Concrete comprehensive working performance online monitoring system and method

Abstract

The invention provides an on-line monitoring system for comprehensive working performance of concrete. The on-line monitoring system comprises a concrete drainage device located on a concrete conveying line of a mixing station and a construction bin surface; the detection container is used for collecting concrete and detecting the working performance, and a plurality of detection channels of which the bottoms are communicated with one another are arranged in the detection container; the gate group is used for controlling connection and disconnection of concrete among the passages; the sensing unit is used for measuring the quality of the concrete in the detection container and the liquid level height of the concrete in each detection channel; the data processing and equipment control terminal is used for controlling the gate group, calculating a series of indexes of the concrete according to the data measured by the sensing unit, taking the indexes as detection results, performing abnormal alarm on the detection results, storing and sending the measured data and the detection results; and the cloud platform communicates with the data processing and equipment control terminal. According to the invention, on-line in-situ monitoring, rapid evaluation and alarm feedback of various working performances of concrete can be realized under the condition that on-site pouring construction is not influenced.

Description

Technical Field

[0001] The present invention belongs to the technical field of concrete working performance detection, and in particular relates to an online monitoring system and method for comprehensive concrete working performance. Background Art

[0002] Concrete is one of the most widely used building materials. It is made by mixing water, cement, fly ash, sand and gravel aggregates and admixtures in a certain proportion. The concrete that is still in a plastic flow state is called self-compacting concrete. The working performance of self-compacting concrete is directly related to the uniformity and density of concrete after casting, which in turn has a significant impact on the construction quality and service life of the engineering structure. The main working properties of self-compacting concrete include: fluidity (plasticity), viscosity, uniformity, gap passability, density, etc. There are specific regulations and methods for testing and evaluating the working performance of concrete mixtures in national, industry, local, and group standards.

[0003] However, there are the following problems in testing the working performance of self-compacting concrete by existing means:

[0004] (1) Existing testing means and methods require dedicated personnel to manually conduct multiple tests to obtain comprehensive performance evaluation, which is not only time-consuming and labor-intensive, but also the effectiveness and reliability of the results depend on the level of the test personnel;

[0005] (2) Existing automated detection methods and devices for concrete working performance are mostly independent of the concrete mixing, production and transportation process and cannot be organically integrated with the existing concrete production-transportation system. Forced integration may interfere with and affect on-site construction.

[0006] (3) Due to the limitation of detection methods, the on-site comprehensive detection of concrete working performance can only be carried out by regular sampling (usually once every 4 / 8 hours). The detection efficiency and frequency are low, and it is difficult to reflect the actual working performance of concrete;

[0007] (4) Due to the variability of the raw materials themselves, the working performance of on-site self-compacting concrete is always changing dynamically. There is a lack of real-time online quantitative detection methods, making it difficult to conduct real-time alarm feedback and dynamic adjustments, and the working performance of concrete is not guaranteed;

[0008] In view of the above-mentioned problems, based on the idea of ​​diversion detection and aggregate recovery, the present invention proposes an online monitoring system and method for the comprehensive working performance of concrete, which can realize online, automatic, fast and comprehensive detection and evaluation and alarm feedback of the comprehensive working performance of concrete on site without affecting the on-site construction, and solve the current problems of low efficiency and frequency of concrete working performance detection, weak representativeness of detection results, inability to provide real-time alarm and dynamic feedback, waste of manpower and material resources and poor result stability. Summary of the invention

[0009] The present disclosure aims to solve at least one of the technical problems in the related art.

[0010] The present invention provides an online monitoring system and method for comprehensive working performance of concrete, which can realize automatic online in-situ monitoring, rapid evaluation and alarm feedback of various working performances of concrete without affecting on-site pouring construction, and provide real-time feedback to guide the mixing production and proportion adjustment of concrete.

[0011] In order to achieve the above objectives, the present disclosure adopts the following technical solutions:

[0012] The first aspect of the present disclosure provides an online monitoring system for comprehensive concrete working performance, comprising:

[0013] Concrete diversion device, located on the concrete transportation line between the mixing station and the construction warehouse, is used to guide part or all of the concrete for working performance testing;

[0014] A detection container is located below the concrete drainage device and is used for collecting concrete and detecting working performance; a plurality of detection channels interconnected at the bottom are provided inside the detection container, one of the detection channels is used as a feed channel, and the concrete drawn out from the concrete drainage device enters the detection container through the feed channel;

[0015] Aggregate equipment, located below the detection container, for recovering the tested concrete discharged from the detection container and transporting it to the construction warehouse surface;

[0016] A gate group, used to control the on and off of concrete between each passage during the operation of the online monitoring system;

[0017] A sensing unit, used to measure the mass of concrete in the detection container and the liquid level of concrete in each detection channel in the detection container;

[0018] A data processing and equipment control terminal is used to control the gate group; calculate a series of indicators of concrete according to the data measured by the sensor unit as the test results of the comprehensive working performance of concrete and make abnormal alarms for the test results of the comprehensive working performance of concrete, as well as store and send the measurement data and test results, wherein the series of indicators include a combination of any multiple indicators of the fluidity, viscosity, uniformity and apparent density of concrete;

[0019] An equipment bracket, used for installing and arranging the concrete drainage device, the detection container, the gate group, the sensor unit and the data processing and equipment control terminal;

[0020] The cloud platform communicates with the data processing and device control terminal to archive, analyze and push alarms for the measurement data or test results transmitted by the data processing and device control terminal, and sends the archived data and alarm information to the user end on time or by event according to user needs.

[0021] In some embodiments, the concrete drainage device includes a drainage storage container, a drainage channel, a drainage discharge port, an overflow channel, and an overflow return channel;

[0022] The drainage channel is connected between the fresh concrete unloading channel or unloading point located near the online monitoring system and the upper part of the drainage storage container, and the fresh concrete prepared by the mixing station is transported to the fresh concrete unloading channel or unloading point through a chute or a concrete tanker;

[0023] The overflow channel is used to discharge the concrete exceeding the volume limit in the drainage storage container and transport it to the aggregate equipment through the overflow return channel. The overflow return channel is also used to transport the concrete that has not participated in the inspection and is transported from the fresh concrete discharge channel or discharge point to the aggregate equipment;

[0024] The drainage and discharge port is connected between the drainage and storage container and the feeding channel of the detection container.

[0025] In some embodiments, the volume limit is 0.8 to 1.2 times the concrete required for a single test of the detection container; the inclination angle α of the overflow channel is 30° to 80°; the upper part of the drainage and discharge port is set to be gradually narrowed, the inclination angle γ is not less than 50°, and the minimum side length of the cross section of the drainage and discharge port is not less than 5 times the maximum aggregate particle size of the concrete;

[0026] The drainage storage container is also provided with an isolation screen placed obliquely and connected to the overflow channel to prevent unevenly mixed concrete blocks from entering the drainage discharge port. The aperture of the isolation screen is 3 to 10 times the maximum aggregate particle size of the concrete, and the inclination angle β of the isolation screen is 20° to 50°.

