Temperature correction method of chloride ion sensor

Abstract

The invention discloses a temperature correction method of a chloride ion sensor, which comprises the following steps of: S1, arranging a micro array type chloride ion sensor of a pre-embedded concrete protective layer in an array mode, and determining an acquisition scheme; s2, carrying out anomaly detection on a MnO2 reference electrode in the micro array chloride ion sensor; s3, correcting an acquired potential value of the micro array type chloride ion sensor; s4, according to the Nernst potential-concentration logarithm linear relation, determining various coefficients of the standard equation under the control temperature in the concrete; and S5, determining a temperature compensation coefficient according to the Nernst potential-concentration logarithm linear relationship. And S6, calculating the concentration distribution condition of chloride ions at different depths in the concrete by using the sensor potential after temperature compensation. According to the invention, the influence of temperature on the measurement result of the chloride ion sensor can be effectively compensated, the potential abnormal interference in the measurement process of the sensor is effectively overcome, and the precision and reliability of the sensor are improved.

Description

Technical Field

[0001] The invention belongs to a temperature correction method, in particular to a temperature correction method for a chloride ion sensor. Background Art

[0002] During long-term service, marine engineering concrete is corroded by corrosive substances such as chloride ions in the external environment, which leads to steel corrosion and reduced concrete strength, thus affecting its durability and structural safety. Chloride ions are one of the most important factors affecting concrete corrosion. Therefore, real-time monitoring of the distribution and evolution of chloride ion concentration inside concrete is of great significance for effective evaluation and early warning of the durability and safety of concrete structures.

[0003] Traditional methods for detecting chloride ions mainly include on-site core sampling + chemical titration, ion chromatography, resistivity method and electrochemical non-destructive monitoring methods. Among them, electrochemical non-destructive detection of chloride ion concentration in concrete mainly detects chloride ion concentration in concrete by embedding chloride ion sensors, which mainly include selective electrodes sensitive to chloride ions and reference electrodes that provide stable reference potential. Compared with other traditional detection methods, chloride ion sensors have the characteristics of non-destructive, real-time, high efficiency and accuracy, and have been gradually applied to real-time monitoring of chloride ions in concrete. However, existing chloride ion sensors are greatly affected by temperature changes, and the arrangement of multiple probes of array sensors will greatly increase the detection error caused by temperature, further affecting the timely and effective evaluation and protection of concrete structure corrosion. Summary of the invention

[0004] Purpose of the invention: In order to overcome the deficiencies in the prior art, the purpose of the present invention is to provide a temperature calibration method for a chloride ion sensor with high detection accuracy and reliability.

[0005] Technical solution: A temperature calibration method for a chloride ion sensor according to the present invention comprises the following steps:

[0006] S1. Micro array chloride ion sensors embedded in the concrete protective layer are arranged in array and the collection scheme is determined;

[0007] S2, abnormal detection of MnO2 reference electrode in micro array chloride ion sensor;

[0008] S3, correction of potential value collected by micro array chloride ion sensor;

[0009] S4. Determine the coefficients of the standard equation for controlling the temperature in concrete based on the Nernst potential-concentration logarithmic linear relationship;

[0010] S5. Determine the temperature compensation coefficient based on the Nernst potential-concentration logarithmic linear relationship.

[0011] S6. The distribution of chloride ion concentration at different depths in concrete is obtained by calculating the temperature-compensated sensor potential.

[0012] Furthermore, in step S1, the micro array chloride ion sensor includes a wire, a temperature sensor, a MnO2 reference electrode, an Ag / AgCl selective electrode and an insulating protective filling material. The Ag / AgCl selective electrode is arranged in multiple layers, and a reference electrode is arranged at the center of each layer of the Ag / AgCl selective electrode. The Ag / AgCl selective electrode, the MnO2 reference electrode and the temperature sensor are connected to the wire through a PCB board, and the wire is connected to an external mobile device.

