Concrete carbonization depth prediction method, system and equipment
By constructing a concrete carbonization depth prediction model containing two fitting parameters, the problem of low accuracy of the Fick model is solved, and more accurate concrete carbonization depth prediction is achieved, which improves the scientific nature of structural maintenance and safety assessment.
Patent Information
- Application Number
- CN202510051687.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-13
- Publication Date
- 2025-05-13
AI Technical Summary
The existing Fick model has low accuracy when predicting the carbonization depth of concrete, making it difficult to accurately describe the development laws of concrete carbonization depth.
By measuring the carbonization depth at different moments of the concrete structure, a concrete carbonization depth prediction model equation containing two fitted parameters is constructed, and the fitted parameter values are solved using a system of linear equations to form a curved equation for predicting the carbonization depth, and then the carbonization depth at any moment is predicted.
Compared with the existing Fick model, this method can more accurately predict the carbonization depth of concrete, significantly improve the prediction accuracy, and provide more scientific technical support for the maintenance and safety assessment of concrete structures.
Smart Images
Figure CN119993313A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of concrete carbonization prediction, and more particularly to a method, system and device for predicting the depth of concrete carbonization. Background Art
[0002] Concrete carbonation refers to the process in which carbon dioxide in the air reacts chemically with calcium hydroxide in concrete in the presence of water to produce calcium carbonate and water. Concrete carbonation will reduce the alkalinity of concrete, thereby weakening the protective effect on the steel bars. When the carbonation depth of concrete reaches a certain threshold, damage such as steel bar corrosion and concrete cracks will occur, shortening the service life of the concrete structure. Accurately predicting the carbonation depth of concrete is of great significance for structural safety assessment and prevention of steel bar corrosion, ensuring the safe use of the structure.
[0003] At present, the most commonly used mathematical model for predicting concrete carbonization is the Fick model, and its formula is as follows:
[0004]
[0005] Among them, C represents the carbonation depth of concrete, t represents time, and a represents the fitting parameter, which needs to be obtained through curve fitting based on some experimental data. However, since the Fick model only contains one fitting parameter, the curve equation obtained after fitting is often not accurate enough to predict the carbonation depth of concrete in the later stage.
[0006] Therefore, how to provide a method, system and device for predicting the carbonization depth of concrete that can solve the above problems is an issue that technical personnel in this field urgently need to solve. Summary of the invention
[0007] In view of this, the present invention provides a method, system and device for predicting the carbonation depth of concrete, which can more accurately predict the carbonation depth of concrete to better guide subsequent concrete maintenance and safety assessment work.
[0008] In order to achieve the above object, the present invention provides the following technical solutions:
[0009] A method for predicting concrete carbonization depth, comprising:
[0010] For the concrete structure to be evaluated, measure the carbonation depth of concrete at different times;
[0011] Construct concrete carbonation depth prediction model equation;
[0012] Substituting the data of the concrete carbonization depth measured at different times into the concrete carbonization depth prediction model equation, and combining the concrete carbonization depth prediction model equation to obtain a linear equation system;
[0013] Solve the linear equations to obtain the fitting parameter values;
[0014] Substitute the fitting parameter values into the concrete carbonization depth prediction model equation to obtain the curve equation for carbonization depth prediction;
[0015] The curve equation is used to predict the carbonization depth at any time.
[0016] Preferably, for the concrete structure to be evaluated, measuring the carbonation depth of concrete at different times includes:
[0017] For the concrete structure to be evaluated, measure n different times t1, t2, …, t n The carbonization depth of concrete is respectively
[0018] Preferably, the constructed concrete carbonization depth prediction model equation is expressed as:
[0019]
[0020] Among them, C represents the carbonation depth of concrete, t represents time, e represents the natural constant, and a and b represent two fitting parameters.
[0021] Preferably, the data of the concrete carbonization depth measured at different times are substituted into the concrete carbonization depth prediction model equation, and the concrete carbonization depth prediction model equation is combined to obtain a linear equation system:
[0022] y = Θ·x;
[0023] in
[0024]
[0025] Where C represents the carbonation depth of concrete, t represents time, e represents a natural constant, a and b represent two fitting parameters, and y represents t1, t2, …, t n The column vector is composed of the square values of the carbonization depth at the moment, Θ represents the coefficient matrix of the linear equations, and x represents the column vector composed of the fitting parameters.
[0026] Preferably, the linear equations are solved to obtain the fitting parameter values, and the solution formula is:
[0027] x=(Θ T Θ) -1 Θ T y;
[0028] Where y represents t1, t2, …, t nThe column vector of the square value of the carbonization depth at the time, Θ represents the coefficient matrix of the linear equations, x represents the column vector composed of the fitting parameters, Θ T represents the transposed matrix of matrix Θ, and the calculated set parameter value is recorded as and
[0029] Preferably, the fitting parameter value is substituted into the concrete carbonization depth prediction model equation to obtain the curve equation for carbonization depth prediction:
[0030]
[0031] In the formula, C represents the carbonation depth of concrete, t represents time, and e represents a natural constant. and represents two fitting parameter values.
