Concrete rheological property testing method, application and feedback control system

Abstract

The invention relates to the technical field of constructional engineering, and mainly discloses a concrete rheological property testing method, application and a feedback control system.The method comprises the steps that torque and rotating speed data of concrete are measured through a rheometer, and yield stress and plastic viscosity are iteratively calculated in combination with a Herbach model; the concrete fluidity is comprehensively represented by the shear work parameter SWI innovatively, self-adaptive adjustment of the vibration duration is achieved, the feedback control system comprises a rheometer, a sensor module, a control host and vibration equipment, remote wireless control is supported, the problem that traditional rheological parameter multi-index evaluation is inconsistent is solved, and the method is suitable for large-scale popularization and application. The vibrating process is optimized through a single SWI parameter, the concrete compactness and the construction efficiency are improved, the repeated test deviation is smaller than 5%, and the reliability and the engineering applicability of the method are verified.

Description

Technical Field

[0001] The invention relates to the technical field of construction engineering, and in particular to a concrete rheological property testing method, application and feedback control system. Background Art

[0002] Good concrete workability is the basic prerequisite for the smooth progress of concrete construction. It is also an important condition to ensure that hardened concrete has excellent homogeneity, mechanical properties and durability. It is crucial to ensure the quality of concrete structure engineering. Fluidity is an important component of concrete workability. How to prepare concrete with excellent fluidity has always been a concern of construction industry practitioners. Traditional testing methods can usually only describe fresh concrete from a single perspective, usually called the "single-point method". In order to fully understand the rheological behavior of concrete, multiple tests need to be carried out simultaneously from different perspectives.

[0003] The slump test is the main means of testing and characterizing the fluidity of concrete. However, the slump can only reflect one aspect of the fluidity of concrete, namely its yield stress. To fully express the fluidity of concrete, at least one more parameter characterizing the viscosity of concrete must be added. GH Tattersall first tested the rheological properties of cement paste and cement concrete, introduced plastic viscosity into the characterization of the rheological properties of concrete, and believed that cement paste and concrete conformed to the Bingham model. The rheometer method uses multiple parameters such as yield stress and plastic viscosity to characterize fresh concrete, overcoming the limitation of the "single point method" that can only reflect one aspect of the performance of concrete fluidity.

[0004] As the research progresses, concrete scholars have found that concrete is more consistent with nonlinear models such as the Heba (HB) model and the modified Bingham model in many cases. However, there are two disadvantages in using these nonlinear models to characterize concrete. One is that the complex form makes it difficult to promote and apply; the other is that the physical meaning is not as simple and clear as the Bingham model.

[0005] At present, rheological methods need to use multiple parameters to characterize the performance of concrete when studying concrete. When the influence rules expressed by various parameters in the same rheological model are inconsistent, there is a lack of a single indicator for quantitatively comparing the fluidity of different concrete mixtures. Summary of the invention

[0006] The purpose of the present invention is to solve the technical problems existing in the prior art, and to provide a concrete rheological property testing method, an application of a shear work parameter SWI in concrete vibration, and a concrete rheological property feedback adjustment system. The present invention integrates the yield stress and plastic viscosity measured by the rheological property measurement system into a new parameter, the shear work parameter SWI, which provides a parameter for concrete vibration that more comprehensively reflects the workability of concrete.

[0007] To achieve the above object, the present invention adopts the following technical scheme: a method for testing the rheological properties of concrete, comprising the following steps:

[0008] S1. Load the fresh concrete sample to be tested into the outer cylinder of the rheometer, the inner diameter of the outer cylinder of the rheometer is R0;

[0009] S2. The torque and speed sensors of the rheometer are used to measure the torque T and speed N of the mixing blade when the concrete is rotating in real time;

[0010] S3. When the stirring blade of the rheometer rotates, it forms a radius R with the concrete inside. i The height of the stirring blade is h;

[0011] S4. The rheometer host applies a plurality of different stirring blade rotation speeds N, and obtains the torque T at the rotation speed;

[0012] Calculate the rheological parameter SWI according to the following steps (a) to (l):

[0013] (a) Fit the relationship between variable T and variable N according to formula (1), and obtain parameter G by least square method or software calculation HB , H HB and J;

[0014] T=G HB +H HB N J (1)

[0015] (b) Calculate the initial Herbach fluid parameter yield stress τ according to formulas (2) to (4) 0,HB , flow index n and consistency coefficient K;

