Intelligent maintenance method and system driven by sensing of temperature and humidity fields in concrete

Abstract

The invention discloses an intelligent curing method and system driven by sensing of an internal temperature and humidity field of concrete. The intelligent curing method comprises the following steps that the surface tensile strength and the elastic modulus of the concrete of the same concrete mix proportion and different ages are obtained; according to the concrete maturity theory and the concrete surface tensile strength of different ages, a fitting function of the concrete surface tensile strength is obtained; predicting a fitting function through the elastic moduli of different ages and the elastic moduli; obtaining the inner surface control temperature difference of the concrete at different ages by utilizing the relationship between the concrete surface tensile strength and the concrete surface tensile stress and combining the fitting function of the concrete surface tensile strength and the elastic modulus prediction fitting function; and the concrete curing environment temperature and humidity are intelligently controlled according to the inner surface control temperature difference of the concrete of different ages. By dynamically determining the concrete curing temperature control index and combining with the humidity requirement, the on-off of the curing equipment is controlled, and the temperature and humidity of the concrete curing environment are intelligently controlled.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete curing, and particularly to an intelligent curing method and system driven by the perception of the internal temperature and humidity field of concrete. Background Art

[0002] With the continuous expansion of the scale of highway tunnel construction, the growth rate of tunnel projects has exceeded the overall development level of the highway network. However, in the existing tunnels, there are common diseases such as water leakage and lining cracking, which seriously threaten the safety and service life of the tunnel structure. In order to improve the quality of tunnel projects, concrete curing technology has become a key link. At present, the curing of tunnel lining concrete mainly controls the curing temperature according to the specified requirements with preset fixed target values.

[0003] However, this traditional curing technology has the defects of not considering the stage characteristics of concrete hydration reaction and being unable to match the dynamic law of concrete strength development. The demand for curing temperature of concrete is different in different hydration stages, and the fixed temperature control mode cannot meet this demand. On the other hand, as the strength of concrete increases, its ability to resist cracking also gradually increases. The fixed temperature control mode cannot be adjusted according to the actual situation of concrete strength development, resulting in the coexistence of excessive early temperature stress and late energy waste. Summary of the Invention

[0004] The purpose of the present invention is to provide an intelligent curing method and system driven by the perception of the internal temperature and humidity field of concrete, which solves the problems of lack of dynamic control, low automation degree and insufficient control accuracy in the existing concrete curing control.

[0005] To achieve this purpose, an intelligent curing method driven by the perception of the internal temperature and humidity field of concrete designed by the present invention is carried out according to the following steps:

[0006] Obtain the surface tensile strength of concrete and the elastic modulus of concrete at different ages under the same concrete mix through experiments;

[0007] Based on the concrete maturity theory, obtain the fitting function of the surface tensile strength of concrete according to the surface tensile strength of concrete at different ages;

[0008] Predict the fitting function of the elastic modulus through the elastic modulus at different ages;

[0009] According to the safety factor, establish the relationship between the surface tensile strength of concrete and the surface tensile stress of concrete at different ages. According to this relationship and in combination with the fitting function of the surface tensile strength of concrete and the predicted fitting function of the elastic modulus, obtain the internal and surface control temperature difference of concrete at different ages;

[0010] Intelligently control the curing environment temperature of concrete by controlling the internal and surface temperature difference of concrete at different ages.

[0011] According to an intelligent curing method driven by the perception of the internal temperature and humidity field of concrete provided by the present invention, the test settings for obtaining the surface tensile strength of concrete and the elastic modulus of concrete at different ages with the same concrete mix ratio include:

[0012] By setting the surface tensile strength tests of concrete under several different concrete mix ratios, respectively obtain the surface tensile strength of concrete at different ages with the same concrete mix ratio;

[0013] By setting the elastic modulus test of concrete, obtain the elastic modulus of concrete at different ages.

[0014] According to an intelligent curing method driven by the perception of the internal temperature and humidity field of concrete provided by the present invention, the method for obtaining the fitting function of the surface tensile strength of concrete is:

[0015] According to the test data acquisition module, obtain the surface tensile strength of concrete and the measured value of the internal temperature of concrete at different ages with the same concrete mix ratio, and use the concrete maturity theory formula to fit the tensile strength curve of concrete, obtain the regression coefficients a, b and the fitting function of the surface tensile strength of concrete at different ages, and perform fitting according to the following formula:

[0016]

[0017] M = ∑(T + 15)×Δt;

[0018] Where, f s (t) is the surface tensile strength of concrete at age t, M represents the concrete curing maturity, T is the average value of the measured internal temperature of concrete per unit time, the unit can be taken as 1 hour, and Δt represents the time interval.

