Concrete corrosion detection device

Abstract

The utility model discloses a concrete corrosion detection device which comprises a detachable telescopic vehicle-mounted support mechanism and a salinity detection assembly arranged on the vehicle-mounted support mechanism, the salinity detection assembly comprises a device shell, a neutron source moderation shielding structure integrated on the inner side of the device shell and a plurality of BGO detectors with multi-angle detection, the plurality of BGO detectors are symmetrically distributed on the outer side of the neutron source moderation shielding structure and are arranged at intervals with the neutron source moderation shielding structure. According to the detection device, the detection system is optimized, the BGO detectors are symmetrically distributed, multi-angle detection is achieved, and the detection sensitivity is improved. The neutron source moderation shielding structure is integrated, the neutron source assembly is arranged on the inner side, and the neutron source moderation unit and the reflective shielding absorption unit are arranged on the outer side, so that the direction and energy of emitted neutrons are controlled, interference of redundant gamma rays is reduced, the signal-to-noise ratio of the BGO detector is increased, and the accuracy of non-destructive detection of a to-be-detected object is improved.

Description

A concrete corrosion detection device Technical Field

[0001] This utility model relates to the field of non-destructive testing technology, and specifically to a concrete corrosion detection device. Background Technology

[0002] Chloride corrosion is the most significant problem affecting the durability of concrete structures in near-shore bridges and highways. The use of antifreeze in winter also reduces the durability of concrete structures. When the chloride concentration exceeds a critical value, it corrodes steel and severely damages the strength of concrete structures, thus necessitating the development of chloride concentration measurement techniques. Gamma-ray neutron activation analysis (PGNAA) is one such technique that has proven to be an effective non-destructive elemental analysis method. Its basic principle is: when a thermal neutron irradiates a sample, the neutron is captured by the atomic nuclei in the sample and emits a transient γ emission during the (n,γ) reaction, approximately 10 -14 Emitted within seconds, its gamma energy ranges from 2 to 10 MeV. It is detected using a high-resolution gamma-ray spectrometer, and quantitative analysis is performed using characteristic peaks and net counts. Compared to other techniques such as X-ray fluorescence (XRF), it has advantages in determining the concentration of light elements (H, B, C, N, O, P, S, Cl) in materials. Furthermore, Cl exhibits higher sensitivity to PGNAA compared to other elements in concrete, such as Ca and Si, making it particularly suitable for detecting chlorine content.

[0003] However, there are few reports on the application of PGNAA in mobile devices for elemental analysis of concrete, and it is difficult to obtain specific information on concrete corrosion (such as the relative content of chlorine, the depth and horizontal position of the corrosion layer). Traditional PGNAA analysis equipment has problems such as large size, difficulty in movement, limited response information, and poor detection sensitivity. Summary of the Invention

[0004] The purpose of this invention is to address the limitations of traditional PGNAA (Progressive Neutron Gamma Analysis) technology, which is characterized by its large size and difficulty in mobility, by providing a concrete corrosion detection device. This device is based on PGNAA technology and allows for the detection of concrete components. It solves the problems of large size, poor mobility, and limited response information of traditional detection equipment by improving the single BGO detector into multiple symmetrically distributed BGO detectors, supporting multi-angle detection and thus improving detection sensitivity.