[0016]

[0017] n=J (3)

[0018]

[0019] (c) Determine the critical radius R at the boundary between the static area and the moving area according to formula (5): p ;

[0020] R p =(T / 2πhτ 0,HB ) 1 / 2 (5)

[0021] (d) Calculate the corrected speed N obtained from the rheological parameters according to formula (6) or (7): mod , where R p ≤R oWhen Rp>Ro, use formula (6); when Rp>Ro, use formula (7);

[0022]

[0023]

[0024] (e) According to formula (8), the seven groups of test speeds N described in step (1) and the correction speeds N described in step (d) are calculated. mod Calculate the root mean square error RMSE;

[0025]

[0026] (f) Change the rheological parameter τ 0,HB , K, n, repeat the above steps until the rheological parameter τ with the minimum RMSE is obtained 0,HB , K, n, can be achieved through the planning and solving function of Excel.

[0027] (g) Use formula (9) to determine the initial μ value.

[0028]

[0029] Where n and K are the values ​​determined in step (f), is the maximum shear rate.

[0030] (h) Use formula (10) or formula (11) to calculate the corrected speed Ω MOD , where R p ≤R o When using formula (10), R p >Ro, use formula (11);

[0031]

[0032] (i) calculating the rotation speed Ω calculated in step (a) according to formula (12);

[0033] Ω=2πN (12)

[0034] (j) for 7 groups of the rotation speed Ω described in step (j) and the modified rotation speed Ω described in step (i) MOD Calculate the root mean square error (RMSE).

[0035] Calculate the root mean square error (RMSE) according to formula (12);

[0036]

[0037] (k) Change the rheological parameter μ and repeat the above steps until the rheological parameter μ with the minimum RMSE is obtained, which can be achieved through the planning and solving function of Excel;

[0038] (l) Use step (f) to obtain τ 0,HB Let τ0 be τ0, and use μ obtained in step (k) to calculate the shear work parameter SWI according to formula (14).

[0039]

[0040] Where: s, ρ and a are three preset constants. s is the shear motion distance, which can be selected according to the amplitude of the vibrating rod; ρ is the concrete density, obtained by the test; a is the shear motion acceleration, which can be selected according to the vibration acceleration amplitude.

[0041] A concrete rheological property feedback control system comprises the rheometer in the above-mentioned test method, wherein the rheometer comprises an outer cylinder, a support plate and a bottom cover, wherein the outer cylinder is a cylinder that passes through from top to bottom, the support plate is provided with the top of the outer cylinder, the support plate is clamped with the upper edge of the outer cylinder, the bottom cover is provided at the bottom of the outer cylinder, the bottom cover can be opened and closed, and when opened, the concrete contained in the outer cylinder can be released, and a plurality of anti-slip strips running up and down are evenly arranged on the inner wall of the outer cylinder, and the anti-slip strips are used to prevent the concrete from contacting with the inner wall of the outer cylinder when the rheometer is working. In order to avoid the calculation error caused by relative sliding, the motor, reducer and coupling are arranged from top to bottom on the support plate, and the motor, reducer and coupling are connected in sequence. A stirring blade is arranged inside the outer cylinder, and the shaft of the stirring blade is coaxially arranged with the outer cylinder. The stirring blade has a cross-shaped cross section, and the stirring blade is detachably connected to the coupling. A hopper connected to the inner part of the outer cylinder is arranged on the upper edge of the outer cylinder, and the hopper extends obliquely outward. The feed hopper is trumpet-shaped, large outside and small inside, so as to facilitate the loading of concrete. The inner diameter of the outer cylinder is Ro. When the stirring blade rotates, it forms a radius of R together with the concrete inside it. i The height of the stirring blade is h.

[0042] The method further includes a sensor module, wherein the sensors include a torque sensor and a speed sensor; a control host module, wherein the torque sensor and the speed sensor are communicatively connected to the control host, and the torque T and the speed N of the stirring blade during rotation are measured in real time to the control host, and the control host calculates the rheological parameter SWI according to steps (a) to (l) in the above-mentioned test method; a feedback control module and a vibrating device, wherein the control host is communicatively connected to the feedback control module, and the feedback control module is electrically connected to the vibrating device, and the control host calculates the vibration time according to the rheological parameters, and controls the vibration time of the vibrating device through the feedback control module.

