A reinforced concrete corrosion monitoring sensor

Abstract

The reinforced concrete corrosion monitoring sensor of the present application comprises a sensor framework, a sensor base and a sensor top cover; a resistivity measuring test piece, a resistivity test piece spacer and a corrosion measuring test piece are sleeved outside the cylindrical sensor framework; the sensor top cover is fixed at the front end of the sensor framework, one end of the sensor base is connected with the rear end of the sensor framework through screw threads, and the other end of the sensor base is connected with a signal interface socket; the inner walls of the resistivity measuring test piece and the corrosion measuring test piece are both provided with wire positioning columns which extend into the sensor framework and are connected with corresponding wire terminals of the signal interface socket through wires; the corrosion measuring test piece is made of a metal material with the same brand as the steel bar to be monitored. The sensor can not only monitor the steel bar corrosion speed, but also can synchronously monitor the steel bar service micro-environment information related to the steel bar corrosion, such as temperature, humidity and concrete resistivity, so as to provide more comprehensive data for diagnosing the steel bar corrosion state.

Description

Technical Field

[0001] This invention relates to the field of reinforced concrete monitoring, specifically a sensor for monitoring corrosion of reinforced concrete. Background Technology

[0002] With the rapid development of my country's transportation industry, especially the construction of high-grade highways and cross-sea bridges between coastal cities, reinforced concrete structures, combining the advantages of steel and concrete, have become the preferred form in road and bridge construction design, and their application is very widespread. However, along with the extensive use of reinforced concrete, it has also been observed that reinforced concrete structures suffer from premature cracking and pavement layer detachment due to various reasons. In this process, the corrosion of the steel reinforcement inside the concrete is the root cause of the deterioration and reduced durability of reinforced concrete.

[0003] Corrosion of reinforced concrete refers to the phenomenon where steel reinforcement embedded in concrete comes into contact with moisture or corrosive media (usually chloride ions) entering the concrete structure, resulting in chemical or electrochemical reactions that cause discoloration and corrosion on the surface of the steel reinforcement, producing corrosion products that can be observed with the naked eye. Corrosion reduces the bond strength between the steel reinforcement and the concrete, and the resulting corrosion products expand in volume, causing cracks and spalling in the concrete structure. Therefore, monitoring corrosion in reinforced concrete is of significant theoretical and practical importance for improving its durability.

[0004] Traditional methods for monitoring reinforced concrete mainly include: resistance probes, which are widely used in Europe and America to detect steel corrosion in concrete structures; and acoustic emission methods, which utilize the expansion of corrosion products during steel corrosion in concrete, releasing some energy as emitted sound waves. Acoustic emission probes can sensitively detect the location and intensity of the emission source. However, it is difficult to avoid interference from other acoustic emissions, making it difficult to establish a correlation between the level of steel corrosion activity and the intensity of acoustic emission. Currently, real-time monitoring technologies for steel corrosion are mostly in the laboratory research stage, with few technologies and devices successfully applied to engineering projects. There is a lack of mature, reliable online monitoring sensors for concrete steel corrosion and practical engineering implementation plans. Summary of the Invention

[0005] To address the aforementioned technical problems, the purpose of this invention is to provide a sensor for monitoring corrosion of reinforced concrete.

[0006] In view of the many shortcomings of existing methods for monitoring corrosion of reinforced concrete, this invention provides an engineerable, pre-embedded sensor for monitoring corrosion of reinforced concrete.

[0007] This invention provides a sensor for monitoring the corrosion of reinforced concrete, comprising: a sensor frame, a sensor base, a sensor top cover, a resistivity measuring sample, a resistivity sample spacer, and a corrosion measuring sample; the sensor frame is a cylindrical structure, with the resistivity measuring sample, resistivity sample spacer, and corrosion measuring sample fitted onto the outside of the sensor frame; the sensor top cover is fixed to the front end of the sensor frame, and one end of the sensor base is threadedly connected to the rear end of the sensor frame to press the resistivity measuring sample, resistivity sample spacer, and corrosion measuring sample together; the other end of the sensor base is connected to a signal interface socket; the inner walls of both the resistivity measuring sample and the corrosion measuring sample are provided with wiring positioning posts, which extend into the sensor frame and are connected to the corresponding terminals of the signal interface socket via wires; the corrosion measuring sample is made of the same grade of metal as the reinforcing steel to be monitored.

[0008] In the reinforced concrete corrosion monitoring sensor of the present invention, the front end of the sensor frame is also provided with a temperature and humidity measuring element, each of which has a lead wire connected to a signal interface socket, and a water-proof and breathable membrane is provided between the sensor top cover and the sensor frame.