[0032] Preferably, the carbonization depth at any time is predicted using a curve equation, including:
[0033] Set time t z Substituting into the curve equation:
[0034]
[0035] In the formula, is the calculated carbonization depth, t z For any moment.
[0036] A concrete carbonization depth prediction system, comprising:
[0037] The measurement module measures the carbonation depth of concrete at different times for the concrete structure to be evaluated;
[0038] Model building module, building concrete carbonation depth prediction model equation;
[0039] The model combination module substitutes the data of the concrete carbonization depth measured at different times into the concrete carbonization depth prediction model equation, and combines the concrete carbonization depth prediction model equation to obtain a linear equation group;
[0040] The calculation module solves the linear equations to obtain the fitting parameter values;
[0041] The parameter substitution module substitutes the fitting parameter value into the concrete carbonization depth prediction model equation to obtain the curve equation for carbonization depth prediction;
[0042] The prediction module uses the curve equation to predict the carbonization depth at any moment.
[0043] An electronic device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein a method for predicting the carbonation depth of concrete is implemented when the processor executes the computer program.
[0044] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a method, system and equipment for predicting the carbonation depth of concrete. By continuously accumulating data and optimizing models, more mature and reliable prediction methods and standards can be formed, providing more scientific and systematic technical support for various links such as the design, construction and maintenance of concrete structures. The new model for predicting the carbonation depth of concrete proposed by the present invention can make up for the defects of the single curve of the Fick model, and can more accurately predict the carbonation depth of concrete, so as to better guide subsequent concrete maintenance and safety assessment work. BRIEF DESCRIPTION OF THE DRAWINGS
[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in 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 only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.
[0046] Figure 1 It is a schematic diagram of the method flow of the present invention;
[0047] Figure 2 It is a schematic diagram of the system structure of the present invention. DETAILED DESCRIPTION
[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.
[0049] The purpose of the present invention is to provide a method, system and equipment for predicting the carbonation depth of concrete, comprising: measuring the carbonation depth of concrete at different times for a concrete structure to be evaluated; constructing a concrete carbonation depth prediction model equation; substituting the data of the measured concrete carbonation depth at different times into the concrete carbonation depth prediction model equation, and combining the concrete carbonation depth prediction model equation to obtain a linear equation group; solving the linear equation group to obtain fitting parameter values; substituting the fitting parameter values into the concrete carbonation depth prediction model equation to obtain a curve equation for predicting the carbonation depth; using the curve equation to predict the carbonation depth at any time, so as to provide a solution for more accurately predicting the concrete carbonation depth.
[0050] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.
[0051] Embodiment 1:
[0052] See also Figure 1 The embodiment of the present invention discloses a method for predicting the carbonization depth of concrete, comprising:
[0053] For the concrete structure to be evaluated, measure the carbonation depth of concrete at different times;
[0054] Construct concrete carbonation depth prediction model equation;
[0055] Substituting the data of the concrete carbonization depth measured at different times into the concrete carbonization depth prediction model equation, and combining the concrete carbonization depth prediction model equation to obtain a linear equation system;
[0056] Solve the linear equations to obtain the fitting parameter values;
[0057] Substitute the fitting parameter values into the concrete carbonization depth prediction model equation to obtain the curve equation for carbonization depth prediction;
[0058] The curve equation is used to predict the carbonization depth at any time.
[0059] In a specific embodiment, a new model for predicting the carbonation depth of concrete is as follows:
[0060]
[0061] Among them, C represents the carbonation depth of concrete, t represents time, e represents the natural constant, and a and b represent two fitting parameters, which need to be obtained through curve fitting based on part of the experimental data.
[0062] In a specific embodiment, the concrete carbonization depth prediction implementation method specifically includes:
[0063] First, the conventional phenolphthalein indicator method (the specific operation steps of this method are shown in the Standard for Test Methods for Long-term Performance and Durability of Ordinary Concrete (GB / T 50082-2009)) is used to measure the concrete structure to be evaluated at n (n≥3) different times t1, t2, …, t n The carbonization depth of concrete is respectively
[0064] Then, the concrete carbonation depth data obtained at n different times are substituted into the new model equation (2), and these n equations are combined to obtain the following linear equation system:
[0065] y = Θ·x (3);
[0066] in:
[0067]
[0068]
[0069]
[0070] Solve equation (3) to obtain the specific value of the fitting parameter. The solution formula is:
[0071] x=(Θ T Θ) -1 Θ T y (7);
[0072] where Θ T represents the transposed matrix of matrix Θ, which is a common operation in matrix operations. The specific values of the parameters a and b (denoted as and ), and substituting it into equation (2), we can obtain the specific curve equation for carbonization depth prediction:
[0073]
[0074] Finally, equation (8) can be used to predict at any time t z Carbonization depth That is, time t z Substituting into equation (8) we get:
[0075]
[0076] The carbonization depth calculated by equation (9) is It can be used to guide subsequent concrete maintenance and safety assessment work.
