Real-time monitoring device for steel bar protective layer

Abstract

The invention provides a real-time monitoring device for a reinforcing steel bar protective layer, and relates to the field of building construction, and the device comprises a sensor module which comprises an ultrasonic thickness gauge for measuring the thickness of the reinforcing steel bar protective layer and an electromagnetic inductor for measuring the performance of a reinforcing steel bar; the communication module is used for receiving the measurement information of the sensor module and converting the measurement information into a data form for transmission; the information processing module is used for receiving and processing the data information of the communication module; the power supply module is used for providing energy support for the sensor module and the communication module; the protection shell is fixed on the reinforcement cage in the reinforcement protection layer; and the sensor module, the power supply module and the communication module are all arranged in the protective shell. The method has the effect of improving the accuracy of monitoring the safety performance of the reinforcing steel bars in the reinforcing steel bar protection layer.

Description

Technical Field

[0001] The present application relates to the field of building construction technology, and in particular to a real-time monitoring device for a steel bar protective layer. Background Art

[0002] The steel bar protective layer refers to a concrete layer of a certain thickness set on the outside of the steel bar in the reinforced concrete structure to protect the steel bar from external environmental damage (such as corrosion) or fire and to ensure the structural stress performance. The thickness of the steel bar protective layer has a significant impact on the stress performance, durability and frost resistance of the building, and is directly related to the safety and life of the building. If the thickness of the steel bar protective layer is too small, the steel bars inside it are prone to rust, rust expansion and cracking, endangering the service life of the building structure. If the thickness of the steel bar protective layer is too large, it is easy to cause concrete cracking or affect the bearing capacity of the building.

[0003] In related technologies, the steel bar protective layer may be disturbed during the pouring process, such as the impact of vibrating rods, wind and other external factors, which may cause the steel bar to tilt. During the pouring process, a dedicated person is usually arranged to observe whether the steel bar is disturbed, and the pouring process is recorded through surveillance cameras for retrospective inspection. After the pouring is completed, the external steel bar protective layer and the internal steel bar are inspected by manually carrying a detection instrument.

[0004] With regard to the above-mentioned related technologies, the error in observing the state of the steel bars by humans during the pouring process is large. After the pouring is completed, the internal steel bar state is detected from the surface of the steel bar protective layer by manually carrying detection instruments, which takes a long time to locate the steel bars. In addition, the external environment, such as humidity and electromagnetic interference, has a great impact on the detection data. Moreover, it is difficult to detect the rust state of the internal steel bars from the surface of the steel bar protective layer, resulting in low accuracy in monitoring the safety performance of the steel bars in the steel bar protective layer. Summary of the invention

[0005] In order to improve the problem of low accuracy in monitoring the safety performance of steel bars in a steel bar protective layer, the present application provides a real-time monitoring device for a steel bar protective layer.

[0006] The present application provides a real-time monitoring device for steel bar protective layer, which adopts the following technical solution: A real-time monitoring device for a steel bar protective layer, comprising: A sensor module, including an ultrasonic thickness gauge for measuring the thickness of the steel bar cover and an electromagnetic sensor for measuring the steel bar performance; A communication module, used to receive the measurement information of the sensor module and convert the measurement information into data form for transmission; An information processing module, used for receiving and processing data information from the communication module; A power module, used to provide energy support for the sensor module and the communication module; and The protective shell is fixed on the steel cage inside the steel protection layer; The sensor module, power module and communication module are all arranged inside the protective shell.

[0007] Furthermore, the protective shell and the sensor modules, communication modules and power modules therein are provided in multiple groups and are respectively arranged at different positions of the steel cage in the steel protection layer.

[0008] Furthermore, the plurality of sensors are respectively arranged at the corners, center or nodes of the steel cage.

[0009] Furthermore, the density layout of the plurality of sensors is dynamically adjusted according to the shape and size specifications of the steel cage.

[0010] Furthermore, the ultrasonic thickness gauge probe protrudes from the protective shell in a horizontal direction, and the electromagnetic sensor probe protrudes from the protective shell in a vertical direction.

[0011] Furthermore, the ultrasonic thickness gauge probe is provided with a first sealing layer for sealing the protective shell and a coupling layer for serving as a signal transmission medium, the sealing layer is located between the ultrasonic thickness gauge probe and the protective shell, and the coupling layer is provided on the signal surface of the ultrasonic thickness gauge probe.