[0005] The technical solution adopted by this utility model to achieve its inventive purpose is: a concrete corrosion detection device, including a detachable telescopic vehicle-mounted support mechanism and a salt detection component disposed on the vehicle-mounted support mechanism. The salt detection component includes a device housing, a neutron source moderation shielding structure integrated inside the device housing, and multiple BGO detectors with multi-angle detection capabilities. The multiple BGO detectors are symmetrically distributed on the outside of the neutron source moderation shielding structure and spaced apart from it. This concrete corrosion detection device, by incorporating a detachable telescopic vehicle-mounted support mechanism, enables rapid detachment and connection with a mobile vehicle, allowing for telescopic connection with any desired mobile vehicle. During detection, it can extend and retract longitudinally to change the distance between the salt detection component and the target, obtaining more accurate detection results. The salt detection component mainly consists of a housing for installation and shielding against harmful radiation. A neutron source moderation shielding structure is integrated inside the housing. Multiple BGO detectors are evenly distributed on the outside of the neutron source moderation shielding structure. These multiple BGO detectors can perform multi-angle detection, and the spacing between the BGO detectors and the neutron source moderation shielding structure allows for a higher signal-to-noise ratio. During operation, the pulsed neutron source emits neutrons, which react with chlorine in the concrete being tested, producing characteristic gamma rays. The BGO detectors capture these gamma-ray signals and convert them into electrical signals. Because multiple evenly distributed BGO detectors perform detection simultaneously, and the detectors can change their detection direction according to the object being tested, the sensitivity and accuracy of the BGO detectors are improved. Integrating the salt detection component with a vehicle-mounted bracket allows for connection to different mobile vehicles, enabling flexible selection of different vehicles to meet the detection needs of various locations. This solves the problems of existing technologies that directly fix bulky detection equipment to vehicles, resulting in large equipment size, insufficient detection sensitivity, and poor mobility.

[0006] Preferably, the neutron source moderation shielding structure includes a device support assembly, a neutron source assembly, a neutron source moderation unit, and a reflective shielding absorption unit arranged sequentially from the inside to the outside on the device support assembly. The neutron source moderation shielding structure mainly integrates the neutron source assembly, the neutron source moderation unit, and the reflective shielding absorption unit through the device support assembly. The neutron source assembly is located on the inside to ensure no leakage of radioactive materials, while the neutron source moderation unit and the reflective shielding absorption unit are located on the outside to control the direction and energy of the emitted neutrons, prevent radiation damage to non-target objects or personnel, reduce interference from excess gamma rays, improve the signal-to-noise ratio of the BGO detector, and thus improve detection accuracy.

[0007] Preferably, the device support assembly includes an upper support member for connecting to the device housing and a lower support member for fixing the neutron source moderation shielding structure. The support assembly mainly includes an upper support member and a lower support member. The upper support member connects to the top of the device housing, while the lower support member securely connects the neutron source assembly, the neutron source moderation unit, and the reflective shielding absorption unit. It also ensures a planar structure for the neutron source moderation shielding structure, guaranteeing its height consistency with the detection target and thus improving detection accuracy. The upper and lower support members can be support plates, support shell covers, or any other shape as needed; no specific limitation is imposed, as long as the requirements of the neutron source moderation shielding structure are met.

[0008] Preferably, the neutron source assembly includes a neutron source and a neutron source shell disposed outside the neutron source. The neutron source assembly is fixed to the lower support member by a neutron source support base made of polyethylene. The neutron source assembly mainly includes the neutron source and the neutron source shell. The neutron source shell protects the neutron source, ensuring no leakage of radioactive materials. Simultaneously, the neutron source shell is fixed to the neutron source support base, thereby achieving stable installation and fixation of the neutron source assembly. The neutron source support base ensures a tight fit and fixation with the support member. Furthermore, the neutron source support base provides a secondary slowing effect on neutrons, increasing the energy density of thermal neutrons, improving neutron utilization, and enhancing the signal strength of the detector.

[0009] Preferably, the neutron source support base is provided with a neutron source fixing groove, and the lower support member has a mounting groove at its center. The neutron source support base is embedded in the mounting groove, and the bottom surface of the neutron source support base is flush with the bottom surface of the lower support member. To facilitate the installation and fixing of the neutron source assembly, a neutron source fixing groove is provided on the neutron source support base, and a mounting groove is provided on the lower support member 42 plate to facilitate the installation of the neutron source support base, thereby achieving the embedding of the neutron source support base and ensuring a tight fit between the neutron source support base and the lower support member.

[0010] Preferably, the neutron source moderation unit includes a polyethylene neutron source moderator with an open structure, the opening of which faces downwards and covers the outside of the neutron source assembly. The neutron source moderation unit is primarily an open neutron source moderator. Because the neutron source moderator is made of polyethylene, which has a high hydrogen atom content, neutrons primarily undergo elastic scattering with hydrogen atoms, thus significantly reducing the neutron energy.

