Coal gangue aggregate concrete creep deformation prediction method and system

Abstract

The invention provides a coal gangue aggregate concrete creep deformation prediction method and system, and belongs to the field of coal gangue aggregate concrete creep deformation prediction. The method aims at solving the problem that a coal gangue aggregate concrete creep performance prediction method does not exist at present. According to the method, a Counto model based on a two-phase composite material theory is utilized to construct an expression of influence of the coal gangue aggregate on a concrete creep final value and a creep development trend, the corresponding expression is introduced into an European standard EC2 creep model, and finally a coal gangue aggregate concrete creep prediction model is established. According to the method, the concrete creep final value amplification coefficient expression is introduced, the amplification coefficient is introduced into the European standard EC2 model, the creep deformation model expression and the amplification coefficient are not mentioned in an existing method, and the blank in the aspect of coal gangue aggregate concrete creep performance prediction is filled up; the effectiveness of the coal gangue aggregate concrete creep deformation prediction model designed by the invention is proved through tests.

Description

Technical Field

[0001] This invention relates to the field of creep deformation prediction technology for coal gangue aggregate concrete, and more specifically, to a method and system for predicting creep deformation of coal gangue aggregate concrete. Background Technology

[0002] The low strength, large deformation, and poor long-term performance of coal gangue aggregate concrete limit its widespread application in building structural engineering. Accurately predicting the mechanical properties of coal gangue aggregate concrete is a crucial step in promoting its structural application. However, most existing predictive models for the mechanical properties of coal gangue aggregate concrete are based on limited experimental data obtained through regression analysis, resulting in limited accuracy. Furthermore, most models only consider the case where coarse coal gangue aggregate replaces natural coarse aggregate, failing to characterize the impact of fine coal gangue aggregate on the concrete. The long-term performance of concrete affects the service life of concrete structures. Therefore, the large long-term deformation (shrinkage and creep) of coal gangue aggregate concrete deserves significant attention, but currently, there is a lack of research on its creep performance. Accurately predicting the performance of coal gangue aggregate concrete can guide its use, promote its application in building structural engineering, and enhance the resource utilization value of coal gangue, aligning with the national trend of developing a green and circular economy. Summary of the Invention

[0003] The technical problem to be solved by this invention is:

[0004] To address the current lack of a method for predicting the creep performance of coal gangue aggregate concrete.

[0005] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0006] This invention provides a method for predicting creep deformation of coal gangue aggregate concrete, comprising the following steps:

[0007] S100. Based on the creep final value formula of ordinary concrete, a creep final value formula of coal gangue aggregate concrete is constructed.

[0008] S200. Based on the final value formula for creep of coal gangue aggregate concrete in step S100, assuming that the creep deformation of coal gangue aggregate concrete is caused by the creep of cement paste, and assuming that the creep of cement paste in coal gangue aggregate concrete is the same as the creep in ordinary concrete, construct the amplification factor formula for the final value of creep deformation.

[0009] S300, based on the EC2 model, constructs a creep development trend prediction model.

[0010] Further, in step S100, for ordinary concrete, its final creep deformation is calculated using the following formula:

[0011]

[0012] In the formula, c NAC Represents the creep deformation of ordinary concrete; α represents the total volume fraction of natural coarse aggregate and natural fine aggregate in ordinary concrete. NAC c represents a coefficient related to aggregate stiffness. p Represents the creep deformation of cement paste;

[0013] For coal gangue aggregate concrete, its final creep value is calculated using the following formula:

[0014]

[0015] In the formula, c CGAC Represents the creep deformation value of coal gangue aggregate concrete; α represents the volume fraction of total aggregate in coal gangue aggregate concrete; CGAC This represents a coefficient related to aggregate stiffness.

[0016] Furthermore, α NAC The value is 1.33.

[0017] Furthermore, in step S200, the amplification factor k a As given by equation (3):

[0018]

[0019] In the formula, , These represent the volume fractions of natural coarse aggregate and natural fine aggregate in ordinary concrete, respectively. , These represent the volume fractions of coarse and fine coal gangue aggregates in coal gangue aggregate concrete, respectively. , These represent the volume fractions of natural coarse aggregate and natural fine aggregate in coal gangue aggregate concrete, respectively.