[0012] Furthermore, the electromagnetic sensor probe is provided with a second sealing layer for sealing the protective shell and a shielding layer for reducing external interference, the second sealing layer is located between the electromagnetic sensor and the protective shell, and the shielding layer wraps the part of the electromagnetic sensor probe that leaks out of the protective shell.

[0013] Furthermore, the sensor module, the power module and the communication module are packaged by low-pressure injection molding.

[0014] Furthermore, the power line of the power module and the signal line of the communication module are combined into a multi-core cable, and the multi-core cable passes through the steel bar protective layer and is connected to the external power supply and information processing module.

[0015] Furthermore, the power lines and signal lines inside the multi-core cable are wrapped with an isolation layer.

[0016] In summary, the present application includes at least one of the following beneficial technical effects: 1. The sensor module is embedded in the steel bar protective layer through the protective shell, so that the monitoring device can understand the various states and data of the steel bar protective layer and the internal steel bars in real time. When an abnormality occurs, the abnormal part and the cause of the abnormality can be locked in the first time, so that the steel bar protective layer can detect the abnormality in time during the pouring and solidification process, make adjustments in the first time, and reduce the possibility of rework. In the later use, the state of the steel bar protective layer can be continuously monitored in real time, and the real-time and accuracy of the monitoring of the steel bar protective layer can be improved; 2. By setting up an ultrasonic thickness gauge and an electromagnetic sensor, and setting the ultrasonic thickness gauge probe in the horizontal direction and the electromagnetic sensor probe in the vertical direction, the axial direction of the ultrasonic thickness gauge probe is perpendicular to the axial direction of the main steel bar of the steel cage, which is convenient for accurately measuring the thickness of the steel bar protective layer, and the axial direction of the electromagnetic sensor probe is parallel to the axial direction of the main steel bar of the steel cage, so as to improve the induction efficiency and facilitate the detection of defects such as rust and cracks on the surface and inside of the steel bar. In addition, the built-in electromagnetic sensor greatly shortens the distance between the electromagnetic sensor and the steel bar, which overcomes the disadvantage that when the electromagnetic sensor is external, the eddy current detection is only applicable to the protective layer of steel bars with small thickness; 3. By setting a sealing layer between the protective shell and the ultrasonic thickness gauge probe and the electromagnetic sensor probe, and setting a coupling layer on the signal surface of the ultrasonic probe, and setting a shielding layer on the part of the electromagnetic sensor probe that leaks out of the protective shell, the ultrasonic thickness gauge probe and the electromagnetic sensor probe leaking out of the protective shell are convenient for monitoring the performance of the steel bar protective layer. The sealing layer can isolate the protective shell from the casting material of the steel bar protective layer and protect the internal electrical components; the coupling layer can reduce the acoustic impedance difference during the sound wave measurement process of the ultrasonic thickness gauge, improve the transmission efficiency of the sound wave, and protect the ultrasonic thickness gauge probe; the shielding layer can reduce external electromagnetic interference, enhance the stability of the electromagnetic sensor transmission and receiving signals, and improve the measurement accuracy.

[0017] 4. By setting sensors at different key positions on the steel cage, the key parts of the steel cage can be inspected at the same time, which is more accurate than manual inspection, optimizes the steps of manual quality inspection, improves work efficiency, and greatly improves quality inspection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a schematic diagram of the installation of the monitoring device of an embodiment of the present application.

[0020] Figure 2It is a schematic diagram of an ultrasonic thickness gauge probe and an electromagnetic sensor probe according to an embodiment of the present application.