[0011] Preferably, the reflective shielding and absorption unit includes a neutron reflective layer, a neutron shielding and absorption layer, and a gamma-ray shielding layer. The reflective shielding and absorption units are arranged in close contact with each other from the inside out, controlling the direction and energy of the emitted neutrons and preventing radiation damage to non-target objects or personnel. It also protects the BGO detector.

[0012] Preferably, the neutron reflector has a ring-shaped structure, with its opening facing downwards and covering the outside of the neutron source assembly. The neutron shielding absorption layer is arranged around the outside of the neutron reflector, and the gamma-ray shielding layer 83 is arranged around the outside of the neutron shielding absorption layer. Since the interaction between neutrons and the neutron moderator layer, neutron reflector layer, and neutron shielding absorption layer may generate gamma rays of specific energies, which can interfere with the BGO detector, a gamma-ray shielding layer is placed outside and attached to the neutron shielding absorption layer to reduce this interference. This ensures complete absorption of excess neutrons, preventing neutron radiation damage to the BGO detector, and reduces interference from excess gamma rays, thus improving the signal-to-noise ratio of the BGO detector.

[0013] Preferably, the BGO detector is spaced 2-3 cm apart from the neutron shielding and absorbing layer 82. Setting the BGO detector and the neutron shielding and absorbing layer apart by 2-3 cm allows the detector to achieve a higher signal-to-noise ratio.

[0014] Preferably, the device housing has a dome-shaped structure comprising a top, a housing, and a cover. The top is horizontal, the housing and top are inclined, and the cover is vertically connected to the housing in a ring shape. The dome-shaped housing is designed for lightweight construction and can be made of stainless steel for easy installation on the front of a small vehicle. The top facilitates the installation of the telescopic support mechanism and the fixation of the internal salt detection components. The inclined housing facilitates the spacing between the BGO detector 5 and the neutron source moderation shielding structure, and also concentrates neutron rays towards the target object, reducing the risk of neutron irradiation to the surrounding environment.

[0015] Preferably, the BGO detector is located inside the housing, near the casing. This placement of the BGO detector serves two purposes: firstly, it allows for a certain distance from the sub-source slowing shielding structure; secondly, it ensures that the BGO detector's angular rotation is not affected.

[0016] Preferably, the BGO detector is connected to the device housing via a detector bracket. A detector rotation mechanism is mounted on the bracket, and the BGO detector is connected to and rotates at multiple angles through this mechanism. The detector is mounted on a vehicle using a custom-designed bracket with a cushioning function to effectively absorb vibrations from the vehicle's movement, thus ensuring the detector's stability and detection accuracy during operation. The built-in circuitry supports connection to an onboard power supply, allowing real-time display of detection signals on the onboard terminal for convenient on-site operation and data analysis.

[0017] The beneficial effects of this invention are as follows: This concrete corrosion detection device, based on the concept of a vehicle-mounted concrete salt meter using PGNAA technology, integrates a neutron source moderation and shielding structure. The neutron source component is located on the inner side to ensure no leakage of radioactive materials, while the neutron source moderation unit and reflective shielding absorption unit are located on the outer side to control the direction and energy of emitted neutrons, prevent radiation damage to non-target objects or personnel, reduce interference from excess gamma rays, and improve the signal-to-noise ratio of the BGO detector, thereby improving the accuracy of non-destructive testing of the object under test. Simultaneously, the detection system is optimized by replacing a single BGO detector with multiple symmetrically distributed BGO detectors, supporting multi-angle detection to improve detection sensitivity. It can be connected to different mobile vehicles via a vehicle-mounted bracket mechanism to meet the detection needs of different locations. This solves the problems of existing technologies that directly fix bulky detection equipment to vehicles, resulting in large equipment size, insufficient detection sensitivity, and poor mobility. Attached Figure Description

[0018] Figure 1 is a structural schematic diagram of the concrete corrosion detection device of this utility model.

