A method of mass concrete temperature monitoring and conditioning

Abstract

The application discloses a mass concrete temperature monitoring and adjusting method and belongs to the technical field of mass concrete temperature monitoring and adjusting. In the existing mass concrete pouring process, internal temperature gradient is large, interlayer temperature difference is significant, cracks are easily caused, and structural durability is affected due to hydration heat release. Traditional methods rely on single-point threshold, have low spatial resolution, and cannot respond to the temperature change of concrete in real time. The application arranges temperature sensors in layers along cooling water pipes in a concrete pouring bin, and transmits data to an industrial computer in real time. Based on the collected internal temperature, cooling water inlet and outlet water temperature and environmental temperature, a three-dimensional temperature field is reconstructed in combination with thermodynamic parameters. Gradient change abnormal factors and interlayer mutation indexes are calculated to determine the abnormality. According to the determination result, the industrial computer dynamically adjusts the opening degree of the electric valve to realize layered local cooling. The application is suitable for mass concrete pouring, can effectively constrain the interlayer temperature difference, inhibit local high-temperature hot spots, and improve the engineering quality and safety.

Description

Technical Field

[0001] This invention relates to the field of temperature monitoring and regulation technology for large-volume concrete, and in particular to a method for temperature monitoring and regulation of large-volume concrete. Background Technology

[0002] In pumped storage power stations, the spiral casing and tailrace are the key parts that bear the water pressure pulsation during unit operation and are also areas of concentrated vibration. Therefore, the pouring quality requirements for the large volume concrete pouring chamber covering them are extremely high.

[0003] The significant heat of hydration released during the hardening process of concrete pouring can cause a rapid increase in internal temperature (peaking above 70°C), creating a large temperature difference with the external environment. Engineering practice has shown that when this temperature difference exceeds a critical 25°C, the tensile stress induced by the temperature gradient, combined with internal compressive stress, can easily induce plastic shrinkage cracks or, more seriously, penetrating cracks. These cracks weaken the overall structural strength, severely threatening the stability of the unit foundation and the long-term operational life of the power plant. Therefore, precise real-time temperature monitoring is necessary to ensure project quality and safety.

[0004] There are still some problems with temperature control in existing technologies:

[0005] At the monitoring level, the reliance on manual inspections and sparsely deployed sensor networks results in insufficient spatial resolution of the acquired data, making it difficult to accurately reconstruct the temperature field and capture potential high-temperature thermal stress concentration points ("hot spots"), leading to delayed anomaly identification. At the control level, the common practice of using static or semi-static modes with fixed-frequency water pumps and manual valves to adjust the cooling water flow rate cannot respond in real time to the complex dynamic temperature changes inside the concrete pouring chamber, often leading to passive situations of "overcooling" (causing additional shrinkage) or "insufficient temperature control" (exacerbating the risk of cracking). Summary of the Invention

[0006] The purpose of this invention is to provide a method for monitoring and regulating the temperature of large-volume concrete to solve the problems existing in the prior art.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A method for monitoring and regulating the temperature of large-volume concrete includes the following steps:

[0009] S1. In the concrete pouring chamber where temperature monitoring and regulation are required, temperature sensors are laid out in layers along the cooling water pipes, and the measurement data of each temperature sensor is transmitted to the industrial control computer in real time.

[0010] S2. The industrial control computer reconstructs the three-dimensional temperature field of the concrete pouring silo based on the real-time collected internal temperature of the concrete pouring silo, the inlet and outlet water temperatures of the cooling water pipes, and the ambient temperature, combined with the thermodynamic parameters and boundary conditions of the concrete pouring silo.

[0011] S3. Based on the three-dimensional temperature field of the concrete pouring silo, calculate the gradient change anomaly factor and the interlayer mutation index, and make anomaly judgment.

[0012] S4. Based on the judgment result of S3 and the real-time monitoring data, the industrial control computer controls the opening of the electric regulating valves of the cooling water pipelines of each layer to achieve dynamic adjustment of layers and local areas.

[0013] Preferably, the temperature sensor in S1 is a PT100 platinum resistance temperature sensor; each concrete pouring slab is equipped with a temperature monitoring instrument, which communicates with the industrial control computer in real time via an RS485 bus; a temperature sensor is arranged at the inlet and outlet of the cooling water pipe of each concrete pouring slab; each concrete pouring slab is divided into several layers according to the pouring layer height, with a vertical spacing of 1 to 2 meters, and temperature sensors are arranged along the cooling water pipe in each layer.

[0014] Preferably, S2 specifically includes:

[0015] S21. Data Fusion: The industrial control computer integrates the internal temperature of the concrete pouring sump, the inlet and outlet water temperatures of the cooling water pipes, and the ambient temperature in real time, and loads the corresponding temperature sensor deployment location information.

[0016] S22. Visualization: The temperature distribution is rendered with color gradients in the 3D structure diagram, and the real-time monitored data combined with historical data trends are displayed on the monitoring interface.