[0020] Furthermore, when volume substitution is used, the volume fractions of coarse and fine aggregates in coal gangue aggregate concrete are equal to those in ordinary concrete, as shown in equations (4) and (5):

[0021]

[0022] Substituting equations (4) and (5) into equation (3), we get:

[0023]

[0024] Among them, the coefficient α related to the stiffness of coal gangue aggregate is... CGAC Calculate using the following formula:

[0025]

[0026] Where, μ CGAC The Poisson's ratio representing coal gangue aggregate concrete is taken as 0.2; μ CGA The Poisson's ratio representing the aggregate in coal gangue aggregate concrete is taken as 0.25; E CGAC The elastic modulus of coal gangue aggregate concrete; This represents the elastic modulus of the aggregate in coal gangue aggregate concrete.

[0027] After simplification, we obtain equation (8):

[0028]

[0029] From equation (8), we can see that the coefficient α CGAC The elastic modulus of coal gangue aggregate concrete is related to the elastic modulus of the aggregates within it. Since the elastic modulus of coal gangue aggregate concrete can be directly measured experimentally, it is only necessary to determine the elastic modulus of the aggregates in the coal gangue aggregate concrete; thus, the amplification factor k for the final value of creep deformation can be obtained. a :

[0030]

[0031] In the formula, This refers to the volume fraction of coarse aggregate from coal gangue in the total aggregate. r represents the volume fraction of fine aggregate from coal gangue in the total aggregate; CGCA r represents the replacement rate of coal gangue coarse aggregate. CGFA This represents the replacement rate of fine aggregates from coal gangue.

[0032] Furthermore, in step S300, the creep development trend prediction model based on the EC2 model is obtained. As in equation (10):

[0033]

[0034] In the formula, t represents the concrete age; t0 represents the loading age; β H This represents a coefficient related to the specimen size and the relative humidity of the environment. A system for predicting creep deformation of coal gangue aggregate concrete is provided. This system has program modules corresponding to the steps described above, and executes the steps in the method for predicting creep deformation of coal gangue aggregate concrete described above during operation.

[0035] A computer-readable storage medium storing a computer program configured to, when invoked by a processor, implement the steps of a method for predicting creep deformation of coal gangue aggregate concrete.

[0036] Compared with the prior art, the beneficial effects of the present invention are:

[0037] This invention studies the effects of single and multiple admixtures of coarse and fine coal gangue aggregates on the creep deformation of concrete with different water-cement ratios, revealing the influence mechanism. Using the Counto model based on two-phase composite material theory, an expression is constructed to show the influence of coal gangue aggregates on the final creep value and creep development trend of concrete. The corresponding expression is then introduced into the European standard EC2 creep model, and finally a creep prediction model for concrete with coal gangue aggregates is established.

[0038] In constructing the creep deformation prediction model for coal gangue aggregate concrete, this invention considers the stiffness of the coal gangue aggregate, which has a significant impact on the final creep value of the concrete. Therefore, a creep final value amplification factor k is introduced. a The creep prediction model for coal gangue aggregate concrete is obtained by using an expression to characterize the creep deformation and incorporating the amplification factor into the European standard EC2 model. The above-mentioned creep deformation model expression and amplification factor are not mentioned in existing methods, filling a gap in the prediction of creep performance of coal gangue aggregate concrete. Furthermore, experimental testing shows that the model of this invention agrees well with the experimental results, with a maximum deviation of only 7.6% in the final creep value, proving the effectiveness of the creep deformation prediction model for coal gangue aggregate concrete designed in this invention. Attached Figure Description

[0039] Figure 1 The diagram shows the creep test device for coal gangue aggregate concrete in an embodiment of the present invention, wherein (a) is a structural diagram of the self-balancing loading device and (b) is a diagram of the terminal layout.

[0040] Figure 2 This is a comparison of the creep deformation curves of coal gangue aggregate concrete and ordinary concrete over time in an embodiment of the present invention.