[0019] Figure 2 is a bottom view of the concrete corrosion detection device of this utility model.

[0020] Figure 3 is a horizontal sectional view of the concrete corrosion detection device of this utility model.

[0021] Figure 4 shows a comparison of the signal strength of the BGO detector in concrete corrosion detection device of this invention, which simulates chloride-corroded concrete and normal concrete using the MCNP program.

[0022] Figure 5 is a schematic diagram of an application structure of the concrete corrosion detection device of this utility model.

[0023] Figure 6 is a perspective structural diagram of one application of the concrete corrosion detection device of this utility model.

[0024] In the picture:

[0025] 1. Vehicle-mounted bracket mechanism; 2. Salt content detection component; 3. Neutron source moderation shielding structure.

[0026] 4. Device support assembly, 41. Upper support component, 42. Lower support component, 43. Embedded groove;

[0027] 5. BGO detector,

[0028] 6. Neutron source assembly; 61. Neutron source; 62. Neutron source housing; 63. Neutron source support base; 64. Neutron source fixing groove;

[0029] 7. Neutron source moderation unit; 71. Neutron source moderator; 72. Opening;

[0030] 8. Reflective shielding and absorption unit; 81. Neutron reflective layer; 82. Neutron shielding and absorption layer; 83. Gamma-ray shielding layer;

[0031] 9. Device outer casing; 91. Top of casing; 92. Casing; 93. Casing cover;

[0032] 10. Detector bracket; 11. Detector rotation mechanism;

[0033] 12. Mobile vehicle; 13. Object to be detected. Detailed Implementation

[0034] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings.

[0035] Example 1:

[0036] In the embodiments shown in Figures 1 and 2, a concrete corrosion detection device is provided. This device can be used for mobile detection in a vehicle-mounted manner, and can be flexibly moved in specific detection scenarios (such as roads, bridges, etc.) while ensuring the sensitivity and accuracy of the detector.

[0037] A concrete corrosion detection device mainly includes a vehicle-mounted support mechanism 1 and a salt content detection component 2. The salt content detection component 2 includes a device housing 9, a neutron source moderation shielding structure 3 integrated inside the device housing 9, and multiple BGO detectors 5 with multi-angle detection capabilities. The multiple BGO detectors 5 are symmetrically distributed on the outside of the neutron source moderation shielding structure 3 and are spaced at a certain distance from the neutron source moderation shielding structure 3. In this embodiment, four BGO detectors 5 are symmetrically distributed; in other embodiments, the number can be adjusted as needed.

[0038] As shown in Figure 1, the vehicle-mounted bracket mechanism 1 adopts a quick-disassembly structure and is telescopic. In use, the vehicle-mounted bracket mechanism 1 is quickly connected to a mobile vehicle. During detection, it can be extended or retracted longitudinally to change the distance to the target and obtain more accurate detection results. The quick-disassembly structure can be any structure that facilitates quick connection to a mobile vehicle, such as a snap-fit ​​structure, a screw-in structure, or a socket-type structure, etc.

[0039] The salinity detection component 2 mainly includes a device housing 9 connected to the vehicle-mounted bracket mechanism 1, a detection neutron source moderation shielding structure 3 set inside the device housing, and multiple BGO detectors 5.

[0040] Each of the BGO detectors 5 is connected to the device housing 9 via a detector bracket 10. A detector rotation mechanism 11 is provided on the detector bracket 10. The BGO detector 5 is connected to the detector rotation mechanism 11 and can rotate at multiple angles through the detector rotation mechanism 11.

[0041] As shown in Figures 1 and 2, in this embodiment, four BGO detectors 5 are respectively mounted on the inner wall of the device housing 9 via a detector rotation mechanism 11 and a detector bracket 10, and the four BGO detectors 5 are symmetrically distributed inside the device housing 5.