[0009] In the reinforced concrete corrosion monitoring sensor of the present invention, the sensor is provided with two resistivity measuring test pieces and two resistivity test piece spacers, which are alternately fitted on the outside of the sensor frame.

[0010] In the reinforced concrete corrosion monitoring sensor of the present invention, the sensor is provided with 4 corrosion measuring test pieces and 4 corrosion measuring test piece diaphragms, and the corrosion measuring test piece diaphragms and corrosion measuring test pieces are alternately sleeved on the outside of the sensor frame.

[0011] In the reinforced concrete corrosion monitoring sensor of the present invention, the outer wall of the sensor frame is provided with two first wiring positioning grooves and one second wiring positioning groove, both of which are arranged along the axial direction of the sensor frame; the two first wiring positioning grooves are symmetrically arranged, and the inner wall of the resistivity measuring test piece is symmetrically provided with two wiring positioning posts that extend into the sensor frame from the corresponding first wiring positioning grooves; the inner wall of the corrosion measuring test piece is provided with one wiring positioning post that extends into the sensor frame from the second wiring positioning groove.

[0012] In the reinforced concrete corrosion monitoring sensor of the present invention, a frustum is provided at the front end of the sensor frame, the diameter of the frustum is equal to the outer diameter of the corrosion measurement test piece, and the water-proof and breathable membrane is pasted on the end face of the frustum and covers the opening at the front end of the sensor frame.

[0013] In the reinforced concrete corrosion monitoring sensor of the present invention, an auxiliary installation structure is designed on the outer wall of the sensor base. The auxiliary installation structure cooperates with the installation clamp to clamp the reinforcing bar to be tested and fixes it with bolts.

[0014] In the reinforced concrete corrosion monitoring sensor of the present invention, the sensor frame, sensor base, sensor top cover, resistivity test piece spacer and corrosion measurement test piece diaphragm are all made of PE non-metallic corrosion-resistant material.

[0015] In the reinforced concrete corrosion monitoring sensor of the present invention, the resistivity measuring specimen is made of Pt metal material.

[0016] The reinforced concrete corrosion monitoring sensor of the present invention has at least the following beneficial effects:

[0017] 1. The reinforced concrete corrosion monitoring sensor of the present invention can meet the requirements of engineering applications. The sensor is pre-embedded and can monitor the corrosion of reinforced concrete throughout the entire life cycle of the reinforced concrete structure in real time.

[0018] 2. The reinforced concrete corrosion monitoring sensor of the present invention is a multifunctional sensor that can not only monitor the corrosion rate of steel bars, but also simultaneously monitor the service microenvironment information of steel bars related to corrosion, such as temperature, humidity and concrete resistivity, providing more comprehensive data for diagnosing the corrosion status of steel bars.

[0019] 3. The reinforced concrete corrosion monitoring sensor of the present invention uses corrosion-resistant and anti-aging non-metallic materials as the main body, and has the characteristics of small size, strong adaptability, long service life and convenient installation. Attached Figure Description

[0020] Figure 1 This is a structural diagram of a sensor for monitoring corrosion in reinforced concrete.

[0021] Figure 2 This is a cross-sectional view of a sensor for monitoring corrosion in reinforced concrete.

[0022] Figure 3 This is a structural diagram of the sensor skeleton;

[0023] Figure 4 This is a cross-sectional view of the sensor frame.

[0024] Figure 5 This is a structural diagram of the resistivity measurement specimen;

[0025] Figure 6 A structural diagram of the corrosion measurement specimen;

[0026] Figure 7 Installation structure diagram for reinforced concrete corrosion monitoring sensors;

[0027] 1-Sensor body, 2-Mounting clamp, 3-Fixing bolt, 4-Reinforcing bar, 101-Sensor frame, 102-Sensor base, 103-Resistivity measurement test piece, 104-Resistivity test piece spacer, 105-Corrosion measurement test piece, 106-Corrosion measurement test piece diaphragm, 107-Temperature and humidity measuring element, 108-Waterproof and breathable membrane, 109-Sensor top cover, 110-Wire, 111-Signal interface socket. Detailed Implementation

[0028] See attached document Figure 1-7 The structure of a reinforced concrete corrosion monitoring sensor of the present invention will be described in detail.

[0029] like Figure 1 As shown, the reinforced concrete corrosion monitoring sensor of the present invention consists of a sensor body 1, a mounting clamp 2, and bolts 3.