[0013] Furthermore, the working interface at the front end of the Ag / AgCl selective electrode is inclined at an angle of 50 to 60 degrees to the horizontal plane.

[0014] Furthermore, in step S1, the acquisition scheme is: using MnO2 reference electrodes in pairs to form a detection circuit, recording the open circuit potential matrix between the MnO2 reference electrodes The time series data of the Ag / AgCl selection electrode and the adjacent MnO2 reference electrode potential acquisition circuit is formed by equidistant measurement to collect the sensor potential matrix E Ag / AgCl Time series data of

[0015]

[0016] Among them, E RiRj It represents the time series of the open circuit potential between the reference electrode Ri and the reference electrode Rj at different times, Ri is connected to the positive terminal, and Rj is connected to the negative terminal;

[0017]

[0018] Among them, E SiRj It represents the time series of the open circuit potential between the selected electrode Si and the reference electrode Rj at different times.

[0019] Furthermore, in step S2, the abnormality detection is to calculate the potential fluctuation value of each independent MnO2 reference electrode according to the potential time series data between each MnO2 reference electrode in the open circuit potential matrix between MnO2 reference electrodes. If it is greater than 30mV, the reference electrode is judged to be abnormal.

[0020] Furthermore, step S3 is specifically as follows: based on the abnormal detection result of the MnO2 reference electrode, the average potential of the remaining qualified reference electrodes after removing the abnormal electrodes is used as the unified reference potential of the sensor, and the collected sensor potential matrix is ​​adjusted to the sensor potential with the unified reference potential as a reference.

[0021] Further, step S4 includes the following steps:

[0022] S41. Calculate the coefficients of the Nernst equation at the controlled temperature T0. Embed the sensor in concrete with a calibrated chloride concentration of c = [c1, c2, ...cn] mol / L and wait for the potential to reach equilibrium. Place the sensor in a constant temperature device at the controlled temperature T0 to obtain the sensor potential matrix E. According to the Nernst potential-concentration logarithmic linear relationship, use linear regression to fit E and lg[c] to obtain the control potential matrix E. 0 with the Nernst slope matrix Where R is the ideal gas constant, which is 8.314 J / (mol·K), n is the number of electron transfers, and F is the Faraday constant, which is approximately 96485 C / mol;

[0023] S42, outlier cleaning, according to the 3σ principle, calculate E 0 and the mean of k and standard deviation σ k , traverse each point of the sensor to determine (i=1,2,…16) are outliers. After removing the outliers, the coefficient matrix is ​​calculated and the average value is taken. Substitute the Nernst standard equation at the formation control temperature

[0024] Furthermore, the Nernst potential-concentration logarithmic linear relationship is

[0025]

[0026] Where E is the sensor potential matrix, E 0 is the control potential matrix, R is the ideal gas constant, its value is 8.314 J / (mol·K), n is the number of electron transfers, F is the Faraday constant, its value is about 96485 C / mol, T0 is the control temperature, and c is the calibration chloride salt concentration.

[0027] Further, S5 includes the following steps:

[0028] S51. Use the sensor potential matrix to perform temperature compensation and determine the temperature-corrected Nernst potential-concentration response relationship: E comp =E+α(T-T0), where E comp is the correction potential, α is the temperature compensation coefficient, T is the real-time temperature, and T0 is the control temperature;

[0029] S52, based on the correction potential E comp According to the Nernst standard equation, we can get By actually measuring the linear relationship between E and T, the temperature compensation coefficient α is obtained by fitting, where E is the sensor potential matrix, For E0 The mean value, E 0 is the control potential matrix, is the mean of k, k is the Nernst slope matrix, and c is the calibration chloride concentration.