[0027] In some embodiments, the interior of the detection container is divided into a plurality of detection channels by a plurality of partitions, the partition spacing is set to be adjustable, the minimum side length of the cross section of any detection channel is not less than 5 times the maximum aggregate particle size of concrete, and the height is not less than 10 times the maximum aggregate particle size of concrete; a detection channel located at the outermost or middle of the detection container is selected as the feed channel, and the cross-sectional area of ​​the feed channel is not less than 1.5 times that of other detection channels.

[0028] In some embodiments, a detection discharge port is provided at the bottom of the detection container, and the detection discharge port consists of a gradually narrowing inclined section and a parallel extension section connected to its lower part, the inclination angle θ of the inclined section is 40°~70°, the cross-section of the detection discharge port is a circle or a regular polygon, the diameter of the parallel extension section is not less than 5 times the maximum aggregate particle size of the concrete; the length of the parallel extension section is not less than 3 times the maximum aggregate particle size of the concrete.

[0029] In some embodiments, the gate group includes a drainage gate arranged at the feed port of the concrete drainage device, a feed gate arranged at the discharge port of the concrete drainage device for controlling the amount of concrete loaded into the detection container, and a discharge gate arranged at the discharge port of the detection container; when the detection container is in the feeding stage, the discharge gate remains closed and the feed gate remains open; when the concrete in the detection container reaches a set amount, the discharge gate and the feed valve are both kept closed, and the detection container is in a static stage; when the liquid level of concrete in each detection channel of the detection container tends to be constant, the detection container enters the discharge stage, the discharge gate is opened, and the feed gate remains closed; the drainage gate is in a normally open state during the detection process, and is only in a closed state when the current batch of concrete does not participate in the detection.

[0030] In some embodiments, the sensing unit includes a weight sensor and a liquid level measuring component; the weight sensor is arranged at the bottom of the detection container; the liquid level measuring component adopts a liquid level sensor group or an image recognition module, the liquid level sensor group is composed of a plurality of liquid level sensors, and each liquid level sensor is respectively arranged directly above a corresponding detection channel in the detection container; the image recognition module acquires the image of each detection channel by adding scale lines on the transparent outer wall of each detection channel in combination with a camera and uses an image recognition algorithm to measure the concrete liquid level height.

[0031] In some embodiments, the sensing unit further comprises a temperature sensor provided on the inner wall or the outer wall of the detection container for monitoring the temperature of the concrete outlet.

[0032] In some embodiments, the data processing and equipment control terminal calculates the fluidity index I of the concrete according to the liquid level height of the concrete in each detection channel of the detection container at the start of unloading collected by the sensor unit. f and the apparent density ρ c0 According to the concrete mass data collected by the sensing unit in the unloading stage of the detection container, the concrete unloading mass-time curve is obtained, and the viscosity index of the concrete is calculated. v and Uniformity Indicator UI c .

[0033] In some embodiments, the data processing and equipment control terminal calculates the fluidity index of concrete according to the following formula: f and the apparent density ρ c0 :

[0034]

[0035] in, is the liquid level of concrete in each detection channel of the detection container at the beginning of unloading, k is the detection channel number, k=1~K, K is the number of detection channels provided in the detection container, f() is the quantitative relationship between the fluidity index and the liquid level of each detection channel established based on theoretical calculation and indoor test; V equ To detect the internal volume of the container, S k is the cross-sectional area of ​​the kth detection channel, is the upper edge height of the kth detection channel, is the distance from the liquid surface of concrete in each detection channel to the upper edge of each detection channel;

[0036] The data processing and equipment control terminal calculates the viscosity index I of the concrete according to the following formula: v :

[0037]

[0038] in, is the average unloading rate during the uniform unloading period, t1 and m1 are the initial time and initial unloading mass of the uniform unloading period, respectively, t n and m n are the final time of the uniform unloading period and the final unloading mass, respectively; g( ) is the quantitative relationship between the viscosity index and the average unloading rate established based on theoretical calculations and indoor experiments;

[0039] The data processing and equipment control terminal uses any of the following three formulas to calculate the uniformity index UI of concrete: c :

[0040]

[0041] Among them, m i and m i+1 are the concrete discharge masses at the i-th and i+1-th record values ​​in the uniform discharge period, t i and t i+1 are the time of the i-th and i+1-th recorded values ​​in the uniform unloading period respectively; is the estimated value of the concrete discharge mass at the time corresponding to the i-th record value, which is obtained by linearly fitting the data of the uniform discharge period in the concrete discharge mass-time curve: Calculate the estimate.

[0042] In some embodiments, an obstacle steel bar for detecting the gap passability index of concrete is arranged in the feed channel, and the data processing and equipment control terminal determines whether the feed channel is blocked according to the liquid level of concrete in the feed channel collected by the sensor unit to calculate the gap passability index, and the formula is as follows:

[0043]

[0044] Among them, δ pass It is an index of the gap permeability of concrete.

[0045] In some embodiments, the online monitoring system further comprises an alarm disposed at the mixing station;

[0046] The alarm push types of the cloud platform are divided into abnormal concrete working performance alarms and abnormal equipment alarms; the alarm push of the cloud platform adopts a probabilistic risk mechanism. When an abnormality is detected and the risk probability is greater than the design threshold, an alarm reminder is issued through the user terminal and the alarm.

[0047] The second aspect of the present disclosure provides an online monitoring method of the online monitoring system according to any embodiment of the first aspect of the present disclosure, comprising the following steps:

[0048] Step S1, before the mixing station starts to produce concrete, firstly, the sensor unit is set to zero, and the inner wall of the detection container and the connecting pipe thereof are moistened with clean water;

[0049] Step S2: when the mixing station produces concrete, the data acquisition and equipment control terminal is turned on, the opening and closing state of the gate group is initialized, and part or all of the fresh concrete delivered by the mixing station enters the detection container, and the concrete that does not enter the detection container enters the aggregate equipment;

[0050] Step S3: Record the mass m of the concrete to be tested entering the detection container and the liquid level of the concrete in each detection channel in real time through the sensor unit. and transmit it to the data acquisition and equipment control terminal;

[0051] Step S4: When the mass m of the concrete in the detection container is greater than the mass threshold m0, or the liquid level of the concrete in the feed channel reaches the set height threshold, all gates in the gate group are closed and left to stand for a period of time so that the liquid level of the concrete in each detection channel tends to remain unchanged. This is taken as the initial state before unloading, and the liquid level of the concrete in each detection channel at this time is recorded. and the mass of concrete in the test container m c0 ;

[0052] Step S5: The detection container is unloaded through the gate assembly, and the mass m(t) of the concrete to be tested in the detection container and the liquid level of the concrete in each detection channel are recorded in real time through the sensor unit during the unloading process. t represents time;

[0053] Step S6: After all the concrete in the detection container is discharged, the data acquisition and equipment control terminal records the and m c0 Calculation of concrete fluidity index I f and the apparent density ρ c0 According to the m(t) measurement curve measured by the sensor unit during the unloading process, the viscosity index I of the concrete is calculated. v and Uniformity Indicator UI c The calculated working performance indicators, including the working performance indicators, are uploaded to the cloud platform as test results together with the measurement data collected by the sensor unit;

[0054] Step S7, the cloud platform performs data archiving, data analysis and alarm push on the data uploaded by the data acquisition and device control terminal, and the results are pushed to the user end in real time;

[0055] Step S8: If the current on-site pouring is not finished, return to step S2 and continue the next concrete test; if the current on-site pouring is finished, clean the test container and wait for the next startup test.