[0043] It also includes a remote control module, the control host is wirelessly connected to the remote control module, the remote control module remotely obtains rheological parameter data and vibration time data, and remotely controls the vibration time of the vibration equipment through the remote control module.

[0044] A method for applying the concrete rheological property test method in concrete vibration comprises the following steps:

[0045] Establish the corresponding relationship between SWI value and vibration time t:

[0046] t = k·SWI + b (15)

[0047] Early experiments were conducted with concrete of various mix proportions to test the actual vibration time of concrete of two mix proportions and calculate the SWI values ​​of concrete of different mix proportions;

[0048] Substitute multiple sets of data into formula (15) to calculate the values ​​of k and b, and determine the vibration time of the concrete to be tested through the SWI value.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] The rheological parameter SWI in the present invention reflects the amount of work per unit area required for the concrete fluid to move a certain distance under a certain acceleration under the action of shear force. The larger the value, the more difficult it is to make the concrete accelerate, that is, the worse the fluidity. In actual construction, shear is generated on the concrete during mixing, transportation and manual transfer, so this parameter can reflect the difficulty of a series of operations in concrete construction. The influence of plastic viscosity on SWI is related to the movement distance, acceleration and concrete density, and the influence of yield stress on SWI is related to the movement distance but not to acceleration. It can be seen that under different conditions, the influence of yield stress and plastic viscosity on the amount of work is different. When using SWI for analysis, technicians can set appropriate a and s values ​​according to the application scenario. Rheological parameters can be used as a beneficial supplement to existing experimental methods for concrete fluidity and rheological properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] 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 some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0052] Figure 1 It is a flow chart of the concrete rheological property testing method of the present invention;

[0053] Figure 2 Schematic diagram of the structure of the rheometer of the present invention Figure 1 ;

[0054] Figure 3Schematic diagram of the structure of the rheometer of the present invention Figure 2 ;

[0055] Figure 4 Structural block diagram of the concrete rheological properties feedback control system of the present invention.

[0056] In the figure: 1. outer cylinder; 2. stirring blade; 3. support plate; 4. motor; 5. reducer; 6. coupling; 7. anti-slip strip; 8. bottom cover; 9. hopper. DETAILED DESCRIPTION

[0057] 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.

[0058] like Figure 1-4 As shown, a method for testing the rheological properties of concrete comprises the following steps:

[0059] S1. Load the fresh concrete sample to be tested into the outer cylinder of the rheometer, the inner diameter of the outer cylinder of the rheometer is R0;

[0060] S2. The torque and speed sensors of the rheometer are used to measure the torque T and speed N of the mixing blade when the concrete is rotating in real time;

[0061] S3. When the stirring blade of the rheometer rotates, it forms a radius R with the concrete inside. i The height of the stirring blade is h;

[0062] S4. The rheometer host applies a plurality of different stirring blade rotation speeds N, and obtains the torque T at the rotation speed;

[0063] Calculate the rheological parameter SWI according to the following steps (a) to (m):

[0064] (a) Fit the relationship between variable T and variable N according to formula (1), and obtain parameter G by least square method or software calculation HB , H HB and J;

[0065] T=G HB +H HB N J (1)

[0066] G HB is the flow resistance of HB type fluid (N·m), H HB is the viscosity coefficient of HB type fluid (N·m·s)

[0067] (b) Calculate the initial Herbach fluid parameter yield stress τ according to formulas (2) to (4) 0,HB , flow index n and consistency coefficient K;

[0068]

[0069] n=J (3)

[0070]

[0071] (c) Determine the critical radius R at the boundary between the static area and the moving area according to formula (5): p ;

[0072] R p =(T / 2πhτ 0,HB ) 1 / 2 (5)

[0073] (d) Calculate the corrected speed N obtained from the rheological parameters according to formula (6) or (7): mod , where R p ≤R o When Rp>Ro, use formula (6); when Rp>Ro, use formula (7);

[0074]

[0075] (e) According to formula (8), the seven groups of test speeds N described in step (1) and the correction speeds N described in step (d) are calculated. mod Calculate the root mean square error RMSE;

[0076]

[0077] (f) Change the rheological parameter τ 0,HB , K, n, repeat the above steps until the rheological parameter τ with the minimum RMSE is obtained 0,HB , K, n, can be achieved through the planning and solving function of Excel.

[0078] (g) Use formula (9) to determine the initial μ value.