[0042] The device housing 9 has a dome-shaped structure comprising a top 91, a housing 92, and a cover 93. The top 91 is horizontally positioned, while the housing 92 is inclined to the top 91. The cover 93 is annularly and vertically connected to the housing 92. The BGO detector 5 is located inside the housing 92, close to the cover 93. This structural design of the device housing facilitates the concentration of neutron rays onto the target object while minimizing the risk of neutron irradiation to the surrounding environment.

[0043] The neutron source moderation shielding structure 3 includes a device support component 4, a neutron source component 6, a neutron source moderation unit 7, and a reflective shielding absorption unit 8.

[0044] The device support assembly 4 includes an upper support 41 for connecting to the device housing and a lower support 42 for fixing the neutron source moderation shielding structure. An embedding groove 43 is provided at the center of the lower support 42.

[0045] The neutron source assembly 6 includes a neutron source 61 and a neutron source housing 62 disposed outside the neutron source. The neutron source assembly 6 is fixed to the lower support member 42 by a neutron source support base 63 made of polyethylene. The neutron source assembly 6 includes a neutron source housing 62 arranged in an enclosing structure from the outside in. 252 Cf Neutron Source 61.

[0046] The neutron source support 63 is provided with a neutron source fixing groove 64. The neutron source support 63 is embedded inside the embedding groove 43, and the lower bottom surface of the neutron source support 63 is flush with the lower end surface of the lower support member 42. The neutron source support 63 can achieve secondary slowing down, increase the thermal neutron flux density, improve neutron utilization, and enhance the detector signal strength.

[0047] The neutron source moderation unit 7 includes a polyethylene neutron source moderator 71 with an opening 72, which is disposed on the outside of the neutron source assembly 6 with the opening facing downward.

[0048] As shown in Figures 1 and 3, the reflective shielding and absorption unit 8 includes a neutron reflective layer 81, a neutron shielding and absorption layer 82, and a gamma-ray shielding layer 83.

[0049] A neutron reflector layer 81 made of graphite is disposed outside the neutron source moderator 71. The neutron reflector layer is arranged in a ring-shaped structure around the outside of the neutron source component 6. A neutron shielding and absorbing layer 82 made of boron-containing polyethylene is disposed outside the neutron reflector layer 81. A gamma-ray shielding layer 8 is disposed outside the neutron shielding and absorbing layer 82, forming a multi-channel shielding of reflection, absorption and shielding to reduce the radiation damage to the outside world during neutron detection.

[0050] The neutron source assembly 6 is fixed to the lower support 42 via a neutron source support 63. During operation, the neutron source support 63 achieves secondary neutron slowing to increase the thermal neutron flux density, improve neutron utilization, and enhance the detector signal strength.

[0051] For the neutron source part 252 The Cf neutron source 61 is protected by a neutron source casing 62 to ensure no leakage of radioactive materials. The neutron source support 63 is tightly fitted with the lower support 42 and is used to support the neutron source assembly 6 (…). 252 The Cf neutron source 61 plays a stabilizing role and simultaneously achieves secondary neutron slowing.

[0052] The neutron source moderator 71, neutron reflector 81, neutron shielding absorption layer 82, and gamma-ray shielding layer 83 are closely fitted and coordinated from the inside out, with similar structures. They control the direction and energy of emitted neutrons and prevent radiation damage to non-target objects or personnel. The neutron shielding absorption layer 82 protects the BGO detector 5. Since the interaction between neutrons and the neutron source moderator 71, neutron reflector 81, and neutron shielding absorption layer 82 may generate gamma rays of specific energies, which can interfere with the BGO detector, a gamma-ray shielding layer 83 is placed outside and fitted to the neutron shielding absorption layer 82 to reduce this interference. This ensures complete absorption of excess neutrons, preventing neutron radiation damage to the BGO detector, and also reduces interference from excess gamma rays, improving the signal-to-noise ratio of the BGO detector.

[0053] For the detector part, the BGO detector 5 is fixed by the detector support 10 and the detector rotation mechanism 11. The detection direction can be changed as needed. According to the optimized parameters, the BGO detector 5 is set to be 2~3 cm away from the neutron shielding absorption layer 82, which can make the detector obtain a higher signal-to-noise ratio.