[0019] According to an intelligent curing method driven by the perception of the internal temperature and humidity field of concrete provided by the present invention, the method for obtaining the predicted fitting function of the elastic modulus is:

[0020] According to the elastic modulus of concrete at different ages, use the following formula for function fitting, fit the elastic modulus growth rate coefficient c, and obtain the predicted fitting function of the elastic modulus, and perform fitting according to the following formula:

[0021] E(t) = E 0 +E 1 (1 - e -ct ) ;

[0022] Where, E(t) is the elastic modulus of concrete at age t (MPa), E 0is the elastic modulus (MPa) at the final setting of concrete, E 1 is the elastic modulus at 28 days under standard curing, and c is the elastic modulus growth rate coefficient.

[0023] According to an intelligent curing method driven by the perception of the internal temperature and humidity field of concrete provided by the present invention, the method for establishing the relationship between the tensile strength of the concrete surface at different ages and the tensile stress on the concrete surface layer is as follows:

[0024] Set the safety factor β, then the relationship between the tensile strength f s (t) of the concrete surface at age t and the tensile stress on the concrete surface layer at age t is:

[0025] f s (t) ≥ β·σ s (t);

[0026] where σ s (t) is the tensile stress on the concrete surface layer (MPa) at age t;

[0027] Obtain the formula for σ s (t), and the formula is:

[0028]

[0029] where α is the coefficient of linear expansion of concrete (℃ -1 ), E(t) is the elastic modulus of concrete at age t (MPa), ΔT ab (t) is the internal and surface controlled temperature difference of concrete at age t (℃), and K P represents the stress relaxation coefficient caused by concrete creep.

[0030] According to an intelligent curing method driven by the perception of the internal temperature and humidity field of concrete provided by the present invention, the method for obtaining the internal and surface controlled temperature difference of concrete at different ages is as follows:

[0031] Set the coefficient of linear expansion α of concrete and the stress relaxation coefficient K caused by concrete creep P ;

[0032] Combined with the fitting function f s (t) of the tensile strength of the concrete surface at different ages and the predicted fitting function E(t) of the elastic modulus, obtain the internal and surface controlled temperature difference ΔT ab (t) of concrete at different ages.

[0033] According to an intelligent curing method driven by the perception of the internal temperature and humidity field of concrete provided by the present invention, the intelligent control of the temperature and humidity of the concrete curing environment by using the internal and surface controlled temperature difference of concrete at different ages: According to the internal and surface controlled temperature difference ΔT ab(t) and the humidity requirements for concrete curing, generate temperature and humidity curing instructions and transmit them to the intelligent curing device. The wireless receiving and control device of the intelligent curing device receives the temperature and humidity curing instructions, and the intelligent curing device controls the heating device and the humidifying device to execute the instructions.

[0034] The present invention also provides an intelligent curing system driven by the perception of the internal temperature and humidity field of concrete. The system operates according to an intelligent curing method driven by the perception of the internal temperature and humidity field of concrete, including:

[0035] An experimental data acquisition module, which is used to obtain the concrete surface tensile strength and the elastic modulus of concrete at different ages with the same concrete mix ratio through experiments;

[0036] A tensile strength fitting module, which is used to obtain the fitting function of the concrete surface tensile strength based on the concrete maturity theory, according to the measured value of the internal temperature of the concrete and the concrete surface tensile strength at different ages;

[0037] An elastic modulus fitting module, which is used to obtain the predicted fitting function of the elastic modulus through the elastic modulus of concrete at different ages;

[0038] A temperature control index acquisition module, which is used to establish the relationship between the concrete surface tensile strength and the tensile stress on the concrete surface layer at different ages according to the safety factor, and according to the relationship between the concrete surface tensile strength and the tensile stress on the concrete surface layer at different ages, combined with the fitting function of the concrete surface tensile strength and the fitting function of the concrete surface tensile strength, obtain the internal and surface control temperature difference of concrete at different ages;

[0039] An intelligent control module, which uses the internal and surface control temperature difference of concrete at different ages to intelligently control the temperature of the concrete curing environment.

[0040] According to an intelligent curing system driven by the perception of the internal temperature and humidity field of concrete provided by the present invention, the experimental data acquisition module includes:

[0041] A concrete surface tensile strength acquisition module, which obtains the concrete surface tensile strength at different ages with the same concrete mix ratio by setting a number of concrete surface tensile strength tests under different concrete mix ratios;

[0042] A concrete elastic modulus acquisition module, which obtains the elastic modulus of concrete at different ages by setting the elastic modulus test of concrete.