[0021] Figure numerals: 1. main steel bar; 2. stirrups; 3. protective shell; 4. ultrasonic thickness gauge probe; 5. electromagnetic sensor probe. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] The embodiment of the present application discloses a real-time monitoring device for a steel bar protective layer, which is specifically used to measure the safety performance of steel bars in bridge piers. The real-time monitoring device for a steel bar protective layer includes a sensor module, a communication module, an information processing module, a power module, and a protective shell 3. The sensor module, the communication module, the power module, and part of the information processing module are all arranged in the protective shell 3. Since the concrete pressure is relatively large when the bridge pier is cast, and the concrete is in an alkaline and humid environment, the protective shell 3 needs to be made of high corrosion resistance and high strength materials, such as stainless steel or aluminum alloy. By reserving a mounting seat on the protective shell 3 and opening a through hole on the mounting seat, and by passing a steel wire rope or a stainless steel tie through the through hole, the protective shell 3 is firmly fixed to the main steel bar 1 of the steel cage inside the bridge pier. The fixed protective shell 3 can withstand the extrusion of concrete without deviation to ensure the measurement accuracy.

[0024] Specifically, the sensor module includes an ultrasonic thickness gauge for measuring the thickness of the protective layer and an electromagnetic sensor for measuring the performance of the steel bar. The communication module is used to receive the measurement information of the sensor module and convert the measurement information into data for transmission. The communication module can use wireless communication or wired communication. Wireless communication has the advantages of surface wiring and flexible deployment, including but not limited to communication methods such as Wi-Fi, Bluetooth or LoRa; wired communication has the advantages of stability, strong anti-interference and low cost. It is connected to the external information processing module through RS485 or CAN bus protocol and multi-core cable. The information processing module is used to receive and process the data information of the communication module. The information processing module includes an embedded system combined with an external computer. The embedded system is responsible for real-time data collection and preliminary processing. The external computer or cloud platform is used for in-depth analysis and display of data analysis results, and can store data for a long time. The power module is used to provide energy support for the sensor module and the communication module. The power module needs to have long-term stable power supply requirements in harsh environments, taking into account durability and safety. It specifically includes batteries, charging interfaces and control circuits. The batteries use lithium batteries or lithium iron phosphate batteries and are packaged in a waterproof, shockproof and corrosion-resistant manner to improve the safety of the batteries. The charging interface is connected to the external power supply through the concrete layer via a charging cable to maintain the battery's continuous power supply capability. The control circuit controls the battery's opening and closing through the communication module, and can remotely display the remaining battery power. Through the control circuit, the battery can be powered periodically, so that the detection device can collect data periodically, reducing continuous operation time and reducing energy consumption.

[0025] Before pouring the pier, the protective shell 3 wrapped with the sensor module, communication module and power module is fixed on the main steel bar 1 of the steel cage. During the pouring of the pier, the monitoring device can monitor the status of the steel cage at any time and respond immediately when an abnormality occurs, so that the construction personnel can make timely adjustments and reduce project losses. After the pouring is completed, the monitoring device can continuously detect the quality of the pier and upload the detection data. The built-in detection device can reduce the impact of the external environment on the measurement data, reduce measurement errors, and greatly improve the accuracy of the sensor module measurement data.

[0026] Preferably, the protective housing 3 and the sensor modules, communication modules and power modules therein are provided in multiple groups, and are respectively arranged at different positions of the steel cage in the steel protection layer, such as Figure 1 As shown. The positions and spacings of the multiple protective shells 3 need to be determined according to actual needs. By monitoring different positions of the bridge pier through sensor modules at different positions, the accuracy of the measurement data of the monitoring device is further improved.

[0027] Specifically, multiple sensor modules need to be set at key points of the steel cage, including the corners, center or nodes of the steel cage. The corners are where the concrete thickness deviation is large and quality problems are prone to occur. The center is where the steel cage is handled more concentratedly and is easily damaged. The node is the welding node of the steel cage. The monitoring device can monitor the quality and strength of the welding point. By setting multiple sensors at various key points, the steel bars can be monitored in real time at the most vulnerable locations, thereby greatly improving the accuracy of monitoring.