[0079]

[0080] Where n and K are the values ​​determined in step (f), is the maximum shear rate.

[0081] (h) Use formula (10) or formula (11) to calculate the corrected speed Ω MOD , where R p ≤R o When using formula (10), R p>Ro, use formula (11);

[0082]

[0083] (i) calculating the rotation speed Ω calculated in step (a) according to formula (12);

[0084] Ω=2πN (12)

[0085] (j) for 7 groups of the rotation speed Ω described in step (j) and the modified rotation speed Ω described in step (i) MOD Calculate the root mean square error (RMSE).

[0086] Calculate the root mean square error (RMSE) according to formula (12);

[0087]

[0088] (k) Change the rheological parameter μ and repeat the above steps until the rheological parameter μ with the minimum RMSE is obtained, which can be achieved through the planning and solving function of Excel;

[0089] (l) Use step (f) to obtain τ 0,HB Let τ0 be τ0, and use μ obtained in step (k) to calculate the shear work parameter SWI according to formula (14).

[0090]

[0091] Where: s, ρ and a are three preset constants. s is the shear motion distance, which can be selected according to the amplitude of the vibrating rod; ρ is the concrete density, obtained by the test; a is the shear motion acceleration, which can be selected according to the vibration acceleration amplitude.

[0092] A concrete rheological property feedback control system comprises the rheometer in the above-mentioned test method, wherein the rheometer comprises an outer cylinder, a support plate and a bottom cover, wherein the outer cylinder is a cylinder that passes through from top to bottom, the support plate is provided with the top of the outer cylinder, the support plate is clamped with the upper edge of the outer cylinder, the bottom cover is provided at the bottom of the outer cylinder, the bottom cover can be opened and closed, and when opened, the concrete contained in the outer cylinder can be released, and a plurality of anti-slip strips running up and down are evenly arranged on the inner wall of the outer cylinder, and the anti-slip strips are used to prevent the concrete from contacting with the inner wall of the outer cylinder when the rheometer is working. In order to avoid the calculation error caused by relative sliding, the motor, reducer and coupling are arranged from top to bottom on the support plate, and the motor, reducer and coupling are connected in sequence. A stirring blade is arranged inside the outer cylinder, and the shaft of the stirring blade is coaxially arranged with the outer cylinder. The stirring blade has a cross-shaped cross section, and the stirring blade is detachably connected to the coupling. A hopper connected to the inner part of the outer cylinder is arranged on the upper edge of the outer cylinder, and the hopper extends obliquely outward. The feed hopper is trumpet-shaped, large outside and small inside, so as to facilitate the loading of concrete. The inner diameter of the outer cylinder is Ro. When the stirring blade rotates, it forms a radius of R together with the concrete inside it. i The height of the stirring blade is h.

[0093] The method further includes a sensor module, wherein the sensors include a torque sensor and a speed sensor; a control host module, wherein the torque sensor and the speed sensor are communicatively connected to the control host, and the torque T and the speed N of the stirring blade during rotation are measured in real time to the control host, and the control host calculates the rheological parameter SWI according to steps (a) to (l) in the above-mentioned test method; a feedback control module and a vibrating device, wherein the control host is communicatively connected to the feedback control module, and the feedback control module is electrically connected to the vibrating device, and the control host calculates the vibration time according to the rheological parameters, and controls the vibration time of the vibrating device through the feedback control module.

[0094] It also includes a remote control module, and the control host is wirelessly connected to the remote control module. Through WiFi or Bluetooth connection, the remote control module remotely obtains rheological parameter data and vibration time data, and remotely controls the vibration time of the vibration equipment through the remote control module.

[0095] A method for applying the concrete rheological property test method in concrete vibration comprises the following steps:

[0096] Establish the corresponding relationship between SWI value and vibration time t: t=k·SWI+b.

[0097] Example 1

[0098] The rheometer with the above structure was used to test three concrete models with different proportions using a 7-level speed gradient. The height of the mixing blade of the rheometer was h = 127 mm, and the inner diameter of the outer cylinder was Ro = 143 mm. When the mixing blade rotated, it formed a cylinder with a radius of Ri = 63.5 mm together with the concrete inside it.

[0099] The concrete mix ratios of the three types are shown in Table 1.