[0043] An intelligent curing system driven by the perception of the temperature and humidity field inside concrete provided by the present invention. The tensile strength fitting module obtains the elastic modulus of concrete at different ages according to test data, and performs function fitting using the following formula to fit the elastic modulus growth rate coefficient c and obtain the elastic modulus prediction fitting function. The fitting is carried out according to the following formula:

[0044] E(t) = E 0 + E 1 (1 - e -ct );

[0045] where E(t) is the elastic modulus of concrete at age t (MPa), E 0 is the elastic modulus of concrete at the end of final setting (MPa), E 1 is the elastic modulus at 28d under standard curing, and c is the elastic modulus growth rate coefficient.

[0046] The beneficial effects of the present invention are as follows:

[0047] 1) By obtaining the change curves of the tensile strength and elastic modulus of different types of concrete through tests, establishing a concrete performance database and performance prediction curves, the actual performance of concrete can be predicted more accurately, ensuring the safety and durability of the structure.

[0048] 2) The intelligent control module can adjust the temperature of the curing environment according to the actual situation of the concrete, providing the best hydration reaction conditions for the concrete, thereby improving its quality and reducing defects.

[0049] 3) The intelligent control module can automatically adjust the curing equipment according to needs, avoiding unnecessary energy consumption and reducing operating costs.

[0050] 4) Through the real-time monitoring and accurate prediction of the concrete performance, the internal and surface control temperature difference of concrete at different ages is obtained, and the concrete is dynamically cured, effectively reducing the risk of concrete cracking, reducing the energy consumption of concrete curing, improving the curing quality, and accelerating the overall construction speed.

[0051] 5) The temperature control index acquisition module can obtain the internal and surface control temperature difference of concrete at different ages, preventing problems such as concrete cracking caused by excessive temperature difference, and ensuring the safe use of the building. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 is the flow chart of the intelligent curing system driven by the perception of the temperature and humidity field of concrete of the present invention;

[0053] Figure 2 is the schematic diagram of the internal and surface temperature difference of concrete in the embodiment of the present invention;

[0054] Figure 3Example diagram allowing inner surface function in the embodiments of the present invention;

[0055] Figure 4 Fitting curve diagram of tensile strength in the embodiments of the present invention;

[0056] Figure 5 Fitting curve diagram of elastic modulus in the embodiments of the present invention;

[0057] Figure 6 Variation diagram of the maximum allowable inner surface temperature difference of concrete with the increase of age in the embodiments of the present invention. Detailed implementation manners

[0058] The embodiments of the present invention will be described in detail below, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0059] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

[0060] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0061] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0062] The present invention provides an intelligent curing method and a corresponding system driven by the perception of the internal temperature and humidity field of concrete. The intelligent curing method of the internal temperature and humidity field perception of concrete in the present invention obtains the surface tensile strength and elastic modulus of concrete with the same concrete mix ratio at different ages through experiments. Based on the concrete maturity theory and combined with the experimental data, the fitting function of the concrete surface tensile strength and the predicted fitting function of the elastic modulus are obtained. Then, according to the relationship between the surface tensile strength of concrete at different ages and the tensile stress on the concrete surface layer, and combined with the fitting function of the concrete surface tensile strength and the predicted fitting function of the elastic modulus, the internal and surface control temperature difference of concrete at different ages is obtained. By obtaining the internal and surface control temperature difference of concrete at different ages, the maximum allowable temperature difference between the inside and the surface of concrete at different ages is determined, and the intelligent control of the curing environment temperature of concrete is realized by controlling the on-off of the curing equipment. Compared with the traditional concrete curing control that uses a fixed target value for temperature control, the present invention can dynamically adjust the temperature control requirements for concrete curing according to the internal and surface control temperature difference of concrete at different ages obtained by the intelligent curing method driven by the perception of the internal temperature and humidity field of concrete as the concrete strength dynamically increases, which can significantly improve the construction quality and efficiency, and promote the refined management and sustainable development of the construction industry.

[0063] Example 1:

[0064] As Figures 1 to 6 shown, an intelligent curing method driven by the perception of the internal temperature and humidity field of concrete is carried out according to the following steps:

[0065] Obtain the surface tensile strength and elastic modulus of concrete with the same concrete mix ratio at different ages through experiments;

[0066] By setting multiple groups of experiments on the surface tensile strength and elastic modulus of concrete, systematic tests are carried out on concrete with different mix ratios and ages, and its mechanical property data can be accurately obtained. This not only helps to establish a more accurate strength and modulus prediction model, improve the safety and economy of engineering design, but also can optimize the concrete mix ratio to ensure the construction quality.