[0017] S23. Construct unsteady-state heat conduction equations and reconstruct the three-dimensional temperature field of the concrete pouring chamber:

[0018] Assume the volume of the concrete pouring chamber is:

[0019] dV = dx·dy·dz;

[0020] In the formula, dx, dy, and dz represent the length, width, and height of the spatial region, respectively.

[0021] The rate of energy change within a infinitesimal element is:

[0022] ;

[0023] In the formula, For concrete density, For specific heat capacity, , , Represents the heat flux density in the x, y, and z directions. The hydration heat generation rate is represented by T, which is the three-dimensional temperature field of the concrete pouring chamber. It is affected by the internal temperature of the concrete pouring chamber, the inlet and outlet water temperatures of the cooling water pipes, and the ambient temperature. The internal temperature of the concrete pouring chamber is used as the internal measurement point data of the temperature field, and the inlet and outlet water temperatures of the cooling water pipes and the ambient temperature are used as boundary conditions or initial conditions to solve the heat conduction equation.

[0024] Combining Fourier's law of heat conduction, thermal diffusivity is introduced. Let k be the thermal conductivity, and the temperature change equation is:

[0025] .

[0026] Preferably, the gradient change anomaly factor in S3 is calculated according to the following formula:

[0027] ;

[0028] In the formula, Δt is the time window. This refers to the temperature values ​​before and after at the same measuring point within a region based on the three-dimensional temperature field of the concrete pouring chamber. and These represent the average temperature change rates at the right and left ends of the current window, respectively. The weights are preset for the instantaneous temperature change rate. This represents the current rate of temperature change; β is the weighting of temperature fluctuations. This represents the temperature standard deviation.

[0029] Preferably, the interlayer abrupt change index in S3 is calculated according to the following formula:

[0030] ;

[0031] In the formula, Represents vertical coordinates, Lower and upper limits of points This refers to the temperature values ​​of the vertical cross-section within the region based on the three-dimensional temperature field of the concrete pouring chamber. The second derivative of temperature is represented by ΔZ, where ΔZ represents the vertical distance between the measuring points on different levels. , This indicates the volumetric heat capacity of concrete. Indicates the current rate of temperature change. Indicates the maximum temperature rise rate, and the upper and lower limits of integration. The corresponding height of the two measuring points being compared is μ, which represents the threshold factor. When the instantaneous temperature difference between two adjacent layers is greater than 10℃, μ = 1; otherwise, it is 0.

[0032] Preferably, the S3 anomaly determination specifically includes:

[0033] The temperature rise ratio of the sliding window at the measuring point inside the concrete pouring chamber is calculated in real time and continuously monitored every two hours.

[0034] When the temperature of adjacent measuring points exceeds the preset safety threshold and the gradient change abnormal factor exceeds the preset threshold at the same time, it is determined to be an abnormal release of hydration heat and emergency cooling is triggered.

[0035] When the interlayer mutation index exceeds the preset threshold, it is determined that the interlayer cooling rate is abnormal and stratified control is triggered.

[0036] Scan all measuring points. For measuring points where the temperature difference with the outside temperature exceeds 25°C, they are identified as local high-temperature hotspots and emergency cooling is triggered.

[0037] Preferably, the adjacent measuring points are on the same vertical cross section or are measuring points with a spacing of no more than 1.5m.

[0038] Preferably, the real-time control in S4 includes:

[0039] Basic feedback control and exception-driven control;

[0040] The basic feedback control uses the real-time temperature difference of the concrete pouring chamber and the temperature difference between the inlet and outlet of the cooling water as inputs, and adjusts the valve opening according to preset rules. The initial valve opening is 50%, and the valve opening increases by 10% for every 5°C increase in the temperature difference between the inlet and outlet water.

[0041] Preferably, the abnormal drive control includes:

[0042] ① Response to abnormal heat of hydration release: When an abnormal heat of hydration release is detected, increase the total cooling water flow by 20% and activate the backup cooling pipeline;

[0043] ② Interlayer temperature difference abnormal response: When the interlayer cooling rate is determined to be abnormal, the flow rate of the cooling pipes in the upper layer with higher temperature is increased by 15%, and the flow rate of the cooling pipes in the lower layer with lower temperature is reduced by 10%.

[0044] ③ Local high temperature hot spot suppression: When a local high temperature hot spot is identified, the valve opening is increased by 30% in the hot spot zone.

[0045] The present invention discloses a method for monitoring and regulating the temperature of large-volume concrete, which has the following beneficial effects.

[0046] By communicating with a hierarchical distributed high-density temperature sensor and an industrial control computer, and combining this with the heat transfer of the concrete pouring chamber, the reconstruction and visualization of the three-dimensional temperature field inside the concrete pouring chamber were realized. The spatial resolution was significantly improved compared with traditional methods, laying a data foundation for precise temperature control.

[0047] The "gradient change anomaly factor" and "interlayer mutation index" were defined as core criteria, and a multi-level linkage early warning model based on three-dimensional temperature field gradient calculation was constructed. This model breaks through the limitations of traditional single-point threshold alarms, effectively identifying the risks of abnormally accelerated hydration heat release and uneven interlayer cooling, and realizing the transformation from passive response to proactive prediction.