[0030] Further, step S6 includes the following steps:

[0031] Step S61, calculating a calibration potential matrix according to the sensor potential matrix E obtained from the concrete in which the sensor is actually embedded, the real-time temperature T collected by the temperature sensor and the temperature-corrected Nernst potential-concentration response relationship;

[0032] Step S62, search and eliminate abnormal potentials layer by layer, and use the average potential after elimination as the representative value of the potential of each layer. If there are 4 abnormal values ​​in the traversed layer, take the average of the two potentials closest to the representative value of the potential measured in the previous layer as the representative value of the potential of the layer, and transform it according to the standard temperature Nernst equation to calculate the chloride ion concentration matrix of different layers;

[0033] Step S63: According to the concentration conversion formula Calculate the chloride ion mass fraction c of each layer of concrete ％ , where c layer is the chloride ion concentration matrix of different layers, M Cl is the relative atomic mass of chlorine, S is the degree of saturation, φ s is the porosity of concrete, ρ c is the density of concrete.

[0034] Beneficial effects: Compared with the prior art, the present invention has the following significant features: the proposed temperature correction method for a micro-array chloride ion sensor for detecting chloride ions in concrete based on the Nernst potential-concentration logarithmic linear relationship first corrects the potential matrix of the sensor by detecting the abnormality of the reference electrode potential, then obtains the standard Nernst equation expression by controlling the temperature based on the Nernst potential-concentration logarithmic linear relationship, further obtains the sensor potential temperature compensation parameter by adjusting the temperature by fixing the concentration, and then obtains the sensor potential data after temperature compensation, and finally calculates the chloride ion concentration distribution at each selected electrode of the sensor after temperature correction by the above standard Nernst equation expression; it can effectively compensate for the influence of temperature on the measurement result of the chloride ion sensor, effectively overcome the abnormal potential interference in the sensor's own measurement process, improve the accuracy and reliability of the sensor, and provide effective support for non-destructive detection of chloride ions in concrete structures and providing structural damage warning. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a flow chart of the present invention;

[0036] Figure 2 It is a structural schematic diagram of the micro array chloride ion sensor of the present invention;

[0037] Figure 3 It is a connection diagram of the MnO2 reference electrode 3 and the Ag / AgCl selection electrode 4 of the present invention. DETAILED DESCRIPTION

[0038] A temperature correction method for a chloride ion sensor comprises the following steps:

[0039] S1. The micro array chloride ion sensor embedded in the concrete protective layer is arranged in an array, and the collection plan is determined according to the arrangement form.

[0040] The specific layout of the array chloride ion sensor used is as follows: Figure 2-3 As shown, the main components are: Ag / AgCl selective electrodes 4 distributed in a 4×4 array, MnO2 reference electrodes 3 distributed in a 2×2 array, temperature sensors 2, wires 1 and insulating protective filling materials 5. Wire 1 is connected to external acquisition and communication equipment, and insulating protective filling materials 5 wrap the selective electrodes, reference electrodes, and temperature sensors to prevent them from being interfered with by the outside world. The sensor considers that different layers of Ag / AgCl selective electrodes 4 are arranged in the direction of vertical invasion of chloride ions. In order to detect the chloride ion concentration at different depths in concrete and predict the chloride ion diffusion, 4 layers of Ag / AgCl selective electrodes 4 are evenly arranged. Each layer is set with 4 Ag / AgCl selective electrodes 4 to effectively solve the failure of some Ag / AgCl selective electrodes 4. In order to prevent the upper electrode from affecting the diffusion of chloride ions to the lower electrode, the front end of each layer of selective electrodes ensures that the working interface is at a 60° inclination angle with the horizontal plane. In order to reduce the influence of the paths of the Ag / AgCl selective electrodes 4 and the MnO2 reference electrodes 3 on the measurement results, the MnO2 reference electrodes 3 are arranged in an array to ensure that each MnO2 reference electrode 3 has the same path from the adjacent 4 Ag / AgCl selective electrodes 4. The detection end of each layer of the Ag / AgCl selective electrode 4 extends 7mm from the sensor working interface, and the contact end of the MnO2 reference electrode 3 is flush with the working interface. The rear side of the sensor is connected to the Ag / AgCl selective electrode 4, the MnO2 reference electrode 3 and the temperature sensor 2 using a PCB board.