[0041] Figure 3 This is a comparison chart of the final creep values ​​of coal gangue aggregate concrete and ordinary concrete in an embodiment of the present invention.

[0042] Figure 4 This is a comparison chart of the creep development trends of coal gangue aggregate concrete and ordinary concrete in embodiments of the present invention;

[0043] Figure 5 The (c) measured in the embodiments of the present invention CGAC / c NAC ) ex and the (c) calculated by the prediction modelCGAC / c NAC ) pre Comparison chart;

[0044] Figure 6 This is a comparison chart of the creep development trend and the predicted creep development trend of the coal gangue aggregate concrete specimen test in the embodiment of the present invention. Detailed Implementation

[0045] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0046] Test methods

[0047] The experimental parameter design is presented. Specifically, to study the effect of the replacement rates of coarse and fine coal gangue aggregates on the creep performance of coal gangue aggregate concrete, four combinations of replacement rates were designed: 0% replacement rate for both coarse and fine coal gangue aggregates; 100% replacement rate for both coarse and fine coal gangue aggregates; 100% replacement rate for coarse coal gangue aggregates and 0% replacement rate for fine coal gangue aggregates; and 0% replacement rate for coarse coal gangue aggregates and 100% replacement rate for fine coal gangue aggregates. Simultaneously, to analyze the effect of different water-cement ratios on coal gangue aggregates, two different water-cement ratios (0.55 and 0.35) were designed. In this context, t0 represents the age of the specimen at the time of loading; N L This represents the long-term load value borne by the specimen; n c The initial stress ratio represents the initial stress ratio of the specimen (i.e., the longitudinal stress of the concrete at the start of load bearing divided by the average compressive strength of the cylinder. This average compressive strength of the cylinder is calculated according to the "Standard for Design of Concrete Structures" GB / T 50010-2010 and the European standard CEB-FIP Model Code 2010).

[0048] surface Creep test parameters of coal gangue aggregate concrete

[0049]

[0050] The specimen number contains four elements: 1) NAC represents ordinary concrete, and CGAC represents coal gangue aggregate concrete; 2) coarse aggregate is represented by C and fine aggregate by F; 3) the suffixes C and F indicate the replacement rate of coal gangue aggregate; 4) the last number indicates the water-cement ratio. Taking the typical specimen CGAC-C50-F50-0.35 as an example, the replacement rate of both coarse and fine coal gangue aggregate in this coal gangue aggregate concrete specimen is 50%, and the water-cement ratio is 0.35. CGCA r represents the replacement rate of coal gangue coarse aggregate. CGFA This represents the replacement rate of fine aggregates from coal gangue.

[0051] Specimen curing and measurement

[0052] The mixed concrete was poured into a 100mm×100mm×400mm concrete mold. To prevent moisture loss, a plastic film was placed over the concrete surface. The specimens were demolded after one day of curing and then immersed in a water tank for further curing to minimize the impact of autogenous shrinkage on the test. Once the specimens reached the test age, they were removed from the water tank and placed in the laboratory for further processing in preparation for creep loading and measurement.

[0053] A self-balancing loading device is adopted. (a) In this section, concrete creep was tested according to GB / T 50082-2009, "Standard for Test Methods of Long-Term Performance and Durability of Ordinary Concrete". The creep value was obtained by subtracting the shrinkage deformation value of the shrinkage specimen from the total deformation value of the creep specimen.

[0054] Before loading the test, to ensure that the long-term load on creep specimens in the same group was the same, two creep specimens in the same group were stacked vertically and their geometric alignment was checked. To ensure that creep and shrinkage specimens in the same group were in the same environment, the specimens in the same group were placed adjacent to each other. The method of applying the long-term load was to tighten the reaction plate with a hydraulic jack, and when the load reached the predetermined value, the tension of each screw was adjusted to keep the concrete specimen under axial compression. A 20t force sensor between the loading plates was used to monitor the applied load in real time. A portable handheld displacement gauge was used to monitor the deformation of the four sides of the specimen over a long period of time. (b) in the middle.