[0048] It effectively constrains interlayer temperature differences and can quickly suppress local high-temperature hot spots, significantly reducing the risk of cracks caused by temperature stress during concrete pouring and improving the durability and safety of engineering structures.

[0049] It is suitable for scenarios such as large-volume concrete pouring silos in hydraulic engineering. By dynamically adjusting the cooling water flow rate in layers, it optimizes resource utilization and improves construction efficiency and automation level. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of device connections in the embodiment.

[0051] Figure 2 This is a schematic diagram showing the arrangement of the concrete pouring chamber and the unit's tailwater pipe and volute in the embodiment.

[0052] Figure 3 This is a distribution diagram of the temperature sensors in the fourth compartment.

[0053] Figure 4 This is a distribution diagram of the temperature sensors in the fifth compartment.

[0054] Figure 5 This is a distribution diagram of temperature sensors in the seventh compartment.

[0055] Figure 6 This is a distribution diagram of temperature sensors in the ninth warehouse.

[0056] Figure 7 This is a distribution diagram of temperature sensors in the tenth warehouse.

[0057] Figure 8 This is the real-time monitoring interface for the fourth warehouse.

[0058] Figure 9 This is the main monitoring interface.

[0059] Figure 10 This is a flowchart of a method for monitoring and regulating the temperature of large-volume concrete.

[0060] In the diagram: 1. Constant temperature water tank; 2. Water pump; 3. Electric regulating valve; 4. Electromagnetic flow meter; 5. Temperature monitoring instrument; 6. Temperature sensor; 7. Industrial control computer; 8. Concrete pouring silo; 804. Fourth silo; 805. Fifth silo; 807. Seventh silo; 809. Ninth silo; 8010. Tenth silo; 9. Cooling water pipe; 10. Water tank temperature control module; 11. Wireless transmission module; 12. Host computer; 13. Unit tailwater pipe; 14. Volute. Detailed Implementation

[0061] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0062] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0063] As disclosed in the background section, there are still some problems with temperature monitoring and regulation of large-volume concrete:

[0064] At the monitoring level, the reliance on manual inspections and sparsely deployed sensor networks results in insufficient spatial resolution of the acquired data, making it difficult to accurately reconstruct the temperature field and capture potential high-temperature thermal stress concentration points ("hot spots"), leading to delayed anomaly identification. At the control level, the common practice of using static or semi-static modes with fixed-frequency water pumps and manual valves to adjust the cooling water flow rate cannot respond in real time to the complex dynamic temperature changes inside the concrete pouring chamber, often leading to passive situations of "overcooling" (causing additional shrinkage) or "insufficient temperature control" (exacerbating the risk of cracking).

[0065] To improve the above problems, such as Figure 10 As shown, this invention proposes a method for monitoring and regulating the temperature of large-volume concrete, comprising the following steps:

[0066] S1. In the concrete pouring chamber where temperature monitoring and regulation are required, temperature sensors are laid out in layers along the cooling water pipes, and the measurement data of each temperature sensor is transmitted to the industrial control computer in real time.

[0067] S2. The industrial control computer reconstructs the three-dimensional temperature field of the concrete pouring silo based on the real-time collected internal temperature of the concrete pouring silo, the inlet and outlet water temperatures of the cooling water pipes, and the ambient temperature, combined with the thermodynamic parameters and boundary conditions of the concrete pouring silo.

[0068] S3. Based on the three-dimensional temperature field of the concrete pouring silo, calculate the gradient change anomaly factor and the interlayer mutation index, and make anomaly judgment.

[0069] S4. Based on the judgment result of S3 and the real-time monitoring data, the industrial control computer controls the opening of the electric regulating valves of the cooling water pipelines of each layer to achieve dynamic adjustment of layers and local areas.

[0070] The technical solution provided by this invention uses a hierarchical distributed high-density temperature sensor network to communicate with an industrial control computer, combined with the heat transfer of the concrete pouring silo, to realize the real-time dynamic reconstruction and visualization of the three-dimensional temperature field inside the concrete pouring silo. The spatial resolution is significantly improved compared with traditional methods, laying a data foundation for precise temperature control.

[0071] The "gradient change anomaly factor" and "interlayer mutation index" were defined as core criteria, and a multi-level linkage early warning model based on three-dimensional temperature field gradient calculation was constructed. This model breaks through the limitations of traditional single-point threshold alarms, and can effectively identify the risks of abnormal acceleration of hydration heat release and uneven interlayer cooling, realizing the transformation from passive response to proactive prediction.

[0072] The model effectively constrains the interlayer temperature difference to below 15℃ and can quickly suppress local high-temperature hotspots (≥60℃).

[0073] The above plan will be explained in detail below.

[0074] In one specific embodiment, the device used in this application mainly consists of a sensor unit, an industrial control computer, and various hardware devices. These three components work together to achieve accurate acquisition, processing, and display of temperature data. The human-machine interface is designed using configuration software. Details of the overall hardware configuration for temperature monitoring can be found in Table 1. This table lists the model, specifications, and key performance parameters of each hardware component to ensure the overall reliability, accuracy, and stability of the model, meeting the stringent requirements of temperature monitoring in industrial settings.