[0028] Since the arrangement of sensor modules is too dense, signal interference will occur between sensor modules, and too sparse will make many key parts of the steel cage difficult to monitor, it is necessary to reasonably arrange the density of multiple sensor modules. Specifically, the density layout of multiple sensors is adjusted according to the shape and size specifications of the steel cage, including equidistant arrangement, partition arrangement and targeted arrangement. The equidistant arrangement is suitable for non-key node positions of the steel cage. The distance between sensor modules is controlled at equal distances, and the distance should not exceed the maximum value of the sensor's sensing range to ensure data integrity; the partition arrangement is suitable for positions where the steel cage has a complex shape and higher requirements in local areas. The steel cage is divided into key monitoring areas and general monitoring areas. The key monitoring area includes the corner position, curved section and node position of the steel cage, and the general monitoring area is the straight section of the steel cage. The sensor layout spacing in the key area should not exceed half of the maximum value of the sensor sensing range, and the sensor layout spacing in the general monitoring area should not exceed the maximum value of the sensor sensing range; the targeted arrangement is suitable for complex steel cages (such as special-shaped cross-sections) or steel cages with specific monitoring requirements (such as stress concentration points and non-standard structural inflection points). The targeted arrangement is based on the priority coverage of key positions of the steel cage, and at least one sensor module is set at each key position.

[0029] Preferably, in order to further improve the measurement accuracy of the monitoring device, the ultrasonic thickness gauge probe 4 protrudes from the protective housing 3 in the horizontal direction, and the electromagnetic sensor probe 5 protrudes from the protective housing 3 in the vertical direction, such as Figure 2As shown. Since the detection direction of ultrasonic measurement of the thickness of bridge pier concrete is perpendicular to the axis direction of the main steel bar 1, the probe axis of the ultrasonic thickness gauge is set perpendicular to the axis of the main steel bar 1, that is, the ultrasonic thickness gauge probe 4 is set horizontally, which can reduce the measurement error caused by angle deviation, thereby greatly improving the accuracy of detecting the thickness of bridge pier concrete, and can also reduce interference with the electromagnetic sensor set in the vertical direction. The electromagnetic induction probe is set in the vertical direction, so that the coil axis inside the electromagnetic induction probe is parallel to the axis of the main steel bar 1, and can be close to the surface of the main steel bar 1, thereby improving the electromagnetic induction efficiency and increasing the measurement sensitivity, so as to accurately detect defects such as rust and cracks on the surface and inside of the steel bar, overcoming the defect that the traditional external electromagnetic reactor is only suitable for the protective layer of small thickness steel bars when performing eddy current detection.

[0030] In order to further reduce the error of the measurement data of the monitoring device, the ultrasonic thickness gauge probe 4 is provided with a first sealing layer for sealing the protective shell 3 and a coupling layer for serving as a signal transmission medium. The protective shell 3 is provided with a groove near the ultrasonic thickness gauge probe 4, and the first sealing layer is arranged in the groove. The first sealing layer is used to prevent concrete slurry, moisture and dust from entering the protective shell 3, thereby effectively protecting the electrical components in the protective shell 3. The first sealing layer is sealed with epoxy resin, and the epoxy resin can form a rigid sealing layer after curing, thereby effectively preventing the slow setting soil from passing through; the coupling layer can be made of silicone or elastic resin to reduce the acoustic impedance of the ultrasonic wave when it travels between the ultrasonic thickness gauge probe 4 and the concrete, so as to ensure the efficient transmission of the ultrasonic signal. The coupling layer needs to be coated on the signal surface of the ultrasonic thickness gauge probe 4, that is, the ultrasonic transmitting surface. The electromagnetic induction probe 5 is provided with a second sealing layer for sealing the protective shell 3 and a shielding layer for reducing external interference. The second sealing layer is fixed between the electromagnetic induction probe and the protective shell 3 using the same material and method as the first sealing layer; the shielding layer is wrapped around the part of the electromagnetic induction probe that leaks out of the protective shell 3. The shielding layer is made of conductive material, such as a metal mesh, metal foil or conductive rubber with good conductivity. By setting the shielding layer, the anti-interference ability of the electromagnetic sensor can be effectively improved, further ensuring the stability and accuracy of the signal, and avoiding interference of external electromagnetic waves or environmental noise on the probe signal.

[0031] Preferably, the sensor module, power module and communication module are packaged by low-pressure injection molding. Specifically including mold design, electronic component pretreatment and injection molding. During the mold design process, the mold is designed according to the shape of each module, including the sensor module, communication module, and power module, and the probe interface and cable channel are reserved on the mold, and hot melt adhesive is selected as the injection molding material. Electronic component pretreatment includes assembling and testing the sensor module, power module, and communication module to ensure normal function. During the injection molding process, each module is placed in the mold to ensure that the position of the probe, cable interface and other parts is accurate, and low-pressure injection molding is performed to control the injection molding pressure within the range of 0.1-5Mpa to reduce the possibility of damage to precision components. The injection molding temperature is controlled within the low melting point range, that is, within the range of 120-200°C. After the injection molding is completed, cooling molding is performed. By low-pressure injection molding of each module, the corrosion-resistant and impact-resistant injection molding material improves the durability of the detection device, and can achieve waterproof sealing, greatly improve the stability of the detection device, and the integrated setting can facilitate the installation of parts and reduce construction costs.