[0077] In a specific embodiment, due to the numerous factors that affect the carbonation of concrete, the development law of the carbonation depth of concrete is very complicated. The existing Fick model is a single curve function, so it is difficult to accurately describe the development law of the carbonation depth of concrete. The new concrete carbonation depth prediction model proposed in the present invention introduces a new curve term To make up for the defect of the single curve of the Fick model, this new curve term has the following mathematical characteristics:
[0078] When t = 0, When t→∞, Therefore, this newly added curve term is a bounded function in the interval [0,1), which can be regarded as a reasonable correction of the deviation of the development law of concrete carbonization depth from the Fick model law in actual engineering.
[0079] The first-order derivative of this new curve term with respect to time t is The second-order derivative with respect to time t is Therefore, this newly added curve term is a convex function, which is consistent with the characteristic that the carbonation depth of concrete in actual engineering develops according to a convex function.
[0080] See also Figure 2 The embodiment of the present invention discloses a concrete carbonization depth prediction system, comprising:
[0081] The measurement module measures the carbonation depth of concrete at different times for the concrete structure to be evaluated;
[0082] Model building module, building concrete carbonation depth prediction model equation;
[0083] The model combination module substitutes the data of the concrete carbonization depth measured at different times into the concrete carbonization depth prediction model equation, and combines the concrete carbonization depth prediction model equation to obtain a linear equation group;
[0084] The calculation module solves the linear equations to obtain the fitting parameter values;
[0085] The parameter substitution module substitutes the fitting parameter value into the concrete carbonization depth prediction model equation to obtain the curve equation for carbonization depth prediction;
[0086] The prediction module uses the curve equation to predict the carbonization depth at any moment.
[0087] On the other hand, an embodiment of the present invention discloses an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned concrete carbonization depth prediction method when executing the computer program.
[0088] It can be seen from the above technical solutions that, compared with the prior art, the present invention has the following beneficial effects: the present invention provides a new model for predicting the carbonation depth of concrete and an implementation method thereof, which can predict the carbonation depth of concrete more accurately than the existing Fick model.
[0089] Embodiment 2:
[0090] Based on the concrete carbonation depth test data (for specific test data, see: Zhang Xuhui, Liu Bowen, Yang Ling, et al., Experimental study on concrete carbonation performance under different temperatures and strengths, Building Structure), the following verifies that the concrete carbonation depth prediction method, system and equipment provided by the present invention can more accurately predict the concrete carbonation depth, so as to better guide the subsequent concrete maintenance and safety assessment work.
[0091] Specifically, the conventional phenolphthalein indicator method was used to test the carbonation depth of concrete specimens at 3, 7, 14, 28, 56, and 84 days, and the corresponding carbonation depth data obtained from the test were as follows: 9.6mm, 14.6mm, 17.03mm, 24.95mm, 34.1mm, and 41.4mm. The experimental data at the first five moments were used for curve fitting, and the experimental data at the last 84 days were used to verify the accuracy of model prediction.
[0092] In a specific embodiment, the concrete carbonization depth prediction implementation method is as follows:
[0093] First, the conventional phenolphthalein indicator method (the specific operation steps of this method are shown in the Standard for Test Methods for Long-term Performance and Durability of Ordinary Concrete (GB / T 50082-2009)) is used to measure the concrete structure to be evaluated at n (n≥3) different times t1, t2, …, t n The carbonization depth of concrete is respectively
[0094] For this embodiment, at time t1=3, t2=7, t3=14, t4=28, t5=56, the carbonization depths of concrete are respectively
[0095] Then, the concrete carbonation depth data obtained at n different times are substituted into the new model equation (2), and these n equations are combined to obtain the following linear equation system:
[0096] y = Θ·x (3);
[0097] in:
[0098]
[0099]
[0100]
[0101] Solve equation (3) to obtain the specific value of the fitting parameter. The solution formula is:
[0102] x=(Θ T Θ) -1 ΘT y (7);
[0103] where Θ T represents the transposed matrix of matrix Θ, which is a common operation in matrix operations. The specific values of the parameters a and b (denoted as and ), for this embodiment, the specific values of the calculated parameters a and b are and
[0104] Substituting into equation (2), the specific curve equation for carbonization depth prediction can be obtained as follows:
[0105]
[0106] For this embodiment, the specific curve equation for carbonization depth prediction is:
[0107]
[0108] Finally, equation (8-2) can be used to predict at any time t z Carbonization depth For this example, in order to compare with the experimental value, t z =84. z =84Substituting into equation (8-2) we get:
[0109]
[0110] Therefore, the carbonation depth of concrete on the 84th day in this embodiment predicted by the new model proposed in the present invention is 41.5758 mm, which is very close to the true value of 41.4 mm obtained by actual experimental test, with an error of only 0.1758 mm.