[0075] Table 1 Hardware Configuration

[0076]

[0077] The above equipment is as per the appendix Figure 1 To establish a connection, the specific functions are as follows:

[0078] Temperature sensor 6 is responsible for real-time acquisition of temperature signals inside the large-volume concrete pouring chamber 8, the inlet and outlet temperatures of the cooling water pipe 9, and the temperature of the constant-temperature water tank 1, and transmits this data to the temperature monitoring instrument 5. The temperature monitoring instrument 5 uses RS485 bus communication to transmit the temperature data to the industrial control computer, i.e., the industrial control computer 7, in real time. Electromagnetic flow meter 4 collects the cooling water supply of the concrete pouring chamber and transmits it to the industrial control computer 7 in real time. The constant-temperature water tank 1 transmits its water level data to the industrial control computer 7, and the water pump 2 transmits its operating status parameters to the industrial control computer 7 in real time. The constant-temperature water tank 1 is connected to both internal and external cooling water sources, and is equipped with a level gauge and temperature sensor 6.

[0079] It should be noted that the temperature monitoring instrument 5 is mainly used for real-time monitoring and recording of multi-channel temperature data, and can be extended to process parameter detection such as flow rate and liquid level. In this embodiment, the liquid level gauge and electromagnetic flow meter 4 are directly connected to the temperature monitoring instrument 5. The data from the temperature sensor 6, liquid level gauge and electromagnetic flow meter 4 are first transmitted to the temperature monitoring instrument 5, and then transmitted by the temperature monitoring instrument 5 to the industrial control computer 7 via RS485.

[0080] Water pump 2 and electric regulating valve 3, under the control of control commands issued by industrial control computer 7, regulate the cooling water flow rate. In this embodiment, the temperature of constant temperature water tank 1 is maintained within an adjustable range of 15-25℃.

[0081] The industrial control computer 7 is mainly responsible for the following tasks: ① Receiving temperature signals from the concrete pouring sump temperature monitoring instrument 5 and status signals from the water pump 2 and electric regulating valve 3 via the standard RS485 data communication interface, and controlling the relevant equipment by sending commands manually; ② Analyzing, processing and calculating all collected data (including concrete pouring sump temperature, water supply, inlet and outlet temperatures, water tank level / temperature, etc.); ③ The control logic unit generates control commands for the water pump 2, electric regulating valve 3 and water tank temperature control module 10 based on the concrete pouring sump temperature change requirements and the preset control strategy; ④ Displaying parameters such as concrete pouring sump temperature, cooling water supply, and water supply temperature in real time, and collecting, recording, storing and issuing early warnings for the temperature data at the monitoring points, and transmitting the temperature data at the monitoring points to the host computer 12 via the wireless transmission module 11.

[0082] In this implementation, such as Figure 9 As shown, a human-machine interface (HMI) is also provided to offer an intuitive graphical user interface, facilitating parameter setting, status monitoring, and alarm information viewing for operators. It supports data exchange and remote control between the model and external devices or a remote monitoring center, enabling remote monitoring and management functions.

[0083] The above-mentioned equipment will be used for temperature monitoring and adjustment of large-volume concrete according to the following procedure:

[0084] S1. In the concrete pouring chamber where temperature monitoring and regulation are required, temperature sensors are laid out in layers along the cooling water pipes, and the measurement data of each temperature sensor is transmitted to the industrial control computer in real time.

[0085] It should be noted that, in this embodiment, as Figure 2 As shown, there are 10 concrete pouring chambers, numbered from bottom to top as chamber 1 (801) to chamber 10 (8010). Since the tailpipe 13 and volute 14 are the core vibration zones during operation, the quality requirements for the concrete pouring chambers are higher. Therefore, temperature sensors need to be installed along the cooling water pipes in the concrete pouring chambers that directly contact the tailpipe 13 and volute 14, and the measurement data from each temperature sensor is transmitted to the industrial control computer in real time. Specifically, in this embodiment, as shown... Figure 2 As shown, compartments 804, 805, 807, 809, and 8010 directly contact the unit's tailwater pipe 13 and volute 14. Temperature sensors are installed in compartments 804, 805, 807, 809, and 8010 along the cooling water pipe, and the measurement data from each temperature sensor is transmitted to the industrial control computer in real time. No sensors are installed in the concrete pouring compartments not mentioned.

[0086] Preferably, in this embodiment, the temperature sensor is a PT100 platinum resistance temperature sensor; each concrete pouring slab is equipped with a temperature monitoring instrument, which communicates with the industrial control computer in real time via an RS485 bus; a temperature sensor is arranged at the inlet and outlet of the cooling water pipe of each concrete pouring slab; each concrete pouring slab is divided into several layers according to the pouring layer height interval of 1 to 2 m, and a temperature sensor is arranged along the cooling water pipe in each layer.