[0032] Preferably, the power line of the power module and the signal line of the communication module are combined into a multi-core cable, and the multi-core cable passes through the steel bar protective layer to connect with the external power supply and information processing module. Through integrated wiring, the wiring of the device can be simplified, the cable crossing and redundancy can be reduced, the arrangement and fixation of the cables can be facilitated, the construction difficulty can be reduced, the penetration hole position can be reduced, and the sealing performance of the protective shell 3 can be improved.

[0033] Preferably, the power lines and signal lines inside the multi-core cable are wrapped with an isolation layer. The isolation layer needs to be made of materials that are resistant to high temperatures and corrosion and have excellent insulation properties, including but not limited to polyethylene, polyvinyl chloride, polyimide and other materials, and is shielded and isolated in conjunction with an aluminum foil shielding layer or a tube braided mesh and other shielding layers, thereby achieving electrical insulation, reducing the stability of short circuits, and being able to shield electromagnetic interference, thereby improving the stability of signal transmission.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A real-time monitoring device for steel bar protective layer, characterized in that: include: A sensor module, including an ultrasonic thickness gauge for measuring the thickness of the steel bar cover and an electromagnetic sensor for measuring the steel bar performance; A communication module, used to receive the measurement information of the sensor module and convert the measurement information into data form for transmission; An information processing module, used for receiving and processing data information from the communication module; A power module, used to provide energy support for the sensor module and the communication module; and The protective shell is fixed on the steel cage inside the steel protection layer; The sensor module, power module and communication module are all arranged inside the protective shell.

2. The real-time monitoring device for steel bar protective layer according to claim 1 is characterized in that: The protective shell and the sensor modules, communication modules and power supply modules therein are provided in multiple groups and are respectively arranged at different positions of the steel cage in the steel protection layer.

3. The real-time monitoring device for steel bar protective layer according to claim 2 is characterized in that: The multiple sensor modules are respectively arranged at the corner positions, center positions or node positions of the steel cage.

4. The real-time monitoring device for steel bar protective layer according to claim 3 is characterized in that: The density layout of the multiple sensor modules is adjusted according to the shape and size specifications of the steel cage.

5. The real-time monitoring device for steel bar protective layer according to claim 1 is characterized in that: The ultrasonic thickness gauge probe protrudes from the protective shell in a horizontal direction, and the electromagnetic sensor probe protrudes from the protective shell in a vertical direction.

6. The real-time monitoring device for steel bar protective layer according to claim 5 is characterized in that: The ultrasonic thickness gauge probe is provided with a first sealing layer for sealing the protective shell and a coupling layer for serving as a signal transmission medium. The sealing layer is located between the ultrasonic thickness gauge probe and the protective shell, and the coupling layer is arranged on the signal surface of the ultrasonic thickness gauge probe.

7. The real-time monitoring device for steel bar protective layer according to claim 5 is characterized in that: The electromagnetic sensor probe is provided with a second sealing layer for sealing the protective shell and a shielding layer for reducing external interference. The second sealing layer is located between the electromagnetic sensor and the protective shell, and the shielding layer wraps the part of the electromagnetic sensor probe that leaks out of the protective shell.

8. The real-time monitoring device for steel bar protective layer according to claim 1 is characterized in that: The sensor module, power module and communication module are packaged by low-pressure injection molding.

9. A real-time monitoring device for steel bar protective layer according to claim 1, characterized in that: The power line of the power module and the signal line of the communication module are combined into a multi-core cable, and the multi-core cable passes through the steel bar protective layer and is connected to the external power supply and the information processing module.

10. A real-time monitoring device for steel bar protective layer according to claim 9, characterized in that: The power lines and signal lines inside the multi-core cable are both wrapped with an isolation layer.

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