[0054] In addition to fixing the neutron source assembly 6, the neutron source moderation unit 7, and the reflective shielding absorption unit 8, the outer casing 9 of the device can also shield the gamma rays generated by the neutron reaction.

[0055] The working process of this concrete corrosion detection device is as follows:

[0056] During installation 252 When the Cf neutron source 61 is installed, it is fixed on the neutron source support 63. The stainless steel neutron source shell 62 ensures that radioactive materials do not leak. The neutron source and the neutron source shell form the neutron source assembly 6. The neutron source assembly 6 is installed through the neutron source support 63 to a position where it fits against the lower support 42, ensuring that the neutron source assembly 6 is stably protected and supported. After installation, the neutron source assembly 6 releases neutrons with a radioactivity of 100 μCi, and the detector immediately begins to operate.

[0057] When high-energy neutrons are transported to the neutron source moderator 71, because it is made of polyethylene with a high hydrogen atom content, the neutrons mainly undergo elastic scattering with the hydrogen atoms, thus greatly reducing the neutron energy. When the neutrons move to the neutron reflector 81 made of graphite, the neutrons can undergo scattering with carbon atoms, resulting in a large directional deflection. Then, most of the neutrons will continue to be transported towards the detection target, passing through the neutron source support 63 made of polyethylene again, which can achieve secondary moderation, increase the thermal neutron flux density, improve neutron utilization, and enhance the detector signal strength.

[0058] Considering that neutrons may escape and be reflected within the neutron reflector layer 81, a neutron shielding and absorbing layer 82 made of boron-containing polyethylene is further provided to reduce damage to the stainless steel neutron source casing 62 and the external environment. This layer can absorb neutrons or reduce their energy, minimizing the impact of neutron irradiation. A gamma-ray shielding layer 83 is attached to the outside of the neutron shielding and absorbing layer 82 to minimize the shielding of gamma-ray signals unrelated to the target.

[0059] Based on MNCP simulation optimization, placing the BGO detector 5 2-3 cm away from the gamma-ray shielding layer 83 yields better sensitivity. The outermost layer, the device casing 9, secures the neutron source and the BGO detector 5, and additionally shields them from harmful radiation.

[0060] Overall, the neutron reflector 81, the neutron shielding and absorption layer 82, and the device shell 9 form a three-layer barrier of reflection, absorption, and shielding to reduce radiation damage to the outside world during neutron detection.

[0061] Most neutron rays are deflected at a large angle after passing through the neutron reflector layer 81, changing direction and being transported downwards. After secondary slowing down by the neutron source moderator 71, many thermal neutrons are generated and directed towards the ground. Due to the strong penetrating power of neutrons, they can travel to deeper parts of the concrete. If the chlorine content in a certain area exceeds the standard, the thermal neutrons have a certain probability of undergoing a radiation capture reaction with chlorine atoms, emitting gamma rays of specific energy from inside the concrete. The gamma ray signal is received by the BGO detector 5, interacts with atoms in the BGO crystal, excites electron transitions and emits fluorescence, and is then converted into an electrical signal by a photomultiplier tube for analysis. Chlorine typically has four characteristic peaks corresponding to four different energies. If the count of characteristic peaks exceeds the normal value by 10%-20%, it indicates that the concrete structure may be corroded by chlorine. Such elemental detection can achieve long-term and wide-range detection requirements through the mobile vehicle-mounted support mechanism 1.

[0062] Figure 4 shows a comparison of BGO detector signal intensities between concrete corroded by chloride salts and normal concrete simulated using the MCNP program. The characteristic peaks of Cl element in the signal of concrete corroded by 20 kg / m³ of chloride salts (NaCl) are 6.11 MeV and 6.62 MeV, respectively, and their intensities are significantly higher than those of normal concrete.