[0067] Based on the concrete maturity theory, according to the measured value of the internal temperature of concrete and the surface tensile strength of concrete at different ages, obtain the fitting function of the concrete surface tensile strength;

[0068] The measured values of the surface tensile strength and internal temperature of concrete with the same mix ratio at different ages are analyzed using the concrete maturity theory formula. The curve of the tensile strength varying with time is fitted, and the regression coefficient and fitting function are obtained. This process enables us to accurately predict the tensile strength of concrete at any age, optimize the construction plan, and adjust the curing conditions in a timely manner. At the same time, the fitting function based on scientific data provides a reliable basis for engineering design, improving the safety and durability of the structure. In addition, it helps to reduce rework caused by insufficient strength, save costs, speed up the project progress, and provide valuable data support for the research on concrete performance.

[0069] Through the elastic modulus at different ages, the fitting function for elastic modulus prediction;

[0070] The elastic modulus of concrete at different ages obtained by the test data acquisition module is used to calculate the function fitting coefficient using the fitting formula, thereby obtaining the fitting function for elastic modulus prediction. This method can accurately predict the elastic modulus of concrete at any age, optimize the structural design and construction plan, and ensure the project quality and safety. At the same time, it provides a scientific basis for adjusting the curing measures, avoiding structural problems caused by insufficient modulus, and improving the project efficiency and economy.

[0071] According to the safety factor, the relationship between the surface tensile strength of concrete at different ages and the tensile stress on the concrete surface layer is established. Based on this relationship and combined with the fitting function of the surface tensile strength of concrete and the fitting function for elastic modulus prediction, the internal and surface temperature difference of concrete at different ages is obtained;

[0072] The above process utilizes the relationship between the surface tensile strength of concrete at different ages and the tensile stress on the concrete surface layer, sets an appropriate safety factor, establishes a connection between the surface tensile strength of concrete and the tensile stress on the concrete surface layer, and can accurately evaluate the tensile performance of concrete at different ages using the fitting value of the surface tensile strength of concrete and the calculation formula of the tensile stress on the concrete surface layer. It is convenient to obtain the internal and surface temperature difference of concrete at different ages, optimize the curing strategy, prevent defects such as cracks, improve the project quality, and provide a scientific basis for engineering design.

[0073] The intelligent control of the curing environment temperature of concrete is carried out using the internal and surface temperature difference of concrete at different ages.

[0074] The above process realizes the automated management of the curing environment temperature, which not only saves energy, reduces costs, but also improves the hardening quality of concrete and speeds up the construction progress.

[0075] Currently, the main control is on the internal and surface temperatures of concrete. In this embodiment, the concrete humidity is controlled at not less than 90% RH.

[0076] In some embodiments of the present invention, this embodiment optimizes the above test settings. The test settings for obtaining the tensile strength of the concrete surface and the elastic modulus of the concrete at different ages with the same concrete mix ratio include:

[0077] By setting the tensile strength tests of the concrete surface under several groups of different concrete mix ratios, the tensile strength of the concrete surface at different ages with the same concrete mix ratio is obtained respectively;

[0078] By setting the elastic modulus test of the concrete, the elastic modulus of the concrete at different ages is obtained.

[0079] In this embodiment, four groups of C35 lining concrete mix ratios can be set, and each group includes the tensile strength at 3d, 7d, and 56d; four groups of C40 lining concrete mix ratios are set, and each group includes the tensile strength at 3d, 7d, and 56d, as shown in Table 1.

[0080] Table 1 Tensile strength of C35 - C40

[0081]

[0082] In some embodiments of the present invention, this embodiment optimizes the fitting of the above tensile strength of the concrete surface. The method for the fitting function of the tensile strength of the concrete surface is:

[0083] According to the obtained tensile strength of the concrete surface at different ages with the same concrete mix ratio and the measured values of the internal temperature of the concrete, using the concrete maturity theory formula, the tensile strength curve of the concrete is fitted to obtain the regression coefficients a, b, and the fitting function of the tensile strength of the concrete surface at different ages. The specific formula is:

[0084]

[0085] M = ∑(T + 15)×Δt;

[0086] where, f s (t) is the tensile strength of the concrete surface at age t, M represents the curing maturity of the concrete, T is the average value of the measured internal temperature of the concrete per unit time, where the unit time can be taken as 1 hour, and Δt represents the time interval.