[0100]

[0101] Table 1. Concrete mix ratio

[0102] According to the actual data in the project, s, ρ and a are determined as the three preset constant values. s is the shear movement distance, which can be selected according to the amplitude of the vibrating rod; ρ is the concrete density, obtained by the test; a is the shear movement acceleration, which can be selected according to the vibration acceleration amplitude.

[0103] s=0.0003~0.0005m, ρ=2350~2450kg / m 3 , a=10~15g

[0104] The vibration amplitude is 0.5 mm, and the movement distance corresponding to one vibration is 0.0005 m. Under normal circumstances, the density of concrete is usually between 2350 and 2450 kg / m 3 , here it is taken as 2400kg / m 3 The actual vibration acceleration in the project is about 10-15g, which is taken as 10g here, i.e. 98m / s 2 .

[0105] The experimental data of SWI values ​​of concrete with three types of mix ratios are shown in Table 2.

[0106]

[0107] Table 2. Comparison of SWI values ​​and slump expansion of concrete with different mix ratios

[0108] According to the data in Table 2, as the strength grade of concrete continues to increase, the plastic viscosity of concrete gradually increases. At the same time, under the condition that the slump spread is slightly reduced and the yield stress is slightly increased, the SWI value calculated by this rheological property test method continues to increase. SWI reflects the amount of work required per unit area for the concrete fluid to move a certain distance under a certain acceleration under the action of shear force. The larger the value, the more difficult it is to make the concrete accelerate, that is, the worse the fluidity. This parameter SWI is negatively correlated with the slump spread.

[0109] Example 2

[0110] Using the C40 concrete prepared in Example 1, three rheological parameter repeatability verification experiments were performed according to the parameter values ​​in Example 1. The verification experimental data are shown in Table 3.

[0111] Test batch τ0(Pa) μ(Pa·s) <![CDATA[SWI(J / m 2 )]]> 1 1068±9 109±2 1.81±0.019 2 1061±7 105±1 1.79±0.005 3 1073±10 106±3 1.80±0.015

[0112] Table 3. Rheological parameter test repeatability verification data (C40 concrete)

[0113] According to the data in Table 3, the final calculated SWI values ​​of three different batches of C40 concrete are basically consistent with small deviations, which proves the reliability and consistency of the calculation method of this parameter SWI.

[0114] Example 3

[0115] The corresponding relationship between SWI value and vibration time t is established: t=k·SWI+b. The values ​​of k and b are determined according to the vibration time parameters of the actual concrete in the project. The vibration time is calculated according to the SWI values ​​of concrete with three different proportions in Example 1.

[0116] After trial operation, the vibration-free concrete meets the requirements of yield stress not exceeding 50Pa, plastic viscosity not exceeding 100Pa·s, and vibration time of 0. The SWI value calculated by the above test method is 1.25. For another type of concrete, when the yield stress is 1500Pa and the plastic viscosity is 250Pa·s, the vibration time is 30s, and the SWI value at this time is calculated to be 2.69. Substituting the above two sets of numbers into the formula t=k·SWI+b, we can get k=20.8b=-26.0. Then, the formula t=20.8SWI-26.0 can be used to calculate that the vibration times corresponding to concrete mix ratios 01, 02, and 03 are 19.3s, 11.9s, and 6.4s, respectively, as shown in Table 4.

[0117]

[0118] Table 4. SWI value and vibration time of concrete with different mix ratios

[0119] According to the data in Table 4, the vibration time is positively correlated with the SWI value, so the vibration time of a certain type of concrete can be determined by SWI.