[0041] The half-cell loop acquisition scheme is based on the spatial arrangement of the sensor electrodes in step S1. The MnO2 reference electrode 3 is an important component that provides a stable potential reference and plays an important role in accurately evaluating the chloride ion concentration in concrete. The MnO2 reference electrode 3 has a long-term potential stability of less than 10mV / year. Based on this feature, the abnormal reference electrode is determined by mutual inspection of the reference electrode potential, and the MnO2 reference electrodes 3 are paired to form an acquisition loop to collect the open circuit potential matrix between the MnO2 reference electrodes 3. The Ag / AgCl selective electrode 4 is affected by the chloride ion concentration, resulting in the electrode reaction potential and the chloride ion concentration showing a Nernst relationship. The Ag / AgCl selective electrode 4 and the adjacent MnO2 reference electrode 3 form a sensor potential acquisition circuit to acquire the sensor potential matrix E. Ag / AgCl During the collection process, the mutual electric field interference between different collection channels can be avoided by collecting them one by one. Each collection needs to achieve potential balance and a group potential collection can be performed.

[0042] The collection plan specifically includes:

[0043] Step S11, using MnO2 reference electrodes 3 in pairs to form a detection circuit, recording the open circuit potential matrix between the MnO2 reference electrodes 3 Time series data:

[0044]

[0045] Where E RiRj Represented at different times t1, t2, …t n The open circuit potential time series between the lower reference electrode Ri and the reference electrode Rj, Ri is connected to the positive terminal, and Rj is connected to the negative terminal. According to the characteristics of the open circuit potential, the acquisition circuit selects the upper right half of the potential matrix for acquisition, and the lower left corner is selected according to E ij =-E ji Sure.

[0046] Step S12, using equidistant measurement to form a potential acquisition circuit between the Ag / AgCl selection electrode 4 and the adjacent MnO2 reference electrode 3, and collecting the sensor potential matrix E Ag / AgCl Time series data:

[0047]

[0048] Where E SiRj Represented at different times t1, t2, …t n The open circuit potential timing series between the lower selected electrode Si and the reference electrode Rj.

[0049] S2. Abnormal detection of MnO2 reference electrode 3 in micro array chloride ion sensor. According to the open circuit potential matrix between reference electrodes The potential time series data E between the reference electrodes RiRj , calculate the independent reference electrode potential fluctuation e R , the calculation process mainly includes the following steps:

[0050] Step S21, determine the overall potential fluctuation of the two electrodes: RiRj The data variance of the time series after potential equilibrium represents the overall potential fluctuation of the two reference electrodes. RiRjThe potential equilibrium time can be determined by long-term observation of the potential fluctuation of the MnO2 reference electrode 3, and the maximum time required for the MnO2 reference electrode buried in concrete to reach equilibrium except for the obviously failed electrode is determined by batch tests as the reference electrode potential equilibrium time of the method of the present invention;

[0051] Step S22, according to the error propagation law, the independent variable error is equivalent to the potential fluctuation of the independent reference electrode, and the relationship between the overall volatility and the potential fluctuation of each independent reference electrode is determined: RiRj =e Ri +e Rj +Δ i_j , where e Ri With e Rj is the potential fluctuation of reference electrodes Ri and Rj, Δ i_j For accidental fluctuations in the measurement process;

[0052] Step S23, determining the potential fluctuation value e of each independent reference electrode R :Based on the principle that the random error of time series data gradually decreases over time, the overall random error S is defined as the objective function, the overall random error is minimized, and constraint conditions are established to calculate the potential fluctuation value of each independent reference electrode:

[0053]

[0054] The least squares method is used to solve the partial derivatives as zero:

[0055]

[0056] Obtain the potential fluctuation value e of each independent reference electrode R =[e R1 ,e R2 ,e R3 ,e R4 ], according to the provisions of 4.3 of GB / T 7387-1999 Technical Specifications for Marine Reference Electrodes, the potential stability of the reference electrode is ±15mV, that is, the potential fluctuation is 30mV. Ri >30mV means that the MnO2 reference electrode 3 is abnormal.