[0056] Compared with the prior art, the present invention has the following characteristics and beneficial effects:

[0057] (1) The present disclosure can obtain quantitative indicators of various working properties of concrete mixtures, such as fluidity (plasticity), cohesion, anti-segregation, gap passability and uniformity, through a single test, and they can be interpreted in a complementary manner. For example, when the unloading time is too long, the working properties of the concrete can be accurately inferred based on its unloading uniformity and gap passability, and the disclosure can be applied to different types of concrete.

[0058] (2) The structure of the present invention is simple and flexible, and can realize online automatic unmanned monitoring of concrete working performance.

[0059] (3) The present disclosure can be combined with the concrete production process to achieve real-time detection, rapid evaluation and alarm feedback of the working performance of the concrete mixture without interfering with the construction, and real-time feedback can guide the mixing production of concrete.

[0060] (4) The present invention is simple and fast, with a single test and evaluation taking 2 to 5 minutes. 96 to 240 tests can be performed per shift (8 hours), far exceeding the number of tests specified in current specifications, and can better reflect the actual working performance of concrete mixtures.

[0061] (5) The present disclosure can measure various working performance indicators of concrete, such as fluidity (plasticity), cohesion, anti-segregation, gap passability and uniformity, at one time, and they can complement each other; for example, when the unloading time is too long, the working state of the concrete can be accurately inferred based on its unloading uniformity and gap passability. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 It is a schematic diagram of the overall structure of an online monitoring system for comprehensive working performance of concrete provided by an embodiment of the first aspect of the present disclosure;

[0063] Figure 2 yes Figure 1 The side view and top view of the concrete drainage device in the online monitoring system shown;

[0064] Figure 3 yes Figure 1 The schematic diagram of the detection principle of the detection container in the online monitoring system shown;

[0065] Figure 4 The second aspect of the present disclosure provides an embodiment based on Figure 1 A flow chart of an online monitoring method of the monitoring system shown;

[0066] Figure 5 It is a monitoring curve of the concrete mass in the detection container and the distance from the concrete liquid level in each detection channel to the upper edge of the detection container during the feeding, static and unloading processes obtained in the embodiment of the present disclosure. DETAILED DESCRIPTION

[0067] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0068] On the contrary, the present application covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present application as defined by the claims. Further, in order to make the public have a better understanding of the present application, some specific details are described in detail in the detailed description of the present application below. Those skilled in the art can fully understand the present application without the description of these details.

[0069] See also Figure 1 , Figure 2The first aspect of the present disclosure provides an online monitoring system for comprehensive concrete working performance, comprising:

[0070] The concrete drainage device 1 is located on the concrete transportation route between the mixing station and the construction warehouse surface, and is used to guide part or all of the concrete for working performance testing;

[0071] The detection container 2 is located below the concrete drainage device 1 and is used for collecting concrete and detecting working performance. A plurality of detection channels interconnected at the bottom are provided inside the detection container 2, one of which serves as a feed channel 21, through which the concrete drawn out from the concrete drainage device 1 enters the detection container 2.

[0072] The material collecting device 10 is located below the detection container 2 and is used to recover the tested concrete discharged from the detection container 2 and transport it to the construction warehouse surface;

[0073] Gate group 3, used to control the on-off of concrete between each passage during the operation of the online monitoring system of this embodiment;

[0074] The sensor unit 4 is used to measure the mass of the concrete in the detection container 2 and the liquid level of the concrete in each channel of the detection container 2;

[0075] A data processing and equipment control terminal 5, which is connected to the gate group 3 and the sensor unit 4, and is used to control the gate group 3; calculate a series of indicators of concrete according to the data measured by the sensor unit 4, as the test results of the comprehensive working performance of concrete, and perform abnormal alarms for the test results of the comprehensive working performance of concrete, as well as store and send the measurement data and test results, the series of indicators including any combination of multiple indicators of the fluidity, viscosity, uniformity and apparent density of concrete;

[0076] Equipment bracket 6, used for installing and arranging concrete drainage device 1, detection container 2, gate group 3, sensor unit 4 and data processing and equipment control terminal 5;

[0077] The cloud platform 7 communicates with the data processing and device control terminal 5 to archive, analyze and push alarms for the measurement data or test results transmitted by the data processing and device control terminal 5, and sends the archived data and alarm information to the user end on time or by event according to user needs.

[0078] In some embodiments, the equipment bracket 6 is a frame structure composed of several components. The components of the frame structure are preferably made of rust-resistant, strong and easy-to-clean alloy materials, and are connected and fastened by bolting for easy disassembly; the equipment bracket 6 is provided with fixed positions for the concrete drainage device 1, the detection container 2, the gate group 3, the sensor unit 4 and the data processing and equipment control terminal 5; the equipment bracket 6 is preferably an independent, integral form separated from the ground, which is convenient for lifting and movement.

[0079] In some embodiments, see Figure 2The concrete drainage device 1 includes a drainage storage container 12, an isolation screen 15 arranged inside the drainage storage container 12, a drainage channel 11, a drainage discharge port 13 and an overflow channel 14 respectively connected to the upper, lower and side parts of the drainage storage container 12, and an overflow return channel 16 connected to the aggregate device 3. The drainage channel 11 is used to guide part or all of the concrete transported by the fresh concrete unloading channel or unloading point located near the online monitoring system of this embodiment into the drainage storage container 12, and the fresh concrete prepared by the mixing station is transported to the fresh concrete unloading channel or unloading point through a chute or a concrete tanker. The drainage storage container 12 is used to collect and store a part of the concrete during the detection process, waiting for the next detection, while also avoiding interference with the detection process and results. The overflow channel 14 is used to discharge the concrete exceeding the volume limit in the drainage storage container 12 and transport it to the aggregate equipment 10 through the overflow return channel 16 to avoid pollution and waste caused by concrete overflow. The overflow return channel 16 is also used to transport the concrete that does not participate in this test and is transported from the fresh concrete unloading channel or unloading point to the aggregate equipment 10; the aforementioned volume limit is usually taken as 0.8 to 1.2 times the concrete required for a single test of the test container 2 to ensure that there is sufficient concrete for each test; the inclination angle α of the overflow channel 14 is 30° to 80° to avoid clogging of concrete in the overflow channel 14. The drainage and discharge port 13 is connected between the lower part of the drainage storage container 12 and the upper part of the feed channel 21 in the detection container 2. The upper part of the drainage and discharge port 13 is set to be gradually narrowed, and the inclination angle γ is not less than 50°. According to practical experience, if the inclination angle γ<45°, when the viscosity of the concrete is high, it is easy to produce wall hanging phenomenon, so that the concrete is deposited in the drainage and discharge port 13, and finally the drainage and discharge port 13 is blocked, affecting the normal operation of the equipment; the minimum side length of the cross section of the drainage and discharge port 13 is not less than 5 times the maximum aggregate particle size of the concrete. The isolation screen 15 is tiltedly arranged inside the drainage storage container 12, mainly used to block the unmixed concrete lumps and guide them back to the overflow reflux channel 16 through the overflow channel 14, so as to avoid the blockage of the detection container 2 and the fluctuation of the detection result; the aperture setting of the isolation screen 15 should be determined according to the concrete type and mix ratio. Generally, it should be set to 3 to 10 times the maximum aggregate particle size of the concrete to be tested, so as to avoid excessive aggregates or concrete lumps from entering the detection container 2 and affecting the detection results; the inclination angle β of the isolation screen 15 (that is, the angle between the isolation screen 15 and the horizontal plane) should be set to 20° to 50°, so that the screened excessive aggregates or concrete lumps can be discharged from the drainage storage container 12 along the set direction.