[0087] In this embodiment, according to the measured value of the internal temperature of the concrete, the average value of the internal temperature of the concrete per hour is calculated. The amount of the hydration reaction of the concrete is characterized by the cumulative value of the heat, and the average value T per unit time of the measured value of the internal temperature of the concrete is obtained. In the actual process, the change of the internal temperature of the concrete is relatively small, and the change amount per hour is usually within 1 °C. Therefore, during actual measurement, the measurement interval of the temperature sensor is usually set to one hour or less than one hour. Therefore, in practical applications, the measured value can represent the average temperature of the corresponding interval, that is, the average value T per unit time of the measured value of the internal temperature of the concrete. Thus, the curing maturity M of the concrete is obtained, combined with the tensile strength of the concrete surface. Therefore, t represents day, and using and the data in Table 1 for fitting, the fitted values of the regression coefficients a and b are obtained. The goodness-of-fit calculation is performed on each group of fitted values, as shown in Table 2. Among them, r represents the goodness-of-fit, and the closer it is to 1, the better the conformity of the formula with the measured data in Table 1. The fitting curve of the tensile strength of the concrete surface is as Figure 4 shown.

[0088] Table 2 Regression coefficients and goodness-of-fit

[0089]

[0090]

[0091] In some embodiments of the present invention, this embodiment optimizes the fitting of the above elastic modulus prediction. The method for obtaining the elastic modulus prediction fitting function is as follows:

[0092] According to the elastic modulus of concrete at different ages, function fitting is performed using the following formula to fit the elastic modulus growth rate coefficient c, and the elastic modulus prediction fitting function is obtained. The formula is:

[0093] E(t) = E 0 + E 1 (1 - e -ct );

[0094] Among them, E(t) is the elastic modulus of concrete at age t (MPa), E 0 is the elastic modulus of concrete at the end of setting (MPa), E 1 is the elastic modulus at 28 d under standard curing, and c is the elastic modulus growth rate coefficient.

[0095] In this embodiment, E 1 is the elastic modulus at 28 days, taking 30 GPa. The elastic modulus E 0 (MPa) of the concrete at the end of setting is determined by experiments, and c is the elastic modulus growth rate coefficient, which is determined by experiments.

[0096] As shown in Table 3, by fitting Table 3, we obtain E(t) = 6×10 9 + 2.8×10 10 (1 - e -0.54576t ), where the goodness of fit is 0.81, and the fitting curve is as shown in Figure 5 .

[0097] Table 3 Test data of elastic modulus of concrete

[0098] Age Elastic modulus Age Elastic modulus θ.1 6.43E+09 1.8906 2.33E+10 0.12776 7.80E+09 2.4153 2.44E+10 0.16322 9.25E+09 3.0858 2.54E+10 0.20852 1.08E+10 3.9423 2.63E+10 0.2664 1.23E+10 5.0365 2.71E+10 0.34034 1.38E+10 6.4344 2.78E+10 0.43481 1.54E+10 8.2204 2.85E+10 0.5555 1.68E+10 10.502 2.91E+10 0.70968 1.83E+10 13.417 2.97E+10 0.90666 1.97E+10 17.141 3.02E+10 1.1583 2.10E+10 21.899 3.06E+10 1.4798 2.22E+10 27.977 3.10E+10

[0099] In some embodiments of the present invention, this embodiment optimizes the establishment of the relationship between the surface tensile strength of concrete at different ages and the tensile stress on the concrete surface layer. The method for establishing the relationship between the surface tensile strength of concrete at different ages and the tensile stress on the concrete surface layer is as follows:

[0100] Set the safety factor β, then the relationship between the surface tensile strength f s (t) of concrete at age t and the tensile stress on the concrete surface layer at age t is:

[0101] f s (t) ≥ β·σ s (t);

[0102] where σ s (t) is the tensile stress on the concrete surface layer at age t (MPa), and the specific formula for σ s (t) is:

[0103]

[0104] where α is the coefficient of linear expansion of concrete (℃ -1 ), which can be taken as (1.0×10 -5 )℃ -1 , E(t) is the elastic modulus of concrete at age t (MPa), ΔT ab (t) is the temperature difference between the inner and outer surfaces of concrete at age t (℃), and K P represents the stress relaxation coefficient caused by concrete creep, which is determined by experiments and can be taken as 0.5 when there is no experimental data.

[0105] As shown in Figure 2 , T C is the highest temperature of the concrete core, T E is the temperature of the concrete surface, and T cure is the temperature difference between the inner and outer surfaces of the concrete. Due to the temperature difference between the inner and outer surfaces, tensile stress is generated. When the tensile stress is greater than the tensile strength of the concrete, the concrete cracks. Therefore, a safety factor is set to establish the relationship between the surface tensile strength of concrete at different ages and the tensile stress on the concrete surface layer.