[0057] S3, micro array type chloride ion sensor acquisition potential value correction. Using the abnormal detection result of the MnO2 reference electrode 3 in step S23, the average potential of the remaining qualified MnO2 reference electrodes 3 after removing the abnormal electrodes is used as the sensor unified reference potential, and the potential matrix E collected in step S12 is converted into Ag / AgCl Adjust to a uniform reference potential. The main method is: Correct the sensor potential E = E Ag / AgCl +Δ:

[0058]

[0059] in It is the potential difference from the reference electrode Ri potential to the sensor unified reference potential. Although the abnormal MnO2 reference electrode 3 cannot provide long-term reference electrode function, due to the record of the mutual potential between the MnO2 reference electrodes 3, the potential of the 4 Ag / AgCl selective electrodes 4 corresponding to the abnormal reference can be converted to the unified reference potential through potential transfer. Therefore, the correction to the unified reference potential is divided into two categories:

[0060] If Ri is a normal MnO2 reference electrode 3, then:

[0061]

[0062] Among them, U is the number set of normal MnO2 reference electrode 3, is the ordinal sequence E in step S11 RiRj The equilibrium potential, n is the number of normal MnO2 reference electrodes 3;

[0063] If Ri is an abnormal MnO2 reference electrode 3, then:

[0064]

[0065] Among them, E RiRj It is the potential value of the open circuit potential time series between the electrode Si and the reference Rj at the calculation moment selected in step S11.

[0066] S4. Determine the coefficients of the standard equation at the control temperature in concrete based on the Nernst potential-concentration logarithmic linear relationship.

[0067] S41, calculate the coefficients of the Nernst equation at the controlled temperature T0. The sensor is buried in concrete with a calibrated chloride concentration of c = [c1, c2, ...cn] mol / L, and the potential is balanced. The sensor is placed in a constant temperature device at the controlled temperature T0 to obtain the sensor potential matrix E. According to the Nernst principle Use linear regression to fit E and lg[c] to obtain the control potential matrix E 0 with the Nernst slope matrix R is the ideal gas constant, whose value is 8.314 J / (mol·K), n is the number of electron transfers, and F is the Faraday constant, whose value is approximately 96485 C / mol.

[0068] S42, outlier cleaning. According to the 3σ principle, calculate E 0 and the mean of k and standard deviation σ k , traverse each point of the sensor to determine (i=1,2,…16) are outliers. After removing the outliers, the coefficient matrix is ​​calculated and the average value is taken. Substitute the Nernst standard equation at the formation control temperature

[0069] S5. Determine the coefficients of the temperature compensation equation in concrete based on the Nernst potential-concentration logarithmic linear relationship. The sensor is fixedly embedded in the chloride ion concentration c of the concrete, and the temperature is gradually increased to ensure that the overall temperature of the sensor reaches Ti (i = 1, 2, ... n, and the number of calibration temperatures n can be determined based on experiments). The temperature can refer to the temperature change in the concrete use environment in one year, and the corrected sensor potential matrix E used in step S3 of the present invention is calculated to determine the coefficients in the Nernst potential-concentration relationship using temperature correction. The specific method includes:

[0070] S51, performing temperature compensation according to the corrected sensor potential E used in step S3, and determining the temperature-corrected Nernst potential-concentration response relationship: E comp =E+α(T-T0), where E comp is the correction potential, α is the temperature compensation coefficient, and T is the real-time temperature;

[0071] S52, calculate the temperature compensation coefficient α, based on the correction potential E comp It complies with the Nernst standard equation in step S41 of the present invention. Right now:

[0072]

[0073] It is deduced that:

[0074]

[0075] The temperature compensation coefficient α is obtained by fitting the linear relationship between the actual measurement E and T. Where E is the sensor potential matrix, For E 0 The mean of is the mean value of k, and c is the calibration chloride salt concentration.