[0055] Axial compression loading was applied to concrete specimens in four stages, with each stage defined as 25% of the target holding load. To ensure the specimens remained under axial compression throughout, strain was measured on all four surfaces of the specimen using a portable handheld displacement gauge after each load stage. The screw tension was adjusted based on the measured data to maintain axial compression. Considering load relaxation due to creep during long-term loading, additional loading was applied to ensure the holding load remained within ±2% of the initial load. The experiment lasted 326 days, and the ambient humidity in the laboratory was maintained at 50±10% throughout the entire experiment.

[0056] Experimental Results and Analysis

[0057] The curves showing the creep strain development over time of concrete specimens with different replacement rates of coarse and fine coal gangue aggregates are presented. The creep development curve of coal gangue aggregate concrete predicted by the model of this invention is also shown. The creep strain of the two specimens in each group is given. This value is obtained by subtracting the shrinkage strain of the shrinkage specimen from the total strain of the creep specimen. Here, a and b represent experimental group a and experimental group b, the proposed model is the model of this invention, and EC2 represents the creep calculated using the European standard.

[0058] The creep strain of all specimens increased continuously over time, with a larger rate of increase in the first 60 days of the test, followed by a gradual slowdown. For all specimens, the creep deformation before 150 days reached more than 80% of the creep deformation at the end of the test. This indicates that although creep deformation increases throughout the service life of concrete, the results of the 326-day creep test in this invention provide relatively sufficient information.

[0059] Since the final value of creep deformation and the creep development trend are both key factors determining the creep deformation of concrete, the influence of coal gangue aggregate on the final value of creep deformation and the creep development trend are analyzed below.

[0060] The Influence of Coal Gangue Aggregate on the Final Value of Creep

[0061] To investigate the influence of coarse and fine aggregates of coal gangue on the final creep value of concrete, The final creep values ​​of coal gangue aggregate concrete with different mix proportions and different coal gangue aggregate replacement rates were compared. Among them, r c r represents the coarse aggregate replacement rate. f The value represents the fine aggregate replacement rate. The results show that, at different water-cement ratios (w / c), the final creep value of coal gangue aggregate concrete is significantly higher than that of ordinary concrete, ranging from 35.8% to 134.9%. This difference is attributed to the fact that concrete creep is primarily caused by the creep of the cement paste, while the aggregate constrains its deformation; both factors work together. Compared to natural aggregates, porous coal gangue aggregate has lower stiffness and a weaker constraint on the creep deformation of the cement paste. This reduced constraint results in coal gangue aggregate concrete exhibiting greater creep deformation.

[0062] from It can also be seen that the increase in the final creep value caused by coarse coal gangue aggregate is more significant than that caused by fine coal gangue aggregate. The final creep value of concrete containing coarse coal gangue aggregate is 72.3% to 87.3% higher than that of ordinary concrete, while the final creep value of concrete specimens containing fine coal gangue aggregate is only 35.8% to 38.0% higher than that of ordinary concrete. This is because the proportion of coarse aggregate in concrete is higher, resulting in a more significant weakening effect of coal gangue aggregate on the restraining effect of cement paste creep deformation. Specifically, the volume fraction of coarse coal gangue aggregate in specimens CGAC-C100-F0-0.55 and CGAC-C100-F0-0.35 was 0.40–0.43, while the volume fraction of fine coal gangue aggregate in specimens CGAC-C0-F100-0.55 and CGAC-C0-F100-0.35 was only 0.24–0.27.

[0063] By comparison As shown in (a) and (b), the influence of coarse and fine coal gangue aggregates on the final creep value of concrete weakens as the water-cement ratio decreases. When the water-cement ratio is 0.55, the final creep value of coal gangue aggregate concrete is 38.0% to 134.9% higher than that of natural aggregate concrete (ordinary concrete), while this percentage range shrinks to 35.8% to 127.2% when the water-cement ratio drops to 0.35. This is mainly because the cement paste is denser at lower water-cement ratios. Specifically, the restraining effect of aggregates on the creep deformation of cement paste depends on the stiffness difference between aggregates and cement paste. Increasing the stiffness of cement paste reduces the stiffness difference between the two, thereby weakening the restraining effect of aggregates, ultimately making the final creep value of coal gangue aggregate concrete specimens with low water-cement ratios less affected by aggregates.

