressure resistance and protecting core components. Symmetrical drive from dual piezoelectric drive elements creates breathing mode vibration, which, combined with the displacement amplification effect of the force transmission column, greatly increases the low-frequency sound wave radiation power and transmission distance. A weldless connection structure using elastic electrical connections and conductive buffers, combined with a multi-level sealing design, avoids connection failures caused by vibration, ensuring device reliability. The circuit board integrates impedance modulation circuitry to achieve acoustic backscatter communication, and with an adjustable resonant frequency design, achieves acoustic impedance matching with the concrete medium, fully meeting the long-term real-time monitoring needs of internal damage and stress state of concrete structures under high-pressure environments such as deep-water dams. Attached Figure Description

[0016] Figure 1 This is an overall structural diagram of the intelligent aggregate of the present invention; Figure 2 This is an internal cross-sectional view of the intelligent aggregate of the present invention; Figure 3 This is a partial structural diagram of the intelligent aggregate of the present invention.

[0017] The markings in the figure are: 1. First shell; 101. First arc-shaped dome; 2. Second shell; 201. Second arc-shaped dome; 3. Vibrating plate; 4. Force transmission column; 5. Pressing part; 6. Piezoelectric drive element; 7. Circuit board; 8. Conductive buffer; 9. Elastic electrical connection structure; 10. Conductive adhesive layer. Detailed Implementation

[0018] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to provide the reader with a more thorough and complete understanding.

[0019] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0021] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a cement-based embedded high-pressure resistant bidirectional bending piezoelectric smart aggregate of the present invention, so that those skilled in the art can understand it.

[0022] This embodiment provides a cement-based embedded high-pressure resistant bidirectional bending piezoelectric smart aggregate, including a shell assembly, two piezoelectric driving elements 6, a circuit board 7, and a grounding structure. The shell assembly is the load-bearing and vibration radiation matrix of the entire smart aggregate, including a first shell 1 and a second shell 2 that are fastened together to form a sealed cavity. The first shell and the second shell are symmetrical in structure. Both the first shell 1 and the second shell 2 include a force-receiving radiation structure for bearing pressure and radiating sound waves outward, a vibration transmission structure for transmitting vibration, and a force-transmitting component connecting the force-receiving radiation structure and the vibration transmission structure. The force-receiving radiation structure is an outwardly convex arc-shaped dome. Two piezoelectric drive elements 6 are respectively attached to the inner surfaces of the vibration transmission structure of the first housing 1 and the second housing 2, and are used to generate vibration and drive the force-radiating structure to move through the force transmission component; the circuit board 7 is located in the sealed cavity, and the circuit board 7 integrates a functional circuit module, which is configured to perform at least one function of sensing, data processing, communication or energy management, and is electrically connected to the piezoelectric drive elements 6 through the elastic electrical connection structure 9.

[0023] The functional circuit module also integrates an energy storage unit, a microcontroller unit, and auxiliary sensors, including at least one of a temperature sensor, an acceleration sensor, or a stress sensor.

[0024] The flexible electrical connection structure is assembled using a non-welded connection method. One end is fixedly connected to the circuit board surface, while the other end always elastically abuts against the electrode surface of the piezoelectric drive element. Relying on its own elastic expansion and contraction characteristics, it maintains continuous close contact with the electrode of the piezoelectric drive element. The non-welded electrical conduction structure in this embodiment can effectively avoid damage to the performance of the piezoelectric drive element caused by the high temperature of welding. At the same time, it can adapt to the contact stability under pressure deformation of the housing, component assembly errors, and long-term vibration conditions of the equipment, ensuring continuous and reliable electrical connection.

[0025] The grounding structure is used to fix the circuit board 7 in a sealed cavity and to achieve the grounding connection of the circuit board 7. The grounding structure includes a crimping part 5 disposed on the inner wall of the first housing 1 and the second housing 2, and a conductive buffer 8 sandwiched between the circuit board 7 and the crimping part 5; when the first housing 1 and the second housing 2 are fastened together, the conductive buffer 8 is compressed, thereby achieving the suspension and fixation of the circuit board 7 and the conduction of the grounding circuit.