[0030] like Figure 2 As shown, the sensor body 1 includes: a sensor frame 101, a sensor base 102, a sensor top cover 109, a resistivity measuring test piece 103, a resistivity test piece spacer 104, and a corrosion measuring test piece 105; the sensor frame 101 has a cylindrical structure, and the resistivity measuring test piece 103, the resistivity test piece spacer 104, and the corrosion measuring test piece 105 are sleeved on the outside of the sensor frame 101; the sensor top cover 109 is fixed to the front end of the sensor frame 101, and one end of the sensor base 102 is connected to the sensor frame 109. The rear end of the sensor base 102 is connected by a thread to press the resistivity measuring test piece 103, the resistivity test piece spacer 104, and the corrosion measuring test piece 105 together. The other end of the sensor base 102 is connected to the signal interface socket 111. The inner walls of the resistivity measuring test piece 103 and the corrosion measuring test piece 105 are provided with wiring positioning posts. The wiring positioning posts extend into the interior of the sensor frame 101 and are connected to the corresponding terminals of the signal interface socket 111 through wires. The corrosion measuring test piece 105 is made of the same grade of metal material as the steel bar 4 to be monitored.

[0031] like Figure 2As shown, a temperature and humidity measuring element 107 is also provided at the front end of the sensor frame 101. The temperature and humidity measuring element 107 is a miniaturized sensing element that integrates the functions of measuring ambient temperature and humidity, and is located in the central cavity of the sensor frame 101. Each pin of the temperature and humidity measuring element 107 has a wire leading out to a signal interface socket 111. A water-proof and breathable diaphragm 108 is provided between the sensor top cover 109 and the sensor frame 101. The water-proof and breathable diaphragm 108 is a thin circular sheet made of water-proof and breathable material, which is used to prevent liquid media from entering the inner cavity of the sensor frame while allowing gaseous media in the environment to freely enter the inner cavity and contact the temperature and humidity measuring element 107, ensuring the accuracy of temperature and humidity measurement.

[0032] like Figure 3 and Figure 4 As shown, the outer wall of the sensor frame 101 is provided with two first wiring positioning grooves 1011 and one second wiring positioning groove 1012 for positioning the resistivity measuring test piece 103 and the corrosion measuring test piece 105. Both the first wiring positioning grooves 1011 and the second wiring positioning groove 1012 are arranged along the axial direction of the sensor frame 101. The two first wiring positioning grooves 1011 are symmetrically arranged. Two wiring positioning posts are symmetrically arranged on the inner wall of the resistivity measuring test piece 103 and extend into the sensor frame 101 from the corresponding first wiring positioning groove 1011. The inner wall of the corrosion measuring test piece 105 is provided with one wiring positioning post that extends into the sensor frame 101 from the second wiring positioning groove 1012. The front end of the sensor frame 101 is provided with a frustum 1013, the diameter of which is equal to the outer diameter of the corrosion measuring test piece 105. The water-proof and breathable membrane 108 is adhered to the end face of the frustum 1013 and covers the opening at the front end of the sensor frame 101.

[0033] Figure 5 This is a structural diagram of the resistivity measuring test piece 103. The resistivity measuring test piece 103 is preferably made of Pt metal material, which is corrosion-resistant and has good conductivity. The resistivity test piece spacer 104 is preferably made of PE non-metallic corrosion-resistant material; both are annular structures. In a specific implementation, the sensor has two resistivity measuring test pieces 103 and two resistivity test piece spacers 104. The resistivity measuring test pieces 103 and resistivity test piece spacers 104 are alternately fitted onto the outside of the sensor frame 101. Figure 2 As shown, the resistivity measuring test piece 103 and the resistivity test piece spacer 104 are arranged in an ABAB pattern, and one wire 110 is connected to the wiring positioning post of each resistivity measuring test piece 103. The wire 110 is preferably a single-core copper measuring wire with insulation. The other end of the wire is connected to the corresponding terminal of the signal interface socket 111.

[0034] Figure 6The diagram shows the structure of the corrosion measurement test piece 105. The corrosion measurement test piece diaphragm 106 is made of PE non-metallic corrosion-resistant material. Both the corrosion measurement test piece 105 and the corrosion measurement test piece diaphragm 106 are annular structures. In a specific implementation, the sensor has four corrosion measurement test pieces 105 and four corrosion measurement test piece diaphragms 106, which are alternately fitted onto the outside of the sensor frame 101. Figure 2 As shown, the corrosion measurement test piece 105 and the corrosion measurement test piece diaphragm 106 are arranged in an ABABABAB pattern, and a wire 110 is connected to the wiring positioning post of each corrosion measurement test piece 105. The other end of the wire is connected to the corresponding terminal of the signal interface socket 111.

[0035] An auxiliary installation structure is designed on the outer wall of the sensor base 102. The auxiliary installation structure cooperates with the installation clamp 2 to clamp the steel bar to be tested and fix it with bolts 3.

[0036] In practice, the sensor frame 101, sensor base 102, and sensor top cover 109 are all made of PE non-metallic corrosion-resistant material.