[0087] The temperature sensor must meet the following requirements:

[0088] ① Range adaptability: The range is -30℃ to 130℃, covering the temperature change range (including extreme peaks) of the entire process from concrete pouring to curing.

[0089] ②Accuracy requirements: Accuracy ±0.5℃, meeting the requirement of GB / T51028-2015 for temperature monitoring error ≤1℃.

[0090] ③ Long-term stability: Platinum resistance materials are resistant to oxidation and corrosion, making them suitable for long-term burial in concrete casting chambers.

[0091] ④ Protection level: IP68 (completely dustproof and can be submerged in water for a long time), adaptable to the humid environment inside the concrete pouring chamber and the impact of vibration operation.

[0092] ⑤ Packaging: Stainless steel shell (diameter Φ4mm, length 30mm), tube end fitting with adhesive heat shrink tube (diameter Φ6mm, to avoid excessive pressure causing head bulging), internal epoxy resin seal to ensure compressive strength ≥20MPa.

[0093] The temperature monitoring instrument must meet the following requirements:

[0094] ①Supports multi-channel synchronous acquisition (1 unit per warehouse, each unit supports a maximum of 32 sensors).

[0095] ② Data sampling frequency: Real-time connection to industrial control computer, updated in seconds.

[0096] ③ Communication interface: RS485 / Ethernet, for real-time data transmission with industrial control computer.

[0097] When installing temperature sensors along the cooling water pipes, the design drawing of the concrete pouring slab should be used as the reference. Each slab should be arranged in layers along the vertical direction according to the actual height, and the arrangement should be based on the principle of uniform spatial distribution.

[0098] When arranging in layers, the vertical arrangement is divided according to the height of the pouring layer (interval of 1m to 2m), and the sensors are evenly arranged in each layer; the horizontal arrangement is coordinated with the cooling water pipes, and the sensors are arranged along the direction of the water pipes, with a horizontal spacing of ≤10m.

[0099] When installing temperature sensors on cooling water pipes, one sensor should be placed near the inlet and outlet of each cooling water pipe in each compartment, installed on the outer wall of the pipe (0.5m from the pipe opening).

[0100] In this embodiment, if the temperature sensor is located in an area with dense reinforcement, the temperature sensor should be kept away from the main reinforcement and at least 0.1m away from the reinforcement to prevent thermal interference.

[0101] Specifically, in this embodiment, the temperature sensor is positioned as follows:

[0102] ①The actual height of the fourth compartment 804 is 2.8m. It is arranged in two layers according to the principle of spacing greater than 1m.

[0103] The specific layout of the temperature measuring points is shown in Table 2. The total length in the X direction is 24.9m, the total width in the Y direction is 15.75m, and the total height in the Z direction is 2.8m. Figure 2 The lower left corner of the concrete pouring silo is the reference origin. The schematic diagram of the measuring point layout is shown below. Figure 3 As shown, the measuring points are arranged in two layers. The green measuring points in the figure represent the first layer, and the dark green measuring points represent the second layer.

[0104] Table 2. Schematic diagram of temperature measurement point coordinates

[0105]

[0106] ②The actual height of the fifth compartment 805 is 3.6m. According to the principle of arranging at intervals greater than 1m, it should be arranged in three layers.

[0107] The specific layout of the temperature measuring points is shown in Table 3. The total length in the X direction is 27m, the total width in the Y direction is 15.75m, and the total height in the Z direction is 3.6m. Figure 2 The lower left corner of the concrete pouring silo is the reference origin. The schematic diagram of the measuring point layout is shown below. Figure 4 As shown, the measuring points are arranged in three layers. The green measuring points are the first layer, the dark green measuring points are the second layer, and the black measuring points are the third layer.

[0108] Table 3. Schematic diagram of temperature measuring point coordinates

[0109]

[0110]

[0111] ③The actual height of the seventh warehouse 807 is 2.75m. According to the principle of arranging at intervals greater than 1m, it should be arranged in two layers.

[0112] The specific layout of the temperature measuring points is shown in Table 4. The total length in the X direction is 15.75m, the total width in the Y direction is 15.2m, and the total height in the Z direction is 3.2m. Figure 2 The lower left corner of the concrete pouring silo is the reference origin. The schematic diagram of the measuring point layout is shown below. Figure 5 As shown, based on the design drawing, the measuring points are arranged in two layers. The green measuring points in the figure represent the first layer, and the dark green measuring points represent the second layer.

[0113] Table 4. Schematic diagram of temperature measuring point coordinates

[0114]

[0115] ④ The actual height of Warehouse 809 in the ninth warehouse is 2m. According to the principle of arranging with an interval of more than 1m, it should be arranged in two layers.

[0116] The specific layout of the temperature measuring points is shown in Table 5. The total length in the X direction is 15.75m, the total width in the Y direction is 15.2m, and the total height in the Z direction is 2m. Figure 2 The lower left corner of the concrete pouring silo is the reference origin. The schematic diagram of the measuring point layout is shown below. Figure 6 As shown, the measuring points are arranged in two layers. The green measuring points in the figure represent the first layer, and the dark green measuring points represent the second layer.

[0117] Table 5. Schematic diagram of temperature measurement point coordinates

[0118]

[0119] ⑤ The actual height of the tenth warehouse 8010 is 2.75m. According to the principle of arranging at intervals greater than 1m, it should be arranged in two layers.

[0120] The specific layout of temperature measuring points is shown in Table 6. The three-dimensional structure of the tenth compartment (8010) is similar to that of the ninth compartment (809). Referring to the layout of the ninth compartment (809), the total length in the X direction is 15.75m, the total width in the Y direction is 15.2m, and the total height in the Z direction is 2.75m. Figure 2 The lower left corner of the concrete pouring silo is the reference origin. The schematic diagram of the measuring point layout is shown below. Figure 7 As shown, the measuring points are arranged in two layers. The green measuring points in the figure represent the first layer, and the dark green measuring points represent the second layer.

[0121] Table 6. Schematic diagram of temperature measurement point coordinates

[0122]

[0123] S2. The industrial control computer reconstructs the three-dimensional temperature field of the concrete pouring silo based on the real-time collected internal temperature of the concrete pouring silo, the inlet and outlet water temperatures of the cooling water pipes, and the ambient temperature, combined with the thermodynamic parameters and boundary conditions of the concrete pouring silo.

[0124] Preferably, in this embodiment, S2 specifically includes:

[0125] S21. Data Fusion: The industrial control computer integrates the internal temperature of the concrete pouring sump, the inlet and outlet water temperatures of the cooling water pipes, and the ambient temperature in real time, and loads the corresponding temperature sensor deployment location information.

[0126] S22. Visualization: The temperature distribution is rendered with color gradients in the 3D structure diagram, and the real-time monitored data combined with historical data trends are displayed on the monitoring interface.

[0127] S23. Construct unsteady-state heat conduction equations and reconstruct the three-dimensional temperature field of the concrete pouring chamber:

[0128] Assume the volume of the concrete pouring chamber is:

[0129] dV = dx·dy·dz;

[0130] In the formula, dx, dy, and dz represent the length, width, and height of the spatial region, respectively.

[0131] The rate of energy change within a infinitesimal element is:

[0132] ;

[0133] In the formula, For concrete density, For specific heat capacity, , , Represents the heat flux density in the x, y, and z directions. The hydration heat generation rate is represented by T. It should be noted that in this embodiment, T is the three-dimensional temperature field of the concrete pouring chamber, which is affected by the internal temperature of the concrete pouring chamber, the inlet and outlet water temperatures of the cooling water pipes, and the ambient temperature. The internal temperature of the concrete pouring chamber is used as the internal measurement point data of the temperature field, and the inlet and outlet water temperatures of the cooling water pipes and the ambient temperature are used as boundary conditions or initial conditions to solve the heat conduction equation.

[0134] Combining Fourier's law of heat conduction, thermal diffusivity is introduced. Where k is the thermal conductivity, and the temperature change is:

[0135] ;

[0136] Specifically in this embodiment, (1) data fusion: the industrial control computer integrates the internal temperature of the concrete pouring silo, the inlet and outlet water temperature of the cooling water pipe, and the ambient temperature in real time, and loads the corresponding temperature sensor deployment location information to realize real-time monitoring of the temperature in all directions inside the concrete pouring silo.

[0137] (2) Visual presentation, such as Figure 8 As shown in the central area, the temperature distribution is rendered using color gradients in the 3D structure diagram of the interface (temperatures greater than 60℃ are marked in red, temperatures greater than 20℃ and less than 60℃ are marked in green (represented by light green and dark green respectively depending on the different vertical spatial positions), and temperatures less than 20℃ are marked in blue or other colors that are highly distinguishable from red and green). Figure 8 (No temperature below 20℃ was observed in the monitoring). The data was combined with historical data trends and calculated using the heat conduction equation, which was then displayed on the monitoring interface.

[0138] (3) Based on the finite element algorithm, combined with the thermodynamic parameters and boundary conditions of the concrete pouring silo, an unsteady heat conduction equation is constructed, and the temperature field is subsequently reconstructed:

[0139] Assume the volume of the concrete pouring chamber is:

[0140] dV = dx·dy·dz;

[0141] In the formula, dx, dy, and dz represent the length, width, and height of the spatial region, respectively.

[0142] The rate of energy change within a infinitesimal element is:

[0143] ;

[0144] In the formula, Concrete density (kg / m³) 3c represents the specific heat capacity (J / (kg⋅K)), T represents the three-dimensional temperature field of the concrete pouring chamber, which is affected by the internal temperature of the concrete pouring chamber, the inlet and outlet water temperatures of the cooling water pipes, and the ambient temperature. The internal temperature of the concrete pouring chamber is used as internal measurement point data for the temperature field, while the inlet and outlet water temperatures of the cooling water pipes and the ambient temperature are used as boundary conditions or initial conditions to solve the heat conduction equation (K). x q y q z Represents the heat flux density (W / m³) in the x, y, z directions. 2 ), Q gen Indicates the heat of hydration generation rate (W / m 3 );

[0145] According to Fourier's law of heat conduction:

[0146] ;

[0147] In the formula, k is the thermal conductivity (W / (m·K));

[0148] Then the net heat transfer in the x-direction is:

[0149] ;

[0150] Similarly, the net heat in the y and z directions can be obtained; the rate of energy change on the left side can be calculated: ;

[0151] Right-side internal heat source item:

[0152] Q gen dV=Q gen dxdydz;

[0153] Substituting into the law of conservation of energy:

[0154] ;

[0155] get:

[0156] ;

[0157] Introducing thermal diffusivity (m) 2 / s) Simplified to:

[0158] .

[0159] S3. Based on the three-dimensional temperature field of the concrete pouring silo, calculate the gradient change anomaly factor and the interlayer mutation index, and make anomaly judgment.

[0160] Preferably, in this embodiment, the gradient change anomaly factor in S3 is calculated according to the following formula:

[0161] ;

[0162] In the formula, Δt is the time window. This refers to the temperature values ​​before and after at the same measuring point within a region based on the three-dimensional temperature field of the concrete pouring chamber. and These represent the average temperature change rates at the right and left ends of the current window, respectively. The weights are preset for the instantaneous temperature change rate. This represents the current rate of temperature change; β is the weighting of temperature fluctuations. This represents the standard deviation of temperature.

[0163] It should be noted that concrete pouring troughs release a significant amount of heat of hydration during the setting and hardening process. If this heat accumulates excessively or the release rate is abnormal, it can lead to excessive temperature stress within the concrete trough, causing cracks and severely impacting the safety and durability of the engineering structure. To effectively warn and control the potential risks caused by the heat of hydration in concrete pouring troughs, a time-series gradient anomaly factor is introduced as a criterion. By real-time monitoring and analysis of the temperature change rate within the concrete trough, early identification of abnormal heat of hydration release is achieved. The calculation process is as follows:

[0164] (1) Data source: Use data dictionary to associate and obtain temperature sensor data embedded in the concrete pouring chamber in real time, define high-efficiency memory variables to cache temperature data in different time periods, and ensure the real-time performance and accuracy of the calculation.

[0165] Specifically, in this embodiment, real-time data exchange between the configuration network and field hardware devices is achieved through I / O variables. Specifically, each temperature variable defined in the data dictionary is directly associated with a specific physical sensor channel. This embodiment uses the Modicon series, with the variable register set to 40001 (corresponding to channel 0 of the temperature monitoring instrument), and the data type defined as FLOAT (floating-point number) to accurately receive temperature values ​​with decimal places. The sensor converts the physical temperature signal inside the concrete pouring chamber into an electrical signal, which is acquired through the analog input module and transmitted to the host computer via the RS-485 bus. When defining variables, an engineering conversion (linear conversion: minimum raw value 0 corresponds to 0℃, maximum raw value 1000 corresponds to 100℃) needs to be set according to the sensor range (e.g., 0-100℃) to ensure that the acquired raw signal values ​​can be accurately converted into actual engineering values.

[0166] (2) Calculation window division: Each two-hour period is a calculation window (e.g., 12:00–14:00 is window W1, 14:00–16:00 is window W2) to ensure continuous reading of the latest data;

[0167] (3) Within each calculation window, calculate the temperature difference between the two ends of the window to quantify the temperature rise during that time period and calculate the temperature rise value of adjacent windows:

[0168] (4) Calculation of gradient change anomaly factor:

[0169] ;

[0170] In the formula, Δt is the time window. This refers to the temperature values ​​before and after at the same measuring point within a region based on the three-dimensional temperature field of the concrete pouring chamber. and These represent the average temperature change rates at the right and left ends of the current window, respectively. The weights are preset for the instantaneous temperature change rate. This represents the current rate of temperature change; β is the weighting of temperature fluctuations. For temperature standard deviation, The value of β ranges from 0 to 1. The core of this strategy lies in calculating and continuously monitoring the temperature rise ratio of the sliding window at each measuring point inside the concrete pouring chamber every two hours in real time. To avoid false alarms caused by occasional fluctuations at a single measuring point, a spatial synchronicity criterion is introduced: when adjacent measuring points (usually referring to multiple measuring points in the same cross section or close area) also synchronously show this G... t Only when the level exceeds the limit will it be ultimately determined as an abnormal release of heat of hydration, and the preset response mechanism will be immediately triggered.

[0171] Preferably, in this embodiment, the interlayer mutation index in S3 is calculated according to the following formula:

[0172] ;

[0173] In the formula, Represents vertical coordinates, Lower and upper limits of points This refers to the temperature values ​​of the vertical cross-section within the region based on the three-dimensional temperature field of the concrete pouring chamber. The second derivative of temperature is represented by ΔZ, where ΔZ represents the vertical distance between the measuring points on different levels. , This indicates the volumetric heat capacity of concrete. This represents the current rate of temperature change, max. Indicates the maximum temperature rise rate, and the upper and lower limits of integration. The corresponding height of the two measuring points being compared is μ, which represents the threshold factor. When the instantaneous temperature difference between two adjacent layers is greater than 10℃, μ = 1; otherwise, it is 0.

[0174] It should be noted that during the large-volume pouring of hydraulic concrete, the complex interaction of factors such as heat dissipation, heat release of hydration, and ambient temperature can easily lead to uneven cooling in the vertical direction, resulting in the accumulation of interlayer temperature stress and becoming a key factor inducing interlayer cracks in the concrete pouring section. To effectively avoid such risks, the monitoring model introduces the "interlayer mutation index" as a key monitoring indicator, aiming to assess in real time and quantitatively the difference in cooling rate or temperature rise mismatch of the thick pouring layers in the vertical direction.

[0175] This index reflects the relative difference in temperature change trends between adjacent cast-in-place layers over a short period of time. It is defined as the ratio of the difference in temperature rise between adjacent thick cast-in-place layers in the vertical direction within the same time step to the distance between the two layers (layer thickness). Its calculation process mainly includes the following three key steps:

[0176] (1) Dynamic coupling of data:

[0177] The model dynamically correlates with predefined data variables and temperature monitoring points deployed on-site within the concrete pouring chamber in real time. Each monitoring point corresponds to a temperature sensor, ensuring real-time acquisition of temperature changes at each point. For adjacent vertical monitoring points (e.g., upper layer Z1=1.75m and lower layer Z2=1.25m), the acquired temperature data is cached in memory using dual-channel time-series data streams. This ensures a high degree of synchronization between temperature data in adjacent pouring layers in both time and space dimensions.

[0178] Specifically, in this embodiment, an I / O real-valued variable is precisely defined for each physical temperature measurement point (e.g., upper layer Z1=1.75m and lower layer Z2=1.25m) in the configuration network data dictionary. This one-to-one mapping relationship is achieved by configuring the device address of the variable. For example, the sensor signal of upper layer measurement point Z1 is connected to channel 5 of the inspection instrument, and its variable address is 40005; the variable for lower layer measurement point Z2 is 40006. Each variable has an independently set data acquisition period (30 seconds in this example) to ensure that the configuration network operating system actively reads data from the hardware channel at a stable frequency, thereby achieving independent, real-time, and complete acquisition of temperature changes at each measurement point. To enable comparative analysis, after acquiring the original value of the I / O variable, it is temporarily stored in a specially defined memory variable, forming two parallel time-series data streams. The specific implementation is as follows:

[0179] 1. Variable definition: Define variable names as measurement point Z1 and measurement point Z2 as memory variables for caching.

[0180] 2. Data flow: Using event command language, write a script to trigger every 30 seconds and assign the real-time values ​​of the two I / O variables, Z1 and Z2, to the corresponding memory cache variables.

[0181] 3. Timing Alignment: For subsequent temperature gradient calculation, it is necessary to ensure that the data from the two measurement points are strictly aligned in timestamps. This can be achieved by synchronously assigning a pair of I / O variables to a pair of memory variables in the same event command language script, thereby ensuring that in any acquisition cycle, the measurement points Z1 and Z2 used for calculation represent the temperature values ​​at the same moment, forming a synchronous "dual-channel data stream".

[0182] Furthermore, it maintains a high degree of synchronization in both time and space dimensions: ① Time dimension synchronization: The core of this is the optimization of the data collection strategy and triggering logic. In addition to the aforementioned synchronization assignment script, all data points are stamped with a unified timestamp and recorded in alarms or historical data to ensure that the data is completely aligned on the timeline during subsequent queries and analyses.

[0183] 4. Spatial Dimension Synchronization: In the configuration network screen, the real-time data and historical curves of these two measuring points are bound to the physical location diagram (such as a cross-sectional view of a concrete pouring silo column marked with points Z1 and Z2). Through the animation connection function, the data display points on the screen are made to correspond precisely with the sensor positions in the diagram.

[0184] (2) Precise calculation of the interlayer abrupt change index:

[0185] After acquiring synchronized temperature data, the inter-layer abrupt change index is precisely calculated according to a preset time interval. The calculation formula is as follows:

[0186] ;

[0187] In the formula, Represents vertical coordinates, Lower and upper limits of points This refers to the temperature values ​​of the vertical cross-section within the region based on the three-dimensional temperature field of the concrete pouring chamber. The second derivative of temperature is represented by ΔZ, which represents the vertical distance between the measuring points on different levels. , This indicates the volumetric heat capacity of concrete. This represents the current rate of temperature change, max. Indicates the maximum temperature rise rate, and the upper and lower limits of integration. The corresponding height of the two measuring points being compared is μ, which represents the threshold factor. When the instantaneous temperature difference between two adjacent layers is greater than 10℃, μ=1; otherwise, it is 0, thus avoiding invalid calculations.

[0188] Preferably, in this embodiment, the S3 anomaly determination specifically includes:

[0189] The temperature rise ratio of the sliding window at the measuring point inside the concrete pouring chamber is calculated in real time and continuously monitored every two hours.

[0190] When the temperature of adjacent measuring points exceeds the preset safety threshold and the gradient change abnormal factor exceeds the preset