[0026] In this embodiment, when the housings are fastened together, the pressing portion 5 on the inner wall of the first housing 1 and the second housing 2 applies pre-pressure to the conductive buffer 8, compressing it. The elastic force of the conductive buffer 8 reacts to the circuit board 7, suspending and clamping the circuit board 7 between the two housings, thus avoiding direct rigid contact between the circuit board 7 and the housings. This suspension and fixing method can absorb the impact energy generated by concrete pouring and vibration and structural vibration, protecting the precision components on the circuit board 7. It can also achieve a conductive connection between the circuit board 7 and the housing through the conductive buffer 8, forming a complete grounding loop, effectively shielding external electromagnetic interference, and improving the stability and reliability of the circuit operation.

[0027] In this embodiment, after the intelligent aggregate is embedded in the concrete structure of the deep-water dam, the functional circuit module outputs a driving electrical signal to the piezoelectric drive element 6 through the electrical connection structure. The expansion and contraction vibration generated by the piezoelectric drive element 6 after being energized is accurately transmitted to the force-radiating structures at both ends through the corresponding force transmission components, driving the upper and lower sets of arc-shaped dome-shaped force-radiating structures to deform synchronously, so that the entire shell assembly generates stable overall bidirectional bending and tension vibration. When the sound wave propagates inside the concrete, if it encounters damage such as cracks or voids, it will be reflected, scattered or attenuated. The reflected sound wave signal is received by the piezoelectric drive element 6, which converts the mechanical vibration into an electrical signal and feeds it back to the functional circuit module. After processing the signal, the functional circuit module completes the monitoring of the health status of the dam structure. Throughout the process, the grounding structure ensures that the circuit board 7 is stably fixed in the sealed cavity, and at the same time achieves reliable grounding, ensuring the stability of the circuit operation.

[0028] The aforementioned cement-based embedded high-pressure resistant bidirectional bending piezoelectric smart aggregate adopts a symmetrical bidirectional bending vibration structure, combined with an outwardly convex arc-shaped dome load-bearing structure, which significantly improves the high-pressure resistance of the smart aggregate. It can adapt to the complex working conditions of cement-based structure casting and long-term pressure bearing, and is not prone to structural deformation, failure and failure. Through the in-phase symmetrical vibration design of dual piezoelectric drive elements, the shell can achieve bidirectional bending vibration of the whole, with a wider sound wave radiation range, higher vibration sensing sensitivity, and better structural monitoring and sound wave communication. The use of elastic electrical connection structure 9 realizes non-welded electrical conduction, avoids welding process defects, and improves electrical connection reliability and equipment service life. Relying on conductive buffer components, the circuit board 7 is suspended and fixed in an integrated grounding design, which not only achieves efficient electromagnetic shielding and electrostatic protection, but also buffers external mechanical impact and protects the internal circuit structure. The overall sealed cavity design can effectively isolate cement slurry, water vapor and impurities from intrusion, adapting to embedded pre-embedded working scenarios, and significantly improving the overall stability and durability of the equipment.

[0029] In some embodiments, the outer surface of the arc-shaped dome of the force-radiating structure is smooth and streamlined, the vibration transmission structure is a planar vibrating plate 3, and the force transmission component is a force transmission column 4 connecting the center of the vibrating plate 3 and the apex of the arc-shaped dome; the edge of the vibrating plate 3 is rigidly connected to the inner wall of the arc-shaped dome or integrally formed.

[0030] In this embodiment, the convex structure of the arc-shaped dome utilizes the "arch effect" to convert external deep-water pressure into compressive stress within the shell. This not only prevents damage from high pressure but also generates beneficial pre-tightening force, enhancing overall pressure resistance. The smooth, streamlined outer surface of the arc-shaped dome reduces voids around the aggregate and disperses external stress during concrete pouring. The planar vibrating plate 3 can fully fit with the piezoelectric drive element 6, ensuring the integrity of vibration reception and transmission. The force transmission column 4 connects the center of the vibrating plate 3 to the apex of the arc-shaped dome, transmitting the minute vibrations of the vibrating plate 3 to the arc-shaped dome without loss, thus amplifying the vibration displacement. The rigid connection or integral molding design between the vibrating plate 3 and the arc-shaped dome forms a closed mechanical transmission chain, preventing energy loss or structural loosening during vibration, further improving sound radiation efficiency and structural stability.

[0031] In some embodiments, the piezoelectric driving element is a piezoelectric ceramic sheet, a piezoelectric composite material, or a piezoelectric single crystal wafer; the piezoelectric driving element is fixedly connected to the vibration transmission structure through a conductive adhesive layer 10.