[0037] The reinforced concrete corrosion monitoring sensor of this invention needs to be used in conjunction with professional data acquisition and analysis equipment to monitor the corrosion rate of the reinforcing steel, the microenvironmental temperature and humidity of the reinforcing steel during service, and the resistivity of the concrete. An installation diagram is shown below. Figure 7 As shown, the sensor body 1 and the monitored rebar 4 are fixed together using an auxiliary installation structure and mounting clamps 2. Two fixing bolts 3 securely fasten the monitored rebar 4. After the sensor is connected to a dedicated cable via a signal interface socket 111, the entire sensor assembly is embedded in the concrete structure along with the monitored rebar, leaving only one end of the dedicated cable connected to the sensor exposed outside the concrete structure for connection to professional data acquisition and analysis equipment. The sensor assembly is pre-embedded near the rebar, and the corrosion rate of the rebar can be equivalently measured by measuring the corrosion rate of a corrosion measuring specimen 105 made of the same material as the rebar. The corrosion rate of the corrosion measuring specimen 105 is measured using a weakly polarized electrochemical method. The concrete resistivity is measured by applying voltage to two resistivity measuring specimens 103 at a known distance, measuring the current value, and the data acquisition and analysis equipment calculates the concrete resistivity using a computational model. Monitoring of the microenvironment temperature and humidity of the rebar during service is achieved by directly reading the temperature and humidity values ​​using temperature and humidity measuring elements built into the sensor.

[0038] The above description is only a preferred embodiment of the present invention and is not intended to limit the ideas of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A sensor for monitoring corrosion of reinforced concrete, characterized in that, include: The sensor assembly comprises a sensor frame, a sensor base, a sensor top cover, a resistivity measuring sample, a resistivity sample spacer, and a corrosion measuring sample. The sensor frame is a cylindrical structure, with the resistivity measuring sample, resistivity sample spacer, and corrosion measuring sample fitted onto the outside of the sensor frame. The sensor top cover is fixed to the front end of the sensor frame. One end of the sensor base is threaded to the rear end of the sensor frame to press the resistivity measuring sample, resistivity sample spacer, and corrosion measuring sample together. The other end of the sensor base is connected to a signal interface socket. The inner walls of both the resistivity measuring sample and the corrosion measuring sample are equipped with wiring positioning posts that extend into the sensor frame and are connected to the corresponding terminals of the signal interface socket via wires. The corrosion measuring sample is made of the same grade of metal as the steel bar being monitored. The sensor frame is also equipped with a temperature and humidity measuring element at the front end of the internal part. Each of its pins has a wire leading out to the signal interface socket. A water-proof and breathable membrane is provided between the sensor top cover and the sensor frame. The sensor is equipped with two resistivity measuring test pieces and two resistivity test piece spacers, which are alternately fitted onto the outside of the sensor frame. The sensor is equipped with four corrosion measurement test pieces and four corrosion measurement test piece diaphragms, with the corrosion measurement test piece diaphragms and corrosion measurement test pieces alternately fitted onto the outside of the sensor frame; The outer wall of the sensor frame is provided with two first wiring positioning slots and one second wiring positioning slot, both of which are arranged along the axial direction of the sensor frame; the two first wiring positioning slots are symmetrically arranged, and the inner wall of the resistivity measurement test piece is symmetrically provided with two wiring positioning posts that extend into the sensor frame from the corresponding first wiring positioning slots; the inner wall of the corrosion measurement test piece is provided with one wiring positioning post that extends into the sensor frame from the second wiring positioning slot. The front end of the sensor frame is provided with a frustum, the diameter of which is equal to the outer diameter of the corrosion measurement test piece. The water-proof and breathable membrane is pasted on the end face of the frustum and covers the opening at the front end of the sensor frame. The sensor is embedded near the reinforcing steel. The corrosion rate of the steel is equivalent to that of the reinforcing steel by measuring the corrosion rate of a corrosion measuring specimen made of the same material as the steel. The corrosion rate of the corrosion measuring specimen is measured using a weakly polarized electrochemical method. A voltage is applied to two resistivity measuring specimens with a known spacing, and the current value is measured. The data acquisition and analysis equipment calculates the concrete resistivity through a calculation model.

2. The reinforced concrete corrosion monitoring sensor as described in claim 1, characterized in that, The sensor base has an auxiliary installation structure on its outer wall. The auxiliary installation structure works with the installation clamp to hold the steel bar to be tested and is fixed with bolts.

3. The reinforced concrete corrosion monitoring sensor as described in claim 2, characterized in that, The sensor frame, sensor base, sensor top cover, resistivity test piece spacer, and corrosion measurement test piece diaphragm are all made of PE non-metallic corrosion-resistant material.

4. The reinforced concrete corrosion monitoring sensor as described in claim 1, characterized in that, The resistivity measurement test piece is made of Pt metal material.

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