[0064] The Influence of Coal Gangue Aggregate on Creep Development Trend

[0065] The effects of coarse and fine coal gangue aggregates on the creep development trend of concrete were analyzed. Normalized creep deformation was used, calculated by dividing the creep deformation ε(t) by the final creep deformation value ε(t) measured at the end of the experiment. end (i.e., using ε(t) and ε(t)) end The ratio of creep to creep development trend is used to characterize the creep development trend.

[0066] Depend on As can be seen, regardless of whether coal gangue coarse aggregate, coal gangue fine aggregate, or both are added separately, the creep development law of coal gangue aggregate concrete is basically consistent with that of ordinary concrete. This is because the creep development law of concrete of the same size is directly related to the water diffusion rate, which depends on the pore structure of the concrete, especially the water release channels. Since this invention uses an 80% additional water method to prepare coal gangue aggregate concrete, ensuring that its effective water-cement ratio is consistent with that of ordinary concrete, the two have similar pore structures. Therefore, although the addition of coal gangue aggregate increases the total water consumption, the similar water release channels of coal gangue aggregate concrete and ordinary concrete result in comparable water diffusion rates, i.e., similar creep development trends.

[0067] Since the incorporation of coal gangue aggregate has a significant impact on the final creep value of coal gangue aggregate concrete, and this impact is mainly related to the stiffness of the coal gangue aggregate, the increase in the final creep value caused by coal gangue aggregate can be mitigated by introducing an amplification factor k related to the stiffness of the coal gangue aggregate into the EC2 model. a To characterize.

[0068] Specific Implementation Scheme 1: This invention provides a method for predicting creep deformation of coal gangue aggregate concrete, including the following steps:

[0069] S100. When cement paste in concrete undergoes creep, the aggregate has a restraining effect on this deformation, and the combined effect of both leads to the creep of the concrete. For ordinary concrete, its final creep value can be calculated by the following formula:

[0070]

[0071] In the formula, c NAC Represents the creep deformation of ordinary concrete; α represents the total volume fraction of natural coarse aggregate and natural fine aggregate in ordinary concrete. NAC This represents a coefficient related to aggregate stiffness; for natural aggregates, it can be taken as 1.33 according to the research of Fathifazl et al.; c p Represents the creep deformation of cement paste;

[0072] Similarly, for coal gangue aggregate concrete, its creep deformation can be calculated using the following formula:

[0073]

[0074] In the formula, c CGAC Represents the creep deformation of coal gangue aggregate concrete; α represents the volume fraction of total aggregate in coal gangue aggregate concrete; CGAC A coefficient representing the stiffness of aggregate;

[0075] S200. Construct a prediction formula to predict the impact of coal gangue coarse aggregate and coal gangue fine aggregate on the final value of concrete creep.

[0076] Assuming that the creep deformation of coal gangue aggregate concrete is caused by the creep of cement paste, and that the creep of cement paste is constrained by the coarse and fine coal gangue aggregates, as well as the natural coarse and fine aggregates in the coal gangue aggregate concrete; and assuming that the effective water-cement ratio of coal gangue aggregate concrete is similar to that of ordinary concrete, it is assumed that the creep of cement paste in coal gangue aggregate concrete is the same as that in ordinary concrete; based on these assumptions, the amplification factor k is... a As given by equation (3):

[0077]

[0078] In the formula, , These represent the volume of natural coarse aggregate and natural fine aggregate in ordinary concrete divided by the volume of concrete; that is, the volume fraction of natural coarse aggregate and natural fine aggregate in ordinary concrete. , These represent the volume of coarse coal gangue aggregate and fine coal gangue aggregate in coal gangue aggregate concrete divided by the volume of concrete; that is, the volume fraction of coarse coal gangue aggregate and fine coal gangue aggregate in coal gangue aggregate concrete. , These represent the volume of natural coarse aggregate and natural fine aggregate in coal gangue aggregate concrete divided by the volume of concrete; that is, the volume fraction of natural coarse aggregate and natural fine aggregate in coal gangue aggregate concrete.