[0080] In some embodiments, the structure of the detection container 2 is a multi-channel interconnected container with interconnected bottoms. The main body of the detection container is made of a rust-resistant, strong, and easy-to-clean alloy material or a transparent material, such as a transparent acrylic plate, to facilitate visualization of the detection process. The interior of the detection container 2 is divided into a number of detection channels interconnected at the bottom by a number of partitions. The number K of detection channels, the size of detection channels, the volume of the detection container, and the specific structure should be determined according to the type of concrete to be tested and the single detection volume. A number of slots that match the partitions are formed on the inner side wall of the detection container 2. By inserting the partitions into different slots, the width of the detection channel can be adjusted to adapt to different types of concrete, and the minimum side length of the cross section of any detection channel is not less than 5 times the maximum aggregate particle size of the concrete, and the height is not less than 10 times the maximum aggregate particle size of the concrete. For self-compacting concrete with good fluidity, the detection channel can be set to a narrow and long form by adjusting the partition arrangement. The number of channels is 4 to 8, and the cross-sectional size of the channel is 5 to 8 times the maximum aggregate particle size of the concrete, generally 8cm to 16cm; for ordinary concrete with poor fluidity, the partition arrangement can be adjusted to set a wider detection channel. The number of detection channels is 3 to 5, and the cross-sectional size of the detection channel is 5 to 10 times the maximum aggregate particle size of the concrete, generally 10cm to 20cm.

[0081] Furthermore, the outermost detection channel or the middle detection channel in the detection container 2 is generally set as the feed channel 21, and the cross-sectional area of ​​the feed channel 21 is not less than 1.5 times that of other detection channels to avoid concrete clogging; a short partition 22 should be added to the upper part of the feed channel 21 to prevent concrete splashing from affecting the reading of the sensor used to measure the liquid level of concrete in the channel in the sensing unit 4; since the feed channel 21 has a larger cross-sectional area than other detection channels, an obstacle steel bar 23 can be set in the feed channel 21 to detect the gap passability of concrete. The obstacle steel bar 23 is set close to the bottom end of the feed channel 21, and the distance between two adjacent obstacle steel bars 23 is generally set to 2 to 3 times the maximum aggregate particle size of the concrete, usually 4 cm to 6 cm, to simulate a narrower filling or circulation channel.

[0082] Furthermore, a detection discharge port 24 is provided at the bottom of the detection container 2. The detection discharge port 24 adopts a gradually narrowing form, the inclination angle θ of the inclined section is 40°~70°, and the cross-section of the detection discharge port 24 is a circle or a regular polygon; a parallel extension section needs to be provided at the lower end of the inclined section of the detection discharge port 24 to control the concrete discharge flow rate. The diameter of the parallel extension section is not less than 5 times the maximum aggregate particle size of the concrete, and can be set to 5~8 times the maximum aggregate particle size of the concrete. The length of the parallel extension section is not less than 3 times the maximum aggregate particle size of the concrete.

[0083] In some embodiments, the main function of the aggregate device 10 is to recover the tested concrete discharged from the test container 2, and mix it with the concrete delivered through the overflow return channel 16 and then deliver it to the construction warehouse surface. According to the conditions of the construction site, a pumping device or an aggregate hopper can generally be used as the aggregate device 10.

[0084] In some embodiments, the gate group 3 includes: a drainage gate 31 arranged at the feed port of the drainage channel 11 in the concrete drainage device 1, and the opening and closing of the gate realizes the connection and disconnection of the passage between the fresh concrete discharge channel or discharge point and the concrete drainage device 1, so as to control whether to drain the concrete for detection; a feed gate 32 arranged at the bottom of the drainage discharge port 13 in the concrete drainage device 1, and the opening and closing of the gate realizes the connection and disconnection of the passage between the concrete drainage device 1 and the detection container 2, so as to automatically control the concrete detection drainage. When the amount of concrete discharged into the detection container 2 reaches a certain value, the feed gate 32 is closed to stop feeding; a discharge gate 33 arranged at the bottom of the detection discharge port 24 in the detection container 2, and the opening and closing of the gate realizes the connection and disconnection of the passage between the detection container 2 and the aggregate equipment 3, so as to automatically control the loading and unloading. When the detection container 2 is in the feeding stage, the discharge gate 33 remains closed and the feed gate 32 remains open; when the concrete in the container 2 to be detected reaches the set amount, the discharge gate 33 and the feed valve 32 remain closed, and the detection container 2 is in the static stage; when the liquid level of the concrete in each detection channel of the container 2 to be detected tends to be constant, the detection container 2 enters the discharge stage, the discharge gate 33 is opened, and the feed gate 32 remains closed; the drainage gate 31 is in a normally open state during the detection process, and is only in a closed state when the current batch of concrete does not participate in the detection. Each gate is preferably controlled by a pneumatic gate in conjunction with an electromagnetic valve, and an electric gate and a hydraulic gate can be selected. Optionally, if the concrete viscosity is large or the aggregate particle size is large, a scraper arch breaker 8 can be set on the upper part of the feed gate 32 and the discharge gate 33, and the blades in the scraper arch breaker 8 rotate to avoid the formation of aggregate particle arches and concrete blockage at the concrete drainage device 1 and the discharge port of the detection container 2.

[0085] In some embodiments, the sensing unit 4 is used to collect relevant data in the detection process in real time according to the instructions of the data processing and equipment control terminal 5. The collected data mainly includes the quality of concrete in the detection container 2 and the liquid level of concrete in each detection channel, which are automatically detected in real time by the weight sensor 41 and the liquid level sensor group 42, respectively. The weight sensor 41 preferably adopts a vibrating wire weight sensor, and can also adopt a resistive strain weight sensor or a capacitive weight sensor, which is arranged at the bottom of the detection container 2; the liquid level sensor group 42 is composed of a plurality of liquid level sensors, each of which is arranged directly above a corresponding detection channel in the detection container 2, preferably a laser distance sensor, and can also adopt an ultrasonic distance sensor, an infrared distance sensor or an optical fiber distance sensor. In addition, for the detection container 2 made of transparent material, an image recognition module can also be used to replace the liquid level sensor group 42 to realize the automatic detection of the liquid level in each detection channel. Specifically, the image recognition module obtains the image of each detection channel by adding scale lines on the outer wall of each detection channel in combination with a camera and uses an image recognition algorithm to realize the measurement of the concrete liquid level.

[0086] Furthermore, the sensing unit 4 also includes a temperature sensor added to the inner wall or outer wall of the detection container 2, which is used to detect the temperature of the concrete outlet, so as to provide feedback to guide the mixing station personnel to adjust the concrete outlet temperature; the concrete outlet temperature is related to the peak temperature of the concrete and the subsequent cracking risk. When the concrete outlet temperature is too high, the concrete outlet temperature can be lowered by adding ice and mixing to avoid cracking caused by excessively high concrete temperature; when the concrete outlet temperature is too low, an alarm is issued in time to avoid pouring quality problems due to poor low-temperature fluidity of the concrete.

[0087] Combination Figure 3 The detection principle of the detection container 2 is described as follows:

[0088] The fluidity (plasticity) of fresh concrete is directly related to its yield stress τ0. Under the action of gravity, friction of the side walls (including the side walls of the test container and the surface of the partition) and viscous resistance of motion, the filling height in different connecting channels is different. Specifically: when the pressure P on the concrete is equal to the gravity G and the shear yield resistance F τ0 When the sum of the concrete and the shear yield resistance F is equal, the concrete will stop rising in the channel. τ0It is positively correlated with the yield stress τ0 and the contact area between the concrete and the side wall. It can be seen that the better the concrete fluidity, the smaller the yield stress τ0, and the higher the filling height of the concrete in the channel. The worse the concrete fluidity, the greater the yield stress, and the lower the filling height of the concrete in the channel. Then, the filling height difference of concrete in different channels directly reflects the size of the yield stress τ0, that is, the size of the concrete fluidity (plasticity). The higher the concrete fluidity, the smaller the yield stress τ0 that needs to be overcome by its own weight flow, and the smaller the filling height difference of each liquid surface. Conversely, the greater the filling height difference of each liquid surface. Taking into account the complex influence and randomness brought by the multi-phase nature of concrete itself (aggregate, mortar, air), the quantitative relationship between the concrete fluidity index and the channel liquid surface height difference can be determined by combining theoretical calculations and indoor experiments. It should be pointed out that the purpose of setting multiple detection channels in the embodiment of the present disclosure is: 1) to make the difference of the detection results more significant, that is, to increase the filling height difference; 2) to eliminate the influence of the speed or kinetic energy of the concrete itself on the results.

[0089] Furthermore, the volume of the concrete can be calculated based on the height of the concrete in the detection channel, and the apparent density of the fresh concrete can be inferred in combination with its mass.

[0090] Furthermore, the viscosity and anti-segregation properties of concrete can be evaluated based on the concrete discharge time or discharge rate; the quantitative relationship between the concrete viscosity index and the discharge rate of the test container can be determined by indoor tests;

[0091] Furthermore, the uniformity of fresh concrete is evaluated based on the fluctuation and uniformity of the concrete discharge rate. The smaller the fluctuation of the discharge rate during the discharge process, the smoother the curve of the discharge mass changing with time, indicating that the discharge process is more uniform, that is, the uniformity and workability of the concrete are better; conversely, the more complex and tortuous the curve of the discharge mass changing with time is, the worse the uniformity of the concrete is;

[0092] Furthermore, the gap passability is determined based on whether the concrete can smoothly pass through the detection container 2 and the built-in obstacle steel bars 23 .

[0093] In some embodiments, the data processing and equipment control terminal 5 is responsible for processing various sensor data and automatically controlling the gate; a network port or a 4G module is provided in the data processing and equipment control terminal 5, and the collected measurement data and test results can be uploaded to the cloud platform 6 by wired or wireless means; wherein, the data processing and equipment control terminal 5 calculates the fluidity index I of the concrete according to the liquid level height of the concrete in each detection channel collected by the sensor unit 4 at the initial moment of unloading of the detection container 2 f and the apparent density ρ c0According to the concrete mass data collected by the sensing unit 4 during the unloading process of the detection container 2, the concrete unloading mass - time curve is obtained, and the viscosity index of the concrete is calculated. v and Uniformity Indicator UI c .

[0094] Furthermore, the processing and gate control of various sensors by the data processing and equipment control terminal 5 include: collecting various sensor data at a certain frequency (which can be remotely controlled through the cloud platform 7), including the data of the weight sensor 41 and the liquid level sensor group 42 or the image recognition module; performing operations such as outlier removal and work performance index calculation on the collected measurement data, and uploading the obtained data to the cloud platform 7 through a wired or wireless network for data archiving and push; automatically controlling the gate opening and closing according to a given operation process, and realizing automatic feeding detection and unloading and emptying. Among them, the specific process of the data processing and equipment control terminal 5 calculating the concrete work performance index is:

[0095] The data processing and equipment control terminal 5 determines the fluctuation of the measurement data of the liquid level sensor group 42. When the measurement data of the liquid level sensor group 42 or the image recognition module tends to be stable, that is, no longer changes, it is used as the liquid level height of the concrete in each channel of the detection container 2 at the start of unloading, and the fluidity index I of the concrete is calculated based on the liquid level height. f and the apparent density ρ c0 , the calculation process is as follows:

[0096] According to the liquid height of concrete in each channel measured at the beginning of unloading and the fluidity index I established based on theoretical calculation and indoor test f The quantitative relationship between the liquid level height of each detection channel f() is reversed to obtain the fluidity index of concrete I f :

[0097]

[0098] in, To detect the liquid level of concrete in each channel of the container 2 at the start of unloading, k is the detection channel number, k=1-K, K is the number of detection channels provided in the detection container 2. Further, the slump spread can be selected as a fluidity index to determine f().

[0099] The concrete mass m in the detection container 2 measured at the start of unloading c0 and concrete volume V c0 Calculate the apparent density of concrete ρ c0 :

[0100]

[0101] Among them, Vequ To detect the internal volume of container 2, S k is the cross-sectional area of ​​the kth detection channel, is the upper edge height of the kth detection channel, It is the distance from the liquid surface of concrete in each detection channel to the upper edge of each detection channel.

[0102] Concrete viscosity index I v Related to the average discharge rate, the data processing and equipment control terminal 5 obtains the average discharge rate according to the measured concrete discharge mass-time curve And the viscosity index I established based on theoretical calculations and indoor tests v With average discharge rate The quantitative relationship between g() and the viscosity index of concrete I can be obtained by reverse calculation. v :

[0103]

[0104] It should be noted that when calculating the average unloading rate The unloading start section and unloading end section should be removed to eliminate the influence of the accelerated flow of concrete in the unloading port opening section and the adhesion of the side wall in the unloading end section on the unloading process. The middle section of the unloading process is preferably used as the uniform unloading period, and the average unloading rate is calculated using the data of the uniform unloading period. The uniform unloading period data is the data recorded when the concrete unloading volume reaches 5% to 15% and 85% to 95% of the total volume. v Specifically, V-funnel discharge time, apparent viscosity or Vebe consistency can be selected.

[0105] Furthermore, the average discharge rate of concrete is calculated according to the following formula:

[0106]

[0107] Among them, t1 and m1 are the initial time of the uniform unloading period and the initial unloading mass, respectively. n and m n They are the final time of the uniform unloading period and the final unloading mass;

[0108] Data processing and equipment control terminal 5 calculates the concrete uniformity index UI c The uniform unloading period data is also used. Use any of the following three methods to calculate the uniformity index UI of concrete: c :

[0109] Method 1: Calculate the uniformity index UI of concrete according to the following formula: c :

[0110]

[0111] Among them, m i and m i+1 are the concrete discharge masses at the i-th and i+1-th record values ​​in the uniform discharge period, t i and t i+1 are the time of the i-th and i+1-th record values ​​in the uniform unloading period, respectively; t1 and m1 are the initial time and initial unloading mass of the uniform unloading period, respectively; t n and m n They are the final time of the uniform unloading period and the final unloading mass;

[0112] It should be noted that the advantage of method 1 is that there is no need to perform fitting calculations, and the uniformity index UI can be obtained based on simple calculations c When the fitting calculation capability is available, method 2 or method 3 can also be used for calculation.

[0113] Method 2: Calculation based on the root mean square (RMS) of the residual

[0114] First, the data of the uniform unloading period in the concrete unloading mass-time curve is linearly fitted to obtain the fitting formula:

[0115]

[0116] in, is the estimated value of the concrete discharge mass, t is any moment in the uniform discharge period, a and b are the coefficient and constant term of the linear fit respectively;

[0117] Then, the uniformity index UI of concrete is calculated according to the following formula: c :

[0118]

[0119] in, is the estimated value of the concrete discharge mass at the time corresponding to the i-th record value;

[0120] Method 3: Calculation based on the discriminant coefficient (R square)

[0121] According to the above fitting formula and the following formula, the uniformity index UI of concrete is calculated: c :

[0122]

[0123] in, It is the mean value of the concrete discharge mass during the uniform unloading period.

[0124] Furthermore, according to the batch test results of different types of concrete, this embodiment sets: c >0.85, the concrete uniformity is considered good; when 0.75 <UI c When ≤0.85, the concrete is considered slightly uneven; when 0.60 <UI c When UI is ≤0.75, the concrete uniformity is considered poor; c When ≤0.60, the concrete is considered to be severely non-uniform. For example, for the self-compacting concrete used in a dam construction, the UI measured for concrete with good uniformity is c =0.96, UI measured for concrete with poor uniformity c =0.67. It should be noted that when establishing When the uniformity index UI is removed c <0.85 to eliminate the interference and influence of concrete segregation, blocking and other phenomena on the above relationship.

[0125] The data processing and equipment control terminal 5 calculates the gap passability index δ of the concrete pass When the obstacle occurs, it is judged by whether there is a blockage at the obstacle steel bar:

[0126]

[0127] Among them, whether blockage occurs can be determined by the liquid level of concrete in the feed channel 21. The liquid level threshold is not exceeded When pass =1, indicating that the gap passability of concrete is better; when the concrete liquid level in the feed channel 21 is Exceeding the liquid level threshold When pass =0, indicating that the gap permeability of concrete is poor; the liquid level height threshold It needs to be calculated based on the geometric dimensions of the detection container 2.

[0128] It can be understood that the data processing and equipment control terminal 5 of the embodiment of the present disclosure realizes the following four functions: (1) calculating and evaluating the working performance index of concrete based on the detection data of the sensor unit 4, including but not limited to the fluidity, viscosity, uniformity, anti-segregation, gap permeability, temperature and apparent density of concrete; (2) controlling the opening and closing of the gate group 3 to realize automatic feeding, automatic detection and automatic unloading of concrete working performance detection, thereby realizing unmanned and automated detection; (3) making abnormal alarms for the concrete working performance detection results, and providing feedback to guide the construction personnel to adjust and review the concrete mix ratio to ensure the quality of concrete mixing; (4) storing and sending the detection data and detection results to provide a basis for engineering construction quality assessment and problem tracing.

[0129] In some embodiments, the cloud platform 7 is mainly used to organize and archive the measurement data and test results uploaded by the data processing and equipment control terminal 5. f ,I v 、UI c , c0 and δ pass In case of abnormality, the cloud platform 7 will promptly push the alarm information to the user end, including the mobile terminal 9 carried by the user and the computer in the mixing station. The alarm push types can be divided into two categories: abnormal concrete working performance alarm and abnormal equipment alarm; among which the abnormal working performance includes abnormal fluidity alarm, abnormal viscosity alarm, abnormal uniformity alarm, abnormal apparent density alarm and abnormal gap passability alarm, etc.; abnormal equipment alarm includes abnormal network alarm, abnormal gate control alarm, and concrete blockage alarm. When the equipment is abnormal, the drainage gate 31 is actively closed, and the feed gate 32 and the discharge gate 33 are opened to ensure that no new concrete is introduced into the online monitoring system, and rainwater, flushing water, etc. will not accumulate in the concrete drainage device 1 and the detection container 2, so as to avoid the equipment being completely blocked by concrete and affecting maintenance.

[0130] Furthermore, the online monitoring system of the disclosed embodiment also includes an alarm arranged at the mixing station. When the data processing and equipment control terminal 5 determines that there is an abnormality in the working performance of the concrete, the alarm flashes and beeps to remind the on-site and mixing station personnel to pay attention to the status of the concrete, so as to adapt to the actual conditions where the site is noisy, the light is strong, and it is sometimes inconvenient to view the mobile terminal 9.

[0131] Furthermore, the alarm push of the cloud platform 7 adopts a probabilistic risk mechanism. When any of the above indicators exceeds the design threshold and the risk probability is greater than the design threshold, an alarm reminder will be issued through the mobile terminal 9 and the alarm to remind on-site personnel to make feedback adjustments.

[0132] See also Figure 4The second aspect of the present disclosure provides an online monitoring method for comprehensive concrete working performance based on the above-mentioned online monitoring system, comprising the following steps:

[0133] Step S1, before the mixing station starts to produce concrete, firstly, the sensor unit 4 is set to zero, and the concrete drainage device 1, the detection container 2 and the inner wall of the auxiliary diversion channel are moistened with clean water;

[0134] Step S2: When the mixing station produces concrete, the data acquisition and equipment control terminal 5 is turned on to initialize the opening and closing state of the gate group 3; when detection is required, the drainage gate 31 and the feeding gate 32 are opened, and the discharge gate 33 is closed to enter the feeding process, and part or all of the concrete is guided into the concrete drainage device 1 and the detection container 2 through the drainage channel 11. The concrete flows in the detection container 2 by its own weight and gradually fills each detection channel;

[0135] Step S3: The sensor unit 4 records in real time the mass m of the concrete entering the detection container 2 and the liquid level of the concrete in each detection channel. And transmit to the data acquisition and equipment control terminal 5;

[0136] S4. When the mass m of concrete in the detection container 2 is greater than the mass threshold m0, or the liquid level of concrete in the feed channel 21 reaches the set height threshold, the feed gate 32 is closed and the discharge gate 32 is kept closed. The liquid level of concrete in each detection channel is kept constant for a period of time, such as 40 to 120 seconds, and this is taken as the initial state before discharge. The liquid level of concrete in each detection channel is recorded at this time. and the mass m of concrete in the test container 2 c0 ;

[0137] S5. Open the discharge gate 33 and keep the feed gate 32 closed to start discharging the concrete in the detection container 2. The sensor unit 4 records the concrete mass m(t) in the detection container 2 and the liquid level of the concrete in each detection channel in real time during the discharging process. t represents time; see Figure 5 , which is a monitoring curve of the concrete mass and the distance from the concrete liquid level in each detection channel to the upper edge of the detection container 2 during the process of feeding, standing and unloading of the detection container 2 measured by the sensor unit 4;

[0138] S6, after all the concrete in the container 2 to be tested is discharged, the data acquisition and equipment control terminal 5 records the and m c0 Calculation of concrete fluidity index I f and the apparent density ρ c0According to the m(t) monitoring curve measured by the sensor unit 4 during the unloading process, the viscosity (anti-segregation) index I of the concrete is calculated. v , Uniformity Index UI c , Gap passability index δ pass and other working performance indicators, which are uploaded to the cloud platform 7 as test results together with the measurement data collected by the sensor unit 4;

[0139] S7, the cloud platform 7 performs data archiving, data analysis and alarm push for the data uploaded by the data acquisition and equipment control terminal 5, and the results will be pushed to the user end in real time;

[0140] S8. If the current on-site pouring is not finished, return to step S2 and continue the next segment concrete detection; if the current on-site pouring is finished, close the drainage gate 31, open the feed gate 32 and the discharge gate 33 to ensure that no new concrete is introduced into the online monitoring system, and rainwater, flushing water, etc. will not accumulate in the concrete drainage device 1 and the detection container 2; then use a high-pressure water gun to clean the detection container 2, and wait for the next startup detection.

[0141] In summary, the embodiment of the present disclosure can calculate the yield stress of concrete according to the height of the concrete liquid level in each detection channel of the detection container, and then judge its fluidity; according to the discharge mass-time curve of concrete in the process of discharging from the detection container, the uniformity of concrete discharge can be calculated; when the discharge is basically uniform, the viscosity of concrete can be calculated according to the average discharge rate; when the obstacle steel bar is set in the feeding channel, the gap passability of concrete can be judged by whether blockage occurs during the feeding and unloading process; in addition, according to the volume and mass of concrete in the detection zone 2 at the beginning of unloading, its apparent density can be calculated; thus, the fluidity, uniformity, viscosity, gap passability and apparent density of concrete can be detected through one feeding and unloading process; further, if equipped with a temperature sensor, the current temperature of concrete can also be monitored. The present disclosure is simple and fast and can be combined with the concrete production process to realize real-time detection, rapid evaluation and alarm feedback of the working performance of concrete mixture without interfering with construction, and real-time feedback guides the mixing production of concrete.

[0142] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0143] Although embodiments of the present disclosure have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and alterations may be made to the embodiments without departing from the principles and spirit of the present disclosure, the scope of which is defined by the claims and their equivalents.

Claims

1. An online monitoring system for comprehensive concrete working performance, characterized in that: include: Concrete diversion device, located on the concrete transportation line between the mixing station and the construction warehouse, is used to guide part or all of the concrete for working performance testing; A detection container is located below the concrete drainage device and is used for collecting concrete and detecting working performance; a plurality of detection channels interconnected at the bottom are provided inside the detection container, one of the detection channels is used as a feed channel, and the concrete drawn out from the concrete drainage device enters the detection container through the feed channel; Aggregate equipment, located below the detection container, for recovering the tested concrete discharged from the detection container and transporting it to the construction warehouse surface; A gate group, used to control the on and off of concrete between each passage during the operation of the online monitoring system; A sensing unit, used to measure the mass of concrete in the detection container and the liquid level of concrete in each detection channel in the detection container; A data processing and equipment control terminal is used to control the gate group; calculate a series of indicators of concrete according to the data measured by the sensor unit as the test results of the comprehensive working performance of concrete and make abnormal alarms for the test results of the comprehensive working performance of concrete, as well as store and send the measurement data and test results, wherein the series of indicators include a combination of any multiple indicators of the fluidity, viscosity, uniformity and apparent density of concrete; An equipment bracket, used for installing and arranging the concrete drainage device, the detection container, the gate group, the sensor unit and the data processing and equipment control terminal; The cloud platform communicates with the data processing and device control terminal to archive, analyze and push alarms for the measurement data or test results transmitted by the data processing and device control terminal, and sends the archived data and alarm information to the user end on time or by event according to user needs.

2. The online monitoring system according to claim 1, characterized in that: The concrete drainage device comprises a drainage storage container, a drainage channel, a drainage discharge port, an overflow channel and an overflow return channel; The drainage channel is connected between the fresh concrete unloading channel or unloading point located near the online monitoring system and the upper part of the drainage storage container, and the fresh concrete prepared by the mixing station is transported to the fresh concrete unloading channel or unloading point through a chute or a concrete tanker; The overflow channel is used to discharge the concrete exceeding the volume limit in the drainage storage container and transport it to the aggregate equipment through the overflow return channel. The overflow return channel is also used to transport the concrete that has not participated in the inspection and is transported from the fresh concrete discharge channel or discharge point to the aggregate equipment; The drainage and discharge port is connected between the drainage and storage container and the feeding channel of the detection container.

3. The online monitoring system according to claim 2, characterized in that: The volume limit is 0.8 to 1.2 times the concrete required for a single test of the detection container; the inclination angle α of the overflow channel is 30° to 80°; the upper part of the drainage and discharge port is set in a gradually narrowing form, the inclination angle γ is not less than 50°, and the minimum side length of the cross section of the drainage and discharge port is not less than 5 times the maximum aggregate particle size of the concrete; The drainage storage container is also provided with an isolation screen placed obliquely and connected to the overflow channel to prevent unevenly mixed concrete blocks from entering the drainage discharge port. The aperture of the isolation screen is 3 to 10 times the maximum aggregate particle size of the concrete, and the inclination angle β of the isolation screen is 20° to 50°.

4. The online monitoring system according to claim 1, characterized in that: The interior of the detection container is divided into a plurality of detection channels by a plurality of partitions, the partition spacing is set to be adjustable, the minimum side length of the cross section of any detection channel is not less than 5 times the maximum aggregate particle size of concrete, and the height is not less than 10 times the maximum aggregate particle size of concrete; a detection channel located at the outermost or middle of the detection container is selected as the feed channel, and the cross-sectional area of ​​the feed channel is not less than 1.5 times that of other detection channels.

5. The online monitoring system according to claim 1, characterized in that: A detection discharge port is provided at the bottom of the detection container, and the detection discharge port consists of a gradually narrowing inclined section and a parallel extension section connected to the lower part thereof, the inclination angle θ of the inclined section is 40° to 70°, the cross-section of the detection discharge port is a circle or a regular polygon, the diameter of the parallel extension section is not less than 5 times the maximum aggregate particle size of the concrete; the length of the parallel extension section is not less than 3 times the maximum aggregate particle size of the concrete.

6. The online monitoring system according to claim 1, characterized in that: The gate group includes a drainage gate arranged at the feeding port of the concrete drainage device, a feeding gate arranged at the discharging port of the concrete drainage device for controlling the amount of concrete loaded into the detection container, and a discharge gate arranged at the discharge port of the detection container; when the detection container is in the feeding stage, the discharge gate remains closed and the feeding gate remains open; when the concrete in the detection container reaches a set amount, the discharge gate and the feeding valve are both kept closed, and the detection container is in a static stage; when the liquid level of concrete in each detection channel of the detection container tends to be constant, the detection container enters the discharge stage, the discharge gate is opened, and the feeding gate remains closed; the drainage gate is in a normally open state during the detection process, and is only in a closed state when the current batch of concrete does not participate in the detection.

7. The online monitoring system according to claim 1, characterized in that: The sensing unit includes a weight sensor and a liquid level measurement component; the weight sensor is arranged at the bottom of the detection container; the liquid level measurement component adopts a liquid level sensor group or an image recognition module, the liquid level sensor group is composed of a plurality of liquid level sensors, and each liquid level sensor is respectively arranged just above a corresponding detection channel in the detection container; The image recognition module acquires the image of each detection channel by adding scale lines on the transparent outer side wall of each detection channel in combination with a camera and realizes the measurement of the concrete liquid level by using an image recognition algorithm.

8. The online monitoring system according to claim 7, characterized in that: The sensing unit also includes a temperature sensor provided on the inner wall or the outer wall of the detection container, which is used to monitor the temperature of the concrete outlet.

9. The online monitoring system according to claim 1, characterized in that: The data processing and equipment control terminal calculates the fluidity index I of the concrete according to the liquid level height of the concrete in each detection channel of the detection container at the start of unloading collected by the sensor unit. f and the apparent density ρ c0 According to the concrete mass data collected by the sensing unit in the unloading stage of the detection container, the concrete unloading mass-time curve is obtained, and the viscosity index of the concrete is calculated. v and Uniformity Indicator UI c .

10. The online monitoring system according to claim 9, characterized in that: The data processing and equipment control terminal calculates the fluidity index I of the concrete according to the following formula: f and the apparent density ρ c0 : in, is the liquid level of concrete in each detection channel of the detection container at the beginning of unloading, k is the detection channel number, k=1~K, K is the number of detection channels provided in the detection container, f() is the quantitative relationship between the fluidity index and the liquid level of each detection channel established based on theoretical calculation and indoor test; V equ To detect the internal volume of the container, S k is the cross-sectional area of ​​the kth detection channel, is the upper edge height of the kth detection channel, is the distance from the liquid surface of concrete in each detection channel to the upper edge of each detection channel; The data processing and equipment control terminal calculates the viscosity index I of the concrete according to the following formula: v : in, is the average unloading rate during the uniform unloading period, t1 and m1 are the initial time of the uniform unloading period and the initial unloading mass, respectively, t n and m n are the final time of the uniform unloading period and the final unloading mass, respectively; g() is the quantitative relationship between the viscosity index and the average unloading rate based on theoretical calculations and indoor experiments; The data processing and equipment control terminal uses any of the following three formulas to calculate the uniformity index UI of concrete: c : Among them, m i and m i+1 are the concrete discharge masses at the i-th and i+1-th record values ​​in the uniform discharge period, t i and t i+1 are the time of the i-th and i+1-th recorded values ​​in the uniform unloading period respectively; is the estimated value of the concrete discharge mass at the time corresponding to the i-th record value, which is obtained by linearly fitting the data of the uniform discharge period in the concrete discharge mass-time curve: Calculate the estimate.

11. The online monitoring system according to claim 10, characterized in that: An obstacle steel bar for detecting the gap passability index of concrete is arranged in the feed channel. The data processing and equipment control terminal determines whether the feed channel is blocked according to the liquid level of concrete in the feed channel collected by the sensor unit to calculate the gap passability index. The formula is as follows: Among them, δ pass It is an index of the gap permeability of concrete.

12. The online monitoring system according to claim 1, characterized in that: The online monitoring system also includes an alarm device arranged at the mixing station; The alarm push types of the cloud platform are divided into abnormal concrete working performance alarms and abnormal equipment alarms; the alarm push of the cloud platform adopts a probabilistic risk mechanism. When an abnormality is detected and the risk probability is greater than the design threshold, an alarm reminder is issued through the user terminal and the alarm.

13. An online monitoring method according to any one of claims 1 to 12, characterized in that: The following steps are involved: Step S1, before the mixing station starts to produce concrete, firstly, the sensor unit is set to zero, and the inner wall of the detection container and the connecting pipe thereof are moistened with clean water; Step S2: when the mixing station produces concrete, the data acquisition and equipment control terminal is turned on, the opening and closing state of the gate group is initialized, and part or all of the fresh concrete delivered by the mixing station enters the detection container, and the concrete that does not enter the detection container enters the aggregate equipment; Step S3: Record the mass m of the concrete to be tested entering the detection container and the liquid level of the concrete in each detection channel in real time through the sensor unit. and transmit it to the data acquisition and equipment control terminal; Step S4: When the mass m of the concrete in the detection container is greater than the mass threshold m0, or the liquid level of the concrete in the feed channel reaches the set height threshold, all gates in the gate group are closed and left to stand for a period of time so that the liquid level of the concrete in each detection channel tends to remain unchanged. This is taken as the initial state before unloading, and the liquid level of the concrete in each detection channel at this time is recorded. and the mass of concrete in the test container m c0 ; Step S5: The detection container is unloaded through the gate assembly, and the mass m(t) of the concrete to be tested in the detection container and the liquid level of the concrete in each detection channel are recorded in real time through the sensor unit during the unloading process. t represents time; Step S6: After all the concrete in the detection container is discharged, the data acquisition and equipment control terminal records the and m c0 Calculation of concrete fluidity index I f and the apparent density ρ c0 According to the m(t) measurement curve measured by the sensor unit during the unloading process, the viscosity index I of the concrete is calculated. v and Uniformity Indicator UI c The calculated working performance indicators, including the working performance indicators, are uploaded to the cloud platform as test results together with the measurement data collected by the sensor unit; Step S7, the cloud platform performs data archiving, data analysis and alarm push on the data uploaded by the data acquisition and device control terminal, and the results are pushed to the user end in real time; Step S8: If the current on-site pouring is not finished, return to step S2 and continue the next concrete test; if the current on-site pouring is finished, clean the test container and wait for the next startup test.

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