[0032] In this embodiment, the piezoelectric drive element 6 is selected, which utilizes the inverse piezoelectric effect to convert electrical energy into mechanical energy to generate vibration, and simultaneously utilizes the direct piezoelectric effect to convert the received mechanical vibration into electrical energy. The piezoelectric drive element is attached to the inner surface of the vibration transmission structure, allowing direct vibration transmission with the structure and reducing energy loss. Different types of piezoelectric drive elements, such as piezoelectric ceramic sheets, piezoelectric composite materials, or piezoelectric single crystal wafers, can be selected to adapt to the performance requirements of different monitoring scenarios. In this embodiment, PZT-5A, PZT-4, or PZT-5H piezoelectric ceramic discs are preferred, and their diameter is smaller than that of the vibration plate 3. The conductive adhesive layer 10 not only securely fixes the piezoelectric drive element to the vibration transmission structure but also ensures the conductive connection between the two, providing a foundation for the formation of the electrical circuit and preventing the piezoelectric drive element from detaching or making poor contact under vibration or high-pressure environments.

[0033] In some embodiments, the conductive buffer 8 is one of conductive foam, conductive rubber or metal elastic sheet; the edge of the circuit board 7 is provided with an exposed grounded conductive area, and the conductive buffer 8 is sandwiched between the grounded conductive area and the crimping part 5.

[0034] In this embodiment, conductive foam, conductive rubber, or metal elastic sheet all possess good conductivity and elasticity. When used as conductive buffer 8, they can both meet the conductivity requirements of the grounding circuit and achieve buffering and fixing of the circuit board 7 through their own elasticity. The exposed grounding conductive area at the edge of the circuit board 7 is precisely aligned with the conductive buffer 8, ensuring the conductive contact area between the conductive buffer 8 and the circuit board 7 and reducing contact resistance. The conductive buffer 8 is sandwiched between the grounding conductive area and the crimping part 5, forming a stable conductive path from the crimping part 5 to the conductive buffer 8 to the grounding conductive area, further ensuring the grounding effect and preventing the grounding connection from failing due to vibration, compression, or other factors.

[0035] In some embodiments, the elastic electrical connection structure 9 includes a spring pin, an elastic conductive probe, or a metal spring. One end of the elastic electrical connection structure 9 is connected to the circuit board 7, and the other end elastically abuts against the electrode of the piezoelectric drive element 6 to achieve solderless electrical conduction. The surface of the elastic electrical connection structure 9 is provided with a conductive plating layer. The extension and retraction direction of the elastic electrical connection structure 9 is perpendicular to the plane of the circuit board 7 and is located in the central region of the circuit board 7.

[0036] In this embodiment, the electrical connection structure employs a spring-loaded pin, elastic conductive probe, or metal spring sheet, etc., to achieve electrical conductivity between the circuit board 7 and the piezoelectric drive element 6 without welding. This avoids the fatigue fracture problem of traditional welded connections under vibration, significantly improving connection reliability. In this embodiment, the preferred electrical connection structure is a gold-plated spring-loaded pin. The conductive plating on the surface of the elastic electrical connection structure 9 reduces contact resistance and signal transmission loss. Its extension direction is perpendicular to the plane of the circuit board 7 and located in the central region, ensuring precise docking between the elastic electrical connection structure 9 and the electrodes of the piezoelectric drive element 6. Simultaneously, during vibration, it absorbs displacement deviations through its own elastic extension and contraction, maintaining stable electrical contact and ensuring smooth transmission of drive and feedback signals.

[0037] In some embodiments, the snap-fit ​​edges of the first housing 1 and the second housing 2 are provided with complementary positioning stop structures, the fitting gap of the positioning stop structures is provided with a seal, and the outer seam of the housing assembly is provided with a sealing connection layer.

[0038] In this embodiment, the first housing 1 and the second housing 2 achieve precise engagement through complementary positioning stop structures, avoiding misalignment during engagement and ensuring the assembly accuracy of the housing components. The positioning stop structure, in conjunction with the sealing element within the gap, prevents impurities such as concrete slurry and moisture from entering the sealed cavity, achieving initial sealing. The sealing connection layer at the external joints of the housing components further enhances the sealing effect, forming a double sealing protection, ensuring a dry and clean environment inside the sealed cavity, and preventing components such as the circuit board 7 and piezoelectric drive element 6 from failing due to moisture or contamination, thus adapting to the humid long-term service environment of deep-water dams.