[0106] In this embodiment, the safety factor is taken as 1.3, and the relationship between the tensile strength of the concrete surface at different ages and the tensile stress on the concrete surface layer is f s (t) ≥ 1.3σ s (t).

[0107] In some embodiments of the present invention, this embodiment optimizes the acquisition of the internal and surface control temperature difference of the above-mentioned concrete at different ages. The specific method for obtaining the internal and surface control temperature difference of concrete at different ages is as follows:

[0108] Set the expansion coefficient α of the concrete and the stress relaxation coefficient K caused by concrete creep P , combined with the fitting function f of the tensile strength of the concrete surface at different ages s (t) and the elastic modulus prediction fitting function E(t), obtain the internal and surface control temperature difference ΔT ab (t).

[0109] Figure 3 Figure 1 is an example diagram of the allowable internal and surface temperature difference function value changing with time. As the temperature changes, the function value of the allowable internal and surface temperature difference function is also constantly changing.

[0110] According to the above relationship between the tensile strength of the concrete surface at different ages and the tensile stress on the concrete surface layer, we can obtain:

[0111]

[0112] Among them, ΔT ab (t) max represents the allowable internal and surface temperature difference function, and ΔT ab (t) max is a function of t, and ΔT ab (t) ≤ ΔT ab (t) max .

[0113] Set α and K P , α = 1×10 (-5) , K P = 0.5, and through the fitting function f of the tensile strength of the concrete surface obtained by the above steps s (t), the elastic modulus prediction fitting function E(t), take ΔT ab (t) = ΔT ab (t) max , obtain the internal and surface control temperature difference ΔT of concrete at different ages ab (t), that is, the maximum allowable temperature difference on the concrete surface, as shown in Figure 6 .

[0114] In some embodiments of the present invention, this embodiment optimizes the intelligent control of the curing environment temperature of the above-mentioned concrete. The intelligent control of the temperature and humidity of the concrete curing environment is realized by using the internal and surface control temperature difference of concrete at different ages: according to the internal and surface control temperature difference ΔT ab (t) of concrete at different ages and the humidity requirement for concrete curing, a temperature and humidity curing instruction is generated and transmitted to the intelligent curing device. The wireless receiving and controlling device of the intelligent curing device receives the temperature and humidity curing instruction, and the intelligent curing device controls the heating device and the humidifying device to execute the instruction. Among them, the humidity requirement for concrete curing is that the humidity is not less than 90%RH.

[0115] The intelligent curing machine mainly includes a heating device, a humidifying device and a wireless receiving and controlling device, and has the following specific functions:

[0116] The heating device forms warm air at a certain temperature by heating the air and passes it into the curing area to increase the temperature of the curing area;

[0117] The humidifying device uses an ultrasonic atomizing device to turn normal temperature water into water mist with very small particle size. It has high atomization efficiency and less water consumption, which can ensure the humidity of the curing area and prevent phenomena such as water accumulation and icing;

[0118] The wireless receiving and controlling device can receive the instructions sent by the control system in real time, and the automatic control device controls the heating device and the humidifying device according to the instructions, so that the temperature and humidity of the curing area and the internal and surface temperature difference of the concrete are maintained within the range of the design requirements.

[0119] In addition, the present invention also provides an intelligent curing system driven by the perception of the internal temperature and humidity field of concrete. The intelligent curing system of the present invention performs intelligent curing according to the above-mentioned intelligent curing method driven by the perception of the internal temperature and humidity field of concrete, and specifically includes: an experimental data acquisition module, a tensile strength fitting module, an elastic modulus fitting module, a temperature control index acquisition module and an intelligent control module; the experimental data acquisition module is used to obtain the surface tensile strength and elastic modulus of concrete with the same concrete mix ratio at different ages through experiments; the tensile strength fitting module is used to obtain the fitting function of the surface tensile strength of concrete based on the concrete maturity theory according to the measured value of the internal temperature of the concrete and the surface tensile strength of concrete at different ages; the elastic modulus fitting module is used to obtain the predicted fitting function of the elastic modulus through the elastic modulus of concrete at different ages; the temperature control index acquisition module is used to obtain the relationship between the surface tensile strength of concrete at different ages and the surface tensile stress of the concrete surface according to the safety factor, and according to the relationship and in combination with the fitting function of the surface tensile strength of the concrete and the predicted fitting function of the elastic modulus, obtain the internal and surface control temperature difference of the concrete at different ages; the intelligent control module uses the internal and surface control temperature difference of the concrete at different ages to perform intelligent control on the curing environment temperature of the concrete.