[0120] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for testing the rheological properties of concrete, characterized in that: The method comprises the following steps: S1. placing a fresh concrete sample to be tested into the outer cylinder of the rheometer, wherein the inner diameter of the outer cylinder of the rheometer is R0; S2. The torque and speed sensors of the rheometer are used to measure the torque T and speed N of the mixing blade when the concrete is rotating in real time; S3. When the stirring blade of the rheometer rotates, it forms a radius R with the concrete inside. i The height of the stirring blade is h; S4. The rheometer host applies a plurality of different stirring blade rotation speeds N, and obtains the torque T at the rotation speed; Calculate the rheological parameter SWI according to the following steps (a) to (m): (a) According to formula (1), fit the relationship between variable T and variable N to obtain parameter G HB , H HB and J; T=G HB +H HB N J (1) (b) Calculate the initial Herbach fluid parameter yield stress τ according to formulas (2) to (4) 0,HB , flow index n and consistency coefficient K; (c) Determine the critical radius R at the boundary between the static area and the moving area according to formula (5): p ; R p =(T / 2πhτ 0,HB ) 1 / 2 (5) (d) Calculate the corrected speed N obtained from the fluid parameters according to formula (6) or (7): mod , where R p ≤R o When Rp>Ro, use formula (6); when Rp>Ro, use formula (7); (e) According to formula (8), the seven groups of test speeds N described in step (1) and the correction speeds N described in step (d) are calculated. mod Calculate the root mean square error RMSE; (f) Change the rheological parameter yield stress τ 0,HB , flow index n and consistency coefficient K, repeat the above steps until the rheological parameter yield stress τ with the minimum RMSE is obtained 0,HB , flow index n and consistency coefficient K; (g) Determine the initial μ value using formula (9); Where n and K are the values ​​determined in step (f), is the maximum shear rate; (h) Use formula (10) or formula (11) to calculate the corrected speed Ω MOD , where R p ≤R o When using formula (10), R p >Ro, use formula (11); (i) calculating the rotation speed Ω calculated in step (a) according to formula (12); Ω=2πN (12) (j) for 7 groups of the rotation speed Ω described in step (j) and the modified rotation speed Ω described in step (i) MOD Calculate the root mean square error RMSE; Calculate the root mean square error (RMSE) according to formula (12); (k) changing the rheological parameter μ and repeating the above steps until the rheological parameter μ with the minimum RMSE is obtained; (l) Use step (f) to obtain τ 0,HB is τ0, and the shear work parameter SWI is calculated according to formula (14) using μ obtained in step (k); Wherein: s, ρ and a are three preset constants; s is the shear motion distance, which is selected according to the amplitude of the vibrating rod; ρ is the density of concrete; a is the shear motion acceleration, which is selected according to the amplitude of the vibration acceleration.

2. An application of shear work parameter SWI in concrete vibration in a concrete rheological property test method, wherein the SWI value is calculated by the method as claimed in claim 1, characterized in that: The following steps are involved: Establish the corresponding relationship between SWI value and vibration time t: t = k·SWI + b (15) Early experiments were conducted with concrete of different mix proportions to test the actual vibration time of concrete of two mix proportions and calculate the SWI values ​​of concrete of different mix proportions; Substitute multiple sets of data into formula (15) to calculate the values ​​of k and b, and determine the vibration time of the concrete to be tested through the SWI value.

3. A feedback control system for testing rheological properties of concrete, characterized by: The rheometer comprises the rheometer as claimed in claim 1, and also comprises a sensor module, a control host module, a feedback control module and a vibrating device, wherein the sensors comprise a torque sensor and a speed sensor; the torque sensor and the speed sensor are communicatively connected to the control host, and the real-time measured torque T and speed N of the stirring blade during rotation are transmitted to the control host, and the control host calculates the rheological parameter SWI according to steps (a) to (l) in the test method; the control host is communicatively connected to the feedback control module, and the feedback control module is electrically connected to the vibrating device, and the control host calculates the vibration time according to the steps in the application based on the rheological parameter SWI, and controls the vibration time of the vibrating device through the feedback control module.

4. A feedback control system for testing rheological properties of concrete according to claim 3, characterized in that: It also includes a remote control module, the control host is wirelessly connected to the remote control module, the remote control module remotely obtains rheological parameter data and vibration time data, and remotely controls the vibration time of the vibration equipment through the remote control module.

5. A feedback control system for testing rheological properties of concrete according to claim 3, characterized in that: The rheometer comprises an outer cylinder, a support plate and a bottom cover. The outer cylinder is a cylinder that passes through from top to bottom. The support plate is provided with the top of the outer cylinder, and the support plate is clamped on the upper edge of the outer cylinder. The bottom cover is provided at the bottom of the outer cylinder, and the bottom cover can be opened and closed. A plurality of anti-slip strips running up and down are evenly distributed on the inner wall of the outer cylinder. A motor, a reducer and a coupling are arranged in sequence from top to bottom above the support plate, and the motor, the reducer and the coupling are connected in sequence. A stirring blade is arranged inside the outer cylinder, and the axis of the stirring blade is coaxially arranged with the outer cylinder. The stirring blade has a cross-shaped cross-section, and the stirring blade is detachably connected to the coupling. A hopper connected to the inside of the outer cylinder is arranged at the upper edge of the outer cylinder.

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