[0039] In some embodiments, the positioning stop structure is an embedded fit between a boss and a groove; the sealing element is a structural adhesive, a gasket, or a sealing ring; and the sealing connection layer is a laser welding layer, an ultrasonic welding layer, or an adhesive layer.

[0040] In this embodiment, the embedded positioning stop structure of the boss and the groove can increase the contact area between the two shells, improve the structural stability after fastening, and provide a stable installation space for the seal. In this embodiment, the edge of the first arc-shaped dome 101 of the first shell 1 is provided with a male boss; the edge of the first arc-shaped dome 101 of the first shell 1 is provided with a male boss, and the edge of the second arc-shaped dome 201 of the second shell 2 is provided with a female groove. The two form an embedded stop structure to achieve automatic concentric positioning. In addition, after the boss and the groove are fastened, there will be a 0.15-0.2mm fit gap for placing the seal. Structural adhesive, sealing gasket or sealing ring all have good sealing performance, and the appropriate type of seal can be selected according to the actual working conditions. The sealing connection layer formed by laser welding layer, ultrasonic welding layer or adhesive layer can achieve permanent sealing connection between the two shells, with high sealing reliability and is not prone to sealing failure due to vibration, pressure change or other factors, ensuring the long-term stability of the sealing performance of the shell assembly.

[0041] In some embodiments, the circuit board 7 also integrates an impedance modulation circuit, which is configured to modulate the reflection characteristics of the incident sound wave to achieve communication by changing the electrical load state of the piezoelectric drive element 6.

[0042] In this embodiment, when the impedance modulation circuit is working, the acoustic reflection characteristics of the piezoelectric driving element 6 change accordingly by altering its electrical load state. An external receiving device emits detection acoustic waves towards the smart aggregate. After reflection by the piezoelectric driving element 6, the characteristics of the reflected acoustic waves are modulated according to the different load states. By analyzing the modulated reflected acoustic waves, the external receiving device can obtain the data information transmitted by the smart aggregate. This acoustic backscattering communication method eliminates the need for a dedicated communication module, simplifying the structural design and avoiding the difficulties of wired communication wiring. It is suitable for embedded installation scenarios of smart aggregates, enabling wireless transmission of monitoring data.

[0043] In some embodiments, the working resonant frequency of the smart aggregate is a function of the curvature of the force-radiating structure, the wall thickness of the shell assembly, and the size of the force-transmitting component; by configuring the ratio of the thickness of the vibration transmission structure to the diameter of the piezoelectric drive element 6, the smart aggregate generates overall bending-tension resonance in a preset low-frequency band.

[0044] In this embodiment, the working frequency band of the smart aggregate is 1kHz-100kHz, and the ratio of the thickness of the vibration transmission structure to the diameter of the piezoelectric drive element 6 of the elastic electrical connection structure is set to 0.02-0.08. Through the above ratio configuration, the equivalent mechanical impedance of the smart aggregate of the elastic electrical connection structure is matched with the external concrete medium, and an overall bending resonance is generated in the preset low frequency band.

[0045] In this embodiment, the 1kHz-100kHz operating frequency band is adapted to the acoustic characteristics of the concrete medium, which can reduce the propagation attenuation of sound waves in the concrete and increase the transmission distance. By adjusting the curvature of the force-radiating structure, the wall thickness of the shell assembly, and the size of the force-transmitting components, the operating resonant frequency of the smart aggregate can be precisely controlled. At the same time, by reasonably configuring the thickness of the vibration transmission structure and the diameter ratio of the driving element, the smart aggregate can generate overall bending and tension resonance in the preset low-frequency band. At this time, the sound wave radiation power is maximized, which can achieve optimal acoustic impedance matching with the concrete medium, reduce reflection loss, and further improve sound radiation efficiency and monitoring range.

[0046] The above embodiments merely illustrate several implementations of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the disclosed patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these are all implicitly contained within the present invention.