[0120] Among them, the test data acquisition module of the present invention includes:

[0121] A concrete surface tensile strength acquisition module, which acquires the concrete surface tensile strength at different ages under the same concrete mix ratio by setting a number of concrete surface tensile strength tests under different concrete mix ratios;

[0122] A concrete elastic modulus acquisition module, which acquires the concrete elastic modulus at different ages by setting an elastic modulus test of the concrete.

[0123] The tensile strength fitting module of the present invention obtains the elastic modulus of concrete at different ages according to the test data acquisition, performs function fitting using the following formula to fit the elastic modulus growth rate coefficient c, and obtains the elastic modulus prediction fitting function, and performs fitting according to the following formula:

[0124] E(t) = E 0 +E 1 (1 - e -ct );

[0125] Among them, E(t) is the concrete elastic modulus (MPa) at age t, E 0 is the elastic modulus of the concrete at the end of final setting (MPa), E 1 is the elastic modulus at 28d under standard curing, and c is the elastic modulus growth rate coefficient.

[0126] Example 2:

[0127] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0128] Example 3:

[0129] A computer program product includes a computer program, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0130] The content not detailedly described in this specification belongs to the prior art well-known to those skilled in the art. Those skilled in the art should understand that the embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0131] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, and combinations of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processors of general-purpose computers, special-purpose computers, embedded processors, or other programmable data processing devices to generate a machine, such that the instructions executed by the processors of the computer or other programmable data processing devices produce means for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or one or more of the blocks.

[0132] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory produce a manufactured article including instruction means that implement the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or one or more of the blocks.

[0133] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or one or more of the blocks.

[0134] 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 the scope of its protection. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: after reading the present invention, those skilled in the art can still make various changes, modifications, or equivalent substitutions to the specific implementation manners of the invention, but these changes, modifications, or equivalent substitutions are all within the scope of the claimed protection of the invention pending approval.

[0135] The content not described in detail in this specification belongs to the known prior art of those skilled in the art.

Claims

1. An intelligent maintenance method driven by sensing the temperature and humidity field inside concrete, characterized in that: Follow these steps: The surface tensile strength of concrete and the elastic modulus of concrete at different ages under the same concrete mix ratio are obtained through experiments; Based on the concrete maturity theory and the tensile strength of concrete surface at different ages, the fitting function of the tensile strength of concrete surface is obtained. The elastic modulus at different ages was used to predict the fitting function of the elastic modulus; According to the safety factor, the relationship between the surface tensile strength of concrete at different ages and the tensile stress of the concrete surface is established, and according to the relationship and in combination with the fitting function of the surface tensile strength of concrete and the fitting function of elastic modulus prediction, the internal and surface controlled temperature difference of concrete at different ages is obtained; The temperature and humidity of the concrete curing environment are intelligently controlled by controlling the temperature difference between the inner and outer surfaces of concrete at different ages.

2. The intelligent maintenance method driven by sensing the temperature and humidity field inside concrete according to claim 1 is characterized in that: The test setup for obtaining the surface tensile strength of concrete and the elastic modulus of concrete at different ages with the same concrete mix ratio includes: By setting up several groups of concrete surface tensile strength tests under different concrete mix ratios, the surface tensile strength of concrete at different ages under the same concrete mix ratio is obtained respectively; By setting up a concrete elastic modulus test, the elastic modulus of concrete at different ages can be obtained.

3. The intelligent maintenance method driven by sensing the temperature and humidity field inside concrete according to claim 1 is characterized in that: The fitting function method of the concrete surface tensile strength is: According to the test data acquisition module, the measured values ​​of the surface tensile strength of concrete and the internal temperature of concrete at different ages with the same concrete mix ratio are obtained. The concrete tensile strength curve is fitted using the concrete maturity theory formula to obtain the regression coefficients a, b and the fitting function of the surface tensile strength of concrete at different ages. The fitting is performed according to the following formula: M = ∑(T+15) × Δt; Among them, f s (t) is the tensile strength of concrete surface at age t, M represents the maturity of concrete curing, T is the average value of the measured internal temperature of concrete per unit time, and Δt represents the time interval.

4. The intelligent maintenance method driven by sensing the temperature and humidity field inside concrete according to claim 1 is characterized in that: The method for obtaining the elastic modulus prediction fitting function is: According to the elastic modulus of concrete at different ages, the following formula is used for function fitting, the elastic modulus growth rate coefficient c is fitted, and the elastic modulus prediction fitting function is obtained, and fitting is performed according to the following formula: E(t)=E0+E1(1-e -ct ): Among them, E(t) is the elastic modulus of concrete at age t, E0 is the elastic modulus of concrete at final setting, E1 is the elastic modulus of concrete at 28 days under standard curing, and c is the elastic modulus growth rate coefficient.