[0063] The concrete salinity testing device mainly includes: a vehicle-mounted support mechanism 1, and a radioactive isotope. 252 The system comprises a Cf neutron source 2, a stainless steel neutron source casing 62, a neutron source moderator 71, a neutron reflector 81, a neutron shielding and absorbing layer 82, a gamma-ray shielding layer 83, a BGO detector 5, a stainless steel device casing, and a detachable neutron source support 63. Its core components and design include the following:

[0064] 252 The Cf neutron source is housed within a detachable polyethylene neutron source casing 62, ensuring a tight fit with the polyethylene neutron source moderator 71 to achieve secure neutron source fixation and effective moderation of emitted neutrons. The polyethylene neutron source casing 62, the polyethylene neutron source moderator 71, the graphite neutron reflector layer 81, and the boron-containing polyethylene neutron shielding and absorbing layer 82 work together to form a comprehensive neutron reflection, moderation, and absorption system. This structure not only effectively concentrates neutron rays onto the target object but also minimizes the risk of neutron irradiation to the surrounding environment.

[0065] The gamma-ray shielding layer 83 and the neutron shielding and absorbing layer 82 are tightly bonded together to further shield radiation and ensure the safety of the device. All of the above structures are secured by a stainless steel housing 9 to enhance the stability and durability of the device. The top of the stainless steel housing 9 is connected to the vehicle-mounted bracket mechanism 1, allowing the device to be easily installed on small vehicles for convenient mobility.

[0066] The BGO gamma ray detector is also secured by a stainless steel housing 9, which is designed to be lightweight for easy mounting on the front of a small vehicle.

[0067] Multiple detector brackets 10 are symmetrically arranged near the edge of the inner side of the device housing 9. A detector rotation mechanism 11 is connected to each detector bracket 10. The BGO detector 5 is connected to the detector rotation mechanism 11 and can rotate at an angular position. The detector brackets 10 have a buffering function, effectively absorbing vibrations caused by vehicle movement, thereby ensuring the stability and detection accuracy of the detector during operation. The built-in circuitry of the BGO detector 5 can be connected to the vehicle's power supply, allowing real-time display of detection signals on the vehicle terminal, facilitating on-site operation and data analysis.

[0068] The working principle of the concrete salt content detection device is as follows: During operation, the pulsed neutron source 61 emits neutrons, which react nuclearly with chlorine in the concrete being tested, producing characteristic gamma rays. The BGO detector 5 captures these gamma ray signals and converts them into electrical signals. The signal processing module further amplifies, filters, and processes the signals to ultimately determine the concentration of chlorine in the sample. Through the data transmission module, the analysis results can be transmitted in real time to a host computer or remote monitoring equipment, facilitating remote monitoring and data recording.

[0069] As shown in Figures 5 and 6, the detection method of this concrete salt content detection device is as follows:

[0070] 1. On-site detection: After the neutron source 61 begins emitting neutrons, a small mobile vehicle 12 slowly drives into the object 13 to be detected (such as a bridge or road) in the detection area to detect the chlorine content of the concrete surface in real time. If an area with a significantly increased chlorine content is detected, the local extension or translation function of the BGO detector can be used for further localization to ensure the accuracy of the data.

[0071] 2. Data Interpretation and Risk Assessment: During the testing process, when the characteristic peak count value of chlorine exceeds the normal count value of concrete materials by 10%-20%, it can be determined that there is a potential risk of chlorine corrosion in that area. This information can be used to promptly assess the health status of the concrete structure, providing data support for maintenance and repair.

[0072] 3. The design and method of this mobile detection device, which incorporates PGNAA technology, has high sensitivity and accuracy. It also enables efficient and convenient on-site detection through a vehicle-mounted structure, and can be widely used for corrosion detection and risk assessment of concrete materials in bridges, tunnels and roads.

[0073] This concrete salinity detection device utilizes isotopic neutron sources and neutron transient gamma analysis technology to design a compact, vehicle-mounted concrete corrosion detection system—an integrated vehicle-mounted system. This system integrates the neutron source, detector, signal processing, and data analysis modules, enhancing the device's portability and field application capabilities. Furthermore, it eliminates the need for external accelerator power, making the system more compact and lightweight, suitable for mobile vehicle-mounted detection. In terms of detection methods, a spatially symmetrical four-detector structure is designed, effectively expanding the detector's spatial response information. An experimental method using small samples to simulate on-site detection is proposed. Experimental data on the correlation between multidimensional response parameters and corrosion depth is learned using different SVR models. An intensity correction coefficient based on spatial geometric relationships is introduced, enabling more accurate on-site evaluation of concrete corrosion levels.