Claims

1. A cement-based structural embedded high-voltage resistant bidirectional flexoelectric piezoelectric smart aggregate, characterized in that, include: The housing assembly includes a first housing (1) and a second housing (2) that are fastened together to form a sealed cavity. Both the first housing (1) and the second housing (2) include a force-radiating structure for bearing pressure and radiating sound waves outward, a vibration-conducting structure for transmitting vibrations, and a force-transmitting component connecting the force-radiating structure and the vibration-conducting structure. The force-radiating structure is an outwardly convex arc-shaped dome. The outer surface of the arc-shaped dome is smooth and streamlined. The vibration-conducting structure is a planar vibrating plate (3). The force-transmitting component is a force-transmitting column (4) connecting the center of the vibrating plate (3) and the apex of the arc-shaped dome. The edge of the vibrating plate (3) is rigidly connected to or integrally formed with the inner wall of the arc-shaped dome. Two piezoelectric drive elements (6) are respectively attached to the inner surfaces of the vibration transmission structures of the first housing (1) and the second housing (2). The two piezoelectric drive elements (6) are arranged symmetrically about the geometric center of the sealed cavity and are configured to perform in-phase extension and contraction vibration. They are transmitted to the two force-radiating structures of the housing assembly through the force transmission component to generate overall bending and tension vibration. A circuit board (7) is disposed in the sealed cavity. A functional circuit module is integrated on the circuit board (7). The functional circuit module is configured to perform at least one function among sensing, data processing, communication or energy management. The functional circuit module is electrically connected to the piezoelectric drive element (6) through a flexible electrical connection structure (9). One end of the elastic electrical connection structure (9) is connected to the circuit board (7), and the other end is elastically abutted against the electrode of the piezoelectric drive element (6), thereby realizing non-welded electrical conduction between the circuit board (7) and the piezoelectric drive element (6); The grounding structure includes a crimping part (5) disposed on the inner wall of the first housing (1) and the second housing (2), and a conductive buffer (8) sandwiched between the circuit board (7) and the crimping part (5); when the first housing (1) and the second housing (2) are fastened together, the conductive buffer (8) is compressed, suspending and fixing the circuit board (7) in the sealed cavity and forming a grounding circuit for the circuit board (7); The circuit board (7) also integrates an impedance modulation circuit, which is configured to modulate the reflection characteristics of the incident sound wave by changing the electrical load state of the piezoelectric drive element (6) to achieve communication.

2. A cement-based structural embedded high voltage resistant bidirectional flexoelectric smart aggregate according to claim 1, characterized in that, The piezoelectric driving element (6) is a piezoelectric ceramic sheet, a piezoelectric composite material, or a piezoelectric single crystal wafer; the piezoelectric driving element (6) and the vibration transmission structure are fixedly connected by a conductive adhesive layer (10).

3. The cement-based embedded high-pressure resistant bidirectional bending-tension piezoelectric smart aggregate according to claim 1, characterized in that, The conductive buffer (8) is one of conductive foam, conductive rubber or metal elastic sheet; the edge of the circuit board (7) is provided with an exposed ground conductive area, and the conductive buffer (8) is sandwiched between the ground conductive area and the crimping part (5).

4. The cement-based embedded high-pressure resistant bidirectional bending-tension piezoelectric smart aggregate according to claim 1, characterized in that, The elastic electrical connection structure (9) includes a spring pin, an elastic conductive probe, or a metal spring; the surface of the elastic electrical connection structure (9) is provided with a conductive plating layer; the extension and retraction direction of the elastic electrical connection structure (9) is perpendicular to the plane of the circuit board (7) and is located in the central region of the circuit board (7).

5. The cement-based embedded high-pressure resistant bidirectional bending-tension piezoelectric smart aggregate according to claim 1, characterized in that, The first housing (1) and the second housing (2) have complementary positioning stop structures on their snap-fit ​​edges. A sealing element is provided in the fitting gap of the positioning stop structure, and a sealing connection layer is provided at the external seam of the housing assembly.

6. The cement-based embedded high-pressure resistant bidirectional bending-tension piezoelectric smart aggregate according to claim 5, characterized in that, The positioning stop structure is an embedded fit between a boss and a groove; the sealing element is a structural adhesive, a sealing gasket, or a sealing ring; the sealing connection layer is a laser welding layer, an ultrasonic welding layer, or an adhesive layer.

7. The cement-based embedded high-pressure resistant bidirectional bending-tension piezoelectric smart aggregate according to claim 1, characterized in that, The working resonance frequency of the smart aggregate is functionally related to the curvature of the force-radiating structure, the wall thickness of the shell assembly, and the size of the force-transmitting component; by configuring the ratio of the thickness of the vibration transmission structure to the diameter of the piezoelectric drive element (6), the smart aggregate can generate overall bending and tension resonance in a preset low-frequency band.

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