[0076] S6. Calculate the distribution of chloride ion concentration at different depths in actual concrete using the temperature-compensated sensor potential.

[0077] S61, calculate the calibration potential matrix based on the measured potential. Obtain the corrected sensor potential matrix E according to step S31 of the present invention based on the concrete in which the sensor is actually embedded, and the real-time temperature T collected by the temperature sensor, combined with the temperature-corrected Nernst potential-concentration response relationship E in step S51. comp=E+α(T-T0) to calculate the calibration potential matrix:

[0078]

[0079] S62, calculate the chloride ion concentration of different layers. According to the abnormal value cleaning method described in step S42 of the present invention, search and remove abnormal potentials layer by layer, and use the average potential after removal as the representative value of the potential of each layer If there are 4 abnormal values ​​in the traversed layer, the average of the two potentials closest to the potential representative value of the layer measured last time is taken as the potential representative value of the layer. Transformation E layer replace The chloride ion concentration matrix of different layers is calculated: c layer =[c layer1 c layer2 c layer3 c layer4 ].

[0080] S63, based on the concentration conversion formula Calculate the chloride ion mass fraction of each layer of concrete. Cl is the relative atomic mass of chlorine, S is the degree of saturation, φ s is the porosity of concrete, ρ c is the density of concrete.

Claims

1. A temperature correction method for a chloride ion sensor, characterized in that: The following steps are involved: S1. Micro array chloride ion sensors embedded in the concrete protective layer are arranged in array and the collection scheme is determined; S2, abnormality detection of MnO2 reference electrode (3) in micro array chloride ion sensor; S3, correction of potential value collected by micro array chloride ion sensor; S4. Determine the coefficients of the standard equation for controlling the temperature in concrete based on the Nernst potential-concentration logarithmic linear relationship; S5. Determine the temperature compensation coefficient based on the Nernst potential-concentration logarithmic linear relationship. S6. The distribution of chloride ion concentration at different depths in concrete is obtained by calculating the temperature-compensated sensor potential.

2. The temperature calibration method of a chloride ion sensor according to claim 1, characterized in that: In the step S1, the micro array type chloride ion sensor comprises a wire (1), a temperature sensor (2), a MnO2 reference electrode (3), an Ag / AgCl selective electrode (4) and an insulating protective filling material (5); the Ag / AgCl selective electrode (4) is arranged in multiple layers, and a reference electrode (3) is arranged at the center of each layer of the Ag / AgCl selective electrode (4); the Ag / AgCl selective electrode (4), the MnO2 reference electrode (3) and the temperature sensor (2) are connected to the wire (1) via a PCB board, and the wire (1) is connected to an external mobile device.

3. The temperature correction method of a chloride ion sensor according to claim 2, characterized in that: The working interface at the front end of the Ag / AgCl selection electrode (4) is inclined at an angle of 50 to 60 degrees with the horizontal plane.

4. The temperature calibration method of a chloride ion sensor according to claim 2, characterized in that: In step S1, the acquisition scheme is: using MnO2 reference electrodes (3) in pairs to form a detection circuit, and recording the open circuit potential matrix between the MnO2 reference electrodes (3) The time series data of the Ag / AgCl selection electrode (4) and the adjacent MnO2 reference electrode (3) are formed by equidistant measurement to collect the potential matrix E of the sensor. Ag / AgCl Time series data of Among them, E RiRj It represents the time series of the open circuit potential between the reference electrode Ri and the reference electrode Rj at different times, Ri is connected to the positive terminal, and Rj is connected to the negative terminal; Among them, E SiRj It represents the time series of the open circuit potential between the selected electrode Si and the reference electrode Rj at different times.