[0079] When volume substitution is used, the volume fractions of coarse and fine aggregates in coal gangue aggregate concrete are equal to those in ordinary concrete, as shown in equations (4) and (5):

[0080]

[0081] Substituting equations (4) and (5) into equation (3) and simplifying, we get:

[0082]

[0083] Among them, the coefficient α related to the stiffness of coal gangue aggregate is... CGAC The following formula can be used for calculation:

[0084]

[0085] In the formula, μ CGAC The Poisson's ratio for coal gangue aggregate concrete can be taken as 0.2, the same as for ordinary concrete; μ CGAThe Poisson's ratio representing the aggregate in coal gangue aggregate concrete can be taken as 0.25, the same as that of natural aggregate; E CGAC The elastic modulus of coal gangue aggregate concrete; This represents the elastic modulus of the aggregate in coal gangue aggregate concrete.

[0086] After simplification, we get equation (8):

[0087]

[0088] From equation (8), we can see that the coefficient α CGAC The elastic modulus of coal gangue aggregate concrete is related to the elastic modulus of the aggregates within it. Since the elastic modulus of coal gangue aggregate concrete can be directly measured experimentally, it is only necessary to determine the elastic modulus of the aggregates in the coal gangue aggregate concrete; thus, the amplification factor k for the final value of creep deformation can be obtained. a :

[0089]

[0090] in, This refers to the volume fraction of coarse aggregate from coal gangue in the total aggregate. r represents the volume fraction of fine aggregate from coal gangue in the total aggregate; CGCA r represents the replacement rate of coal gangue coarse aggregate. CGFA This represents the replacement rate of fine aggregates from coal gangue;

[0091] To verify the accuracy of the model, this invention compared the c of the concrete specimens measured at the end of the experiment. CGAC / c NAC The prediction results of the corresponding model, such as It can be observed that the model proposed in this invention can accurately predict the final creep value of coal gangue aggregate concrete, with a maximum deviation within 10%, an average ratio of predicted value to experimental value of 0.985, and a coefficient of variation of 0.051.

[0092] S300. Since the creep development trend of coal gangue aggregate concrete is similar to that of ordinary concrete, the creep development trend prediction model in the EC2 model is adopted in the prediction of the creep development trend of coal gangue aggregate concrete. As in equation (10):

[0093]

[0094] In the formula, t represents the concrete age in days; t0 represents the loading age in days; β H A coefficient representing the relationship between specimen size and relative humidity of the environment;

[0095] The measured ε(t) / ε(t) in the experiment were compared. end The values ​​are compared with those predicted using formula (10). It can be observed that the EC2 model can predict the creep development trend of coal gangue aggregate concrete specimens well, with an average value of 0.990 and a coefficient of variation of 0.107. Therefore, formula (10) can be used to predict the creep development trend of coal gangue aggregate concrete.

[0096] Specific implementation scheme two: The present invention provides a creep deformation prediction system for coal gangue aggregate concrete. The system has a program module corresponding to the above steps, and executes the steps in the above-mentioned method for predicting creep deformation of coal gangue aggregate concrete when running.

[0097] The other combinations and connections in this implementation scheme are the same as in Specific Implementation Scheme 1.

[0098] Specific Implementation Scheme 3: The present invention provides a computer-readable storage medium storing a computer program configured to implement, when called by a processor, the steps of a method for predicting creep deformation of coal gangue aggregate concrete.

[0099] The other combinations and connections in this implementation scheme are the same as in Specific Implementation Scheme 1.

[0100] This invention compares the model prediction results with the measured creep deformation of coal gangue aggregate concrete. For example... As shown, the predicted results agree well with the experimental results. For coal gangue aggregate concrete with a water-cement ratio of 0.55, the error range of the final creep value is 2.6% to 7.6%; for coal gangue aggregate concrete with a water-cement ratio of 0.35, the error is between 5.5% and 5.9%. These results demonstrate that the creep prediction model proposed in this invention can effectively predict the creep deformation of coal gangue aggregate concrete.