5. The intelligent maintenance method driven by sensing the temperature and humidity field inside concrete according to claim 1 is characterized in that: The method for establishing the relationship between the surface tensile strength of concrete at different ages and the tensile stress of the concrete surface layer is: Assuming the safety factor β, the tensile strength of the concrete surface at age t is f s The relationship between (t) and the tensile stress of the concrete surface at age t is: f s (t)≥β·σ s (t); Among them, σ s (t) is the tensile stress of the concrete surface at age t (MPa); Get σ s The formula for (t) is: Where α is the linear expansion coefficient of concrete, E(t) is the elastic modulus of concrete at age t, ΔT ab (t) is the controlled temperature difference between the inner and outer surfaces of concrete at age t, K P Expressed as the stress relaxation coefficient caused by concrete creep.

6. The intelligent maintenance method driven by sensing the temperature and humidity field inside concrete according to claim 5 is characterized in that: The method for obtaining the internal and surface controlled temperature difference of concrete of different ages is: Set the concrete linear expansion coefficient α and the stress relaxation coefficient K caused by concrete creep P ; The fitting function f of the tensile strength of concrete surface at different ages s (t) and elastic modulus prediction fitting function E(t) to obtain the internal and external controlled temperature difference ΔT of concrete at different ages ab (t).

7. The intelligent maintenance method driven by sensing the temperature and humidity field inside concrete according to claim 1 is characterized in that: The temperature and humidity of the concrete curing environment are intelligently controlled by controlling the temperature difference between the inner and outer surfaces of concrete at different ages: according to the temperature difference ΔT between the inner and outer surfaces of concrete at different ages ab (t) and concrete curing humidity requirements, generate temperature and humidity curing instructions and transmit them to the intelligent curing device, the wireless receiving control device of the intelligent curing device receives the temperature and humidity curing instructions, and the intelligent curing device regulates the heating device and the humidifying device to execute the instructions.

8. An intelligent maintenance system driven by sensing the temperature and humidity field inside concrete, characterized in that: The system is operated according to the intelligent maintenance method driven by sensing of temperature and humidity field inside concrete as claimed in any one of claims 1 to 7, including: A test data acquisition module, which is used to obtain the surface tensile strength of concrete and the elastic modulus of concrete at different ages with the same concrete mix ratio through experiments; A tensile strength fitting module, wherein the tensile strength fitting module is used to obtain a fitting function of the tensile strength of the concrete surface based on the concrete maturity theory, according to the actual measured value of the concrete internal temperature and the tensile strength of the concrete surface at different ages; An elastic modulus fitting module, wherein the elastic modulus fitting module is used to obtain an elastic modulus prediction fitting function through elastic moduli of concrete at different ages; A temperature control index acquisition module, which is used to establish the relationship between the surface tensile strength of concrete at different ages and the tensile stress of the concrete surface layer according to the safety factor, and obtain the internal and external control temperature difference of concrete at different ages according to the relationship and in combination with the fitting function of the concrete surface tensile strength and the elastic modulus prediction fitting function; An intelligent control module is provided, wherein the intelligent control module uses the internal and external temperature differences of concrete at different ages to intelligently control the temperature of the concrete curing environment.

9. The intelligent maintenance system driven by sensing the temperature and humidity field inside concrete according to claim 8, characterized in that: The test data acquisition module comprises: A concrete surface tensile strength acquisition module, wherein the concrete surface tensile strength acquisition module obtains the concrete surface tensile strength of different ages under the same concrete mix ratio by setting a plurality of groups of concrete surface tensile strength tests under different concrete mix ratios; The concrete elastic modulus acquisition module acquires the elastic modulus of concrete at different ages by setting an elastic modulus test of concrete.

10. The intelligent maintenance system driven by sensing the temperature and humidity field inside concrete according to claim 8, characterized in that: The tensile strength fitting module obtains the elastic modulus of concrete of different ages according to the test data, performs function fitting using the following formula, fits the elastic modulus growth rate coefficient c, obtains the elastic modulus prediction fitting function, and performs fitting according to the following formula: E(t)=E0+E1(1-e -ct ): Among them, E(t) is the elastic modulus of concrete at age t, E0 is the elastic modulus of concrete at final setting, E1 is the elastic modulus of concrete at 28 days under standard curing, and c is the elastic modulus growth rate coefficient.

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