[0074] The specific embodiments / examples described above are specific implementations of this utility model, used to illustrate the concept of this utility model. They are all illustrative and exemplary, and should not be construed as limiting the implementation methods or scope of this utility model. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein, all of which are within the protection scope of this utility model.

Claims

1. A concrete corrosion detection device, characterized in that: The device includes a removable telescopic vehicle-mounted bracket mechanism (1) and a salt detection component (2) installed in the vehicle-mounted bracket mechanism (1). The salt detection component (2) includes a device housing (9), a neutron source moderation shielding structure (3) integrated inside the device housing (9), and multiple BGO detectors (5) with multi-angle detection. The multiple BGO detectors (5) are symmetrically distributed on the outside of the neutron source moderation shielding structure (3) and are spaced apart from the neutron source moderation shielding structure (3).

2. The concrete corrosion detection device according to claim 1, characterized in that: The neutron source moderation shielding structure (3) includes a device support assembly (4), a neutron source assembly (6), a neutron source moderation unit (7), and a reflective shielding absorption unit (8).

3. The concrete corrosion detection device according to claim 2, characterized in that: The device support assembly (4) includes an upper support (41) for connecting to the device housing and a lower support (42) for fixing the neutron source moderation shielding structure.

4. The concrete corrosion detection device according to claim 3, characterized in that: The neutron source assembly (6) includes a neutron source (61) and a neutron source housing (62) disposed outside the neutron source. The neutron source assembly (6) is fixed to the lower support (42) by a neutron source support base (63) made of polyethylene.

5. The concrete corrosion detection device according to claim 4, characterized in that: The neutron source support base (63) is provided with a neutron source fixing groove (64), and the lower support member (42) is provided with an embedding groove (43) at its center. The neutron source support base (63) is embedded in the embedding groove (43), and the bottom surface of the neutron source support base (63) is flush with the bottom surface of the lower support member (42).

6. The concrete corrosion detection device according to claim 2, characterized in that: The neutron source moderation unit (7) includes a polyethylene material neutron source moderator (71) with an open (72) structure, and the neutron source moderator (71) is covered on the outside of the neutron source assembly (6) with the opening facing downward.

7. The concrete corrosion detection device according to claim 2, characterized in that: The reflective shielding and absorption unit (8) includes a neutron reflective layer (81), a neutron shielding and absorption layer (82), and a gamma-ray shielding layer (83).

8. The concrete corrosion detection device according to claim 7, characterized in that: The neutron reflector (81) has an overall ring-shaped structure. The neutron reflector (81) is positioned with its opening facing downwards and is placed over the outside of the neutron source assembly (6). The neutron shielding absorption layer (82) is arranged around the outside of the neutron reflector (81), and the gamma-ray shielding layer (83) is arranged around the outside of the neutron shielding absorption layer (82). The BGO detector (5) is spaced 2 to 3 centimeters apart from the neutron shielding absorption layer (82).

9. The concrete corrosion detection device according to any one of claims 1 to 8, characterized in that: The device housing (9) has a cover structure with a top (91), a housing (92) and a cover (93). The top (91) is horizontal, the housing (92) and the top (91) are inclined, and the cover (93) is vertically connected to the housing (92) in a ring. The BGO detector (5) is located inside the housing (92) and close to the cover (93).

10. The concrete corrosion detection device according to any one of claims 1 to 8, characterized in that: The BGO detector (5) is connected to the device housing (9) via a detector bracket (10). A detector rotation mechanism (11) is provided on the detector bracket (10). The BGO detector (5) is connected to the detector rotation mechanism (11) and rotates at multiple angles through the detector rotation mechanism (11).

Images