[0101] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A method for predicting creep deformation of coal gangue aggregate concrete, characterized in that, Includes the following steps: S100. Based on the creep final value formula of ordinary concrete, a creep final value formula of coal gangue aggregate concrete is constructed. S200. Based on the final value formula for creep of coal gangue aggregate concrete in step S100, assuming that the creep deformation of coal gangue aggregate concrete is caused by the creep of cement paste, and assuming that the creep of cement paste in coal gangue aggregate concrete is the same as the creep in ordinary concrete, construct the amplification factor formula for the final value of creep deformation. S300, based on the EC2 model, constructs a creep development trend prediction model.

2. The method for predicting creep deformation of coal gangue aggregate concrete according to claim 1, characterized in that: In step S100, for ordinary concrete, its final creep deformation is calculated using the following formula: ； In the formula, c NAC Represents the creep deformation of ordinary concrete; α represents the total volume fraction of natural coarse aggregate and natural fine aggregate in ordinary concrete. NAC c represents a coefficient related to aggregate stiffness. p Represents the creep deformation of cement paste; For coal gangue aggregate concrete, its final creep value is calculated using the following formula: ； In the formula, c CGAC Represents the creep deformation value of coal gangue aggregate concrete; α represents the volume fraction of total aggregate in coal gangue aggregate concrete; CGAC This represents a coefficient related to aggregate stiffness.

3. The method for predicting creep deformation of coal gangue aggregate concrete according to claim 2, characterized in that: α NAC The value is 1.

33.

4. The method for predicting creep deformation of coal gangue aggregate concrete according to claim 3, characterized in that: In step S200, the amplification factor k a As given by equation (3): ； In the formula, , These represent the volume fractions of natural coarse aggregate and natural fine aggregate in ordinary concrete, respectively. , These represent the volume fractions of coarse and fine coal gangue aggregates in coal gangue aggregate concrete, respectively. , These represent the volume fractions of natural coarse aggregate and natural fine aggregate in coal gangue aggregate concrete, respectively.

5. The method for predicting creep deformation of coal gangue aggregate concrete according to claim 4, characterized in that: When volume substitution is used, the volume fractions of coarse and fine aggregates in coal gangue aggregate concrete are equal to those in ordinary concrete, as shown in equations (4) and (5): ； Substituting equations (4) and (5) into equation (3), we get: ； Among them, the coefficient α related to the stiffness of coal gangue aggregate is... CGAC Calculate using the following formula: ； In the formula, μ CGAC The Poisson's ratio representing coal gangue aggregate concrete is taken as 0.2; μ CGA The Poisson's ratio representing the aggregate in coal gangue aggregate concrete is taken as 0.25; E CGAC The elastic modulus of coal gangue aggregate concrete; This represents the elastic modulus of the aggregate in coal gangue aggregate concrete. After simplification, we obtain equation (8): ； From equation (8), we can see that the coefficient α CGAC The elastic modulus of coal gangue aggregate concrete is related to the elastic modulus of the aggregates within it. Since the elastic modulus of coal gangue aggregate concrete can be directly measured experimentally, it is only necessary to determine the elastic modulus of the aggregates in the coal gangue aggregate concrete; thus, the amplification factor k for the final value of creep deformation can be obtained. a : ； in, This refers to the volume fraction of coarse aggregate from coal gangue in the total aggregate. r represents the volume fraction of fine aggregate from coal gangue in the total aggregate; CGCA r represents the replacement rate of coal gangue coarse aggregate. CGFA This represents the replacement rate of fine aggregates from coal gangue.

6. The method for predicting creep deformation of coal gangue aggregate concrete according to claim 5, characterized in that: In step S300, the creep development trend prediction model based on the EC2 model is obtained. As in equation (10): ； In the formula, t represents the concrete age; t0 represents the loading age; β H This represents a coefficient related to the specimen size and the relative humidity of the environment.

7. A system for predicting creep deformation of coal gangue aggregate concrete, characterized in that: The system has a program module corresponding to the steps described in any one of claims 1-6 above, and executes the steps in the above-described method for predicting creep deformation of coal gangue aggregate concrete when it is run.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program configured to, when invoked by a processor, implement the steps of the method for predicting creep deformation of coal gangue aggregate concrete according to any one of claims 1-6.

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