5. The temperature calibration method of a chloride ion sensor according to claim 1, characterized in that: In the step S2, the abnormality detection is to calculate the potential fluctuation value of each independent MnO2 reference electrode (3) based on the potential time series data between each MnO2 reference electrode (3) in the open circuit potential matrix between the MnO2 reference electrodes (3). If it is greater than 30mV, it is determined that the reference electrode is abnormal.

6. The temperature calibration method of a chloride ion sensor according to claim 1, characterized in that: Specifically, step S3 comprises: according to the abnormal detection result of the MnO2 reference electrode (3), the average potential of the remaining qualified reference electrodes after removing the abnormal electrode is used as the unified reference potential of the sensor, and the collected sensor potential matrix is ​​adjusted to the sensor potential with the unified reference potential as a reference.

7. The temperature calibration method of a chloride ion sensor according to claim 1, characterized in that: The step S4 comprises the following steps: S41. Calculate the coefficients of the Nernst equation at the controlled temperature T0, bury the sensor in concrete with a calibrated chloride concentration of c = [c1, c2, ...cn] mol / L, wait for the potential to reach equilibrium, place it in a constant temperature device at the controlled temperature T0, obtain the sensor potential matrix E, and use linear regression to fit E and lg[c] based on the Nernst potential-concentration logarithmic linear relationship to obtain the control potential matrix E 0 with the Nernst slope matrix Where R is the ideal gas constant, which is 8.314 J / (mol·K), n is the number of electron transfers, and F is the Faraday constant, which is approximately 96485 C / mol; S42, outlier cleaning, according to the 3σ principle, calculate E 0 and the mean of k and standard deviation σ k , traverse each point of the sensor to determine (i=1,2,...16) are outliers. After removing the outliers, the coefficient matrix is ​​calculated and the average value is taken. Substitute the Nemst standard equation at the formation control temperature 8. The temperature calibration method of a chloride ion sensor according to claim 1, characterized in that: The Nernst potential-concentration logarithmic linear relationship is: Where E is the sensor potential matrix, E 0 is the control potential matrix, R is the ideal gas constant, its value is 8.314 J / (mol·K), n is the number of electron transfers, F is the Faraday constant, its value is about 96485 C / mol, T0 is the control temperature, and c is the calibration chloride salt concentration.

9. The temperature calibration method of a chloride ion sensor according to claim 1, characterized in that: The step S5 comprises the following steps: S51. Use the sensor potential matrix to perform temperature compensation and determine the temperature-corrected Nernst potential-concentration response relationship: E comp =E+α(T-T0), where E comp is the correction potential, α is the temperature compensation coefficient, T is the real-time temperature, and T0 is the control temperature; S52, based on the correction potential E comp According to the Nernst standard equation, we can get By actually measuring the linear relationship between E and T, the temperature compensation coefficient α is obtained by fitting, where E is the sensor potential matrix, For E 0 The mean value, E 0 is the control potential matrix, is the mean of k, k is the Nernst slope matrix, and c is the calibration chloride concentration.

10. The temperature calibration method of a chloride ion sensor according to claim 1, characterized in that: The step S6 comprises the following steps: Step S61, calculating a calibration potential matrix according to the sensor potential matrix E obtained from the concrete in which the sensor is actually embedded, the real-time temperature T collected by the temperature sensor and the temperature-corrected Nernst potential-concentration response relationship; Step S62, search and eliminate abnormal potentials layer by layer, and use the average potential after elimination as the representative value of the potential of each layer. If there are 4 abnormal values ​​in the traversed layer, take the average of the two potentials closest to the representative value of the potential measured in the previous layer as the representative value of the potential of the layer, and transform it according to the standard temperature Nernst equation to calculate the chloride ion concentration matrix of different layers; Step S63: According to the concentration conversion formula Calculate the chloride ion mass fraction c of each layer of concrete ％ , where c layer is the chloride ion concentration matrix of different layers, M Cl is the relative atomic mass of chlorine, S is the degree of saturation, φ s is the porosity of concrete, ρ c is the density of concrete.

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