[0111] If the existing Fick model is used, for this embodiment, the concrete carbonation depth predicted on the 84th day according to the above implementation method is 42.9557mm, and the error between it and the actual value of 41.4mm obtained by the actual experimental test is 1.5557mm. Obviously, the prediction error of the new concrete carbonation depth prediction model provided by the present invention is only 11.3% of the prediction error of the existing Fick model, and the prediction accuracy is significantly improved.
[0112] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.
[0113] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A method for predicting the carbonation depth of concrete, characterized in that: include: For the concrete structure to be evaluated, measure the carbonation depth of concrete at different times; Construct concrete carbonation depth prediction model equation; Substituting the data of the concrete carbonization depth measured at different times into the concrete carbonization depth prediction model equation, and combining the concrete carbonization depth prediction model equation to obtain a linear equation system; Solve the linear equations to obtain the fitting parameter values; Substitute the fitting parameter values into the concrete carbonization depth prediction model equation to obtain the curve equation for carbonization depth prediction; The curve equation is used to predict the carbonization depth at any time.
2. A method for predicting concrete carbonization depth according to claim 1, characterized in that: For the concrete structure to be evaluated, the carbonation depth of concrete at different times is measured including: For the concrete structure to be evaluated, measure n different times t1, t2, …, t n The carbonization depth of concrete is respectively 3. A method for predicting carbonization depth of concrete according to claim 1, characterized in that: The constructed concrete carbonization depth prediction model equation is expressed as: Among them, C represents the carbonation depth of concrete, t represents time, e represents the natural constant, and a and b represent two fitting parameters.
4. A method for predicting carbonization depth of concrete according to claim 1, characterized in that: Substitute the data of concrete carbonization depth measured at different times into the concrete carbonization depth prediction model equation, and combine the concrete carbonization depth prediction model equation to obtain the linear equation system: y = Θ·x; in Where C represents the carbonation depth of concrete, t represents time, e represents a natural constant, a and b represent two fitting parameters, and y represents t1, t2, …, t n The column vector is composed of the square values of the carbonization depth at the moment, Θ represents the coefficient matrix of the linear equations, and x represents the column vector composed of the fitting parameters.
5. A method for predicting carbonization depth of concrete according to claim 1, characterized in that: Solve the linear equations to obtain the fitting parameter values. The solution formula is: x=(Θ T I) -1 I T ·y; Where y represents t1, t2, …, t n The column vector of the square value of the carbonization depth at the time, Θ represents the coefficient matrix of the linear equations, x represents the column vector composed of the fitting parameters, Θ T represents the transposed matrix of matrix Θ, and the calculated set parameter value is recorded as and 6. A method for predicting carbonization depth of concrete according to claim 1, characterized in that: Substituting the fitting parameter values into the concrete carbonization depth prediction model equation, the curve equation for carbonization depth prediction is obtained as follows: In the formula, C represents the carbonation depth of concrete, t represents time, and e represents a natural constant. and represents two fitting parameter values.
7. A method for predicting carbonization depth of concrete according to claim 1, characterized in that: The carbonation depth at any time is predicted using the curve equation, including: Set time t z Substituting into the curve equation: In the formula, is the calculated carbonization depth, t z For any moment.
8. A concrete carbonization depth prediction system using the concrete carbonization depth prediction method according to any one of claims 1 to 7, characterized in that: include: The measurement module measures the carbonation depth of concrete at different times for the concrete structure to be evaluated; Model building module, building concrete carbonation depth prediction model equation; The model combination module substitutes the data of the concrete carbonization depth measured at different times into the concrete carbonization depth prediction model equation, and combines the concrete carbonization depth prediction model equation to obtain a linear equation group; The calculation module solves the linear equations to obtain the fitting parameter values; The parameter substitution module substitutes the fitting parameter value into the concrete carbonization depth prediction model equation to obtain the curve equation for carbonization depth prediction; The prediction module uses the curve equation to predict the carbonization depth at any moment.
9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method for predicting the carbonization depth of concrete according to any one of claims 1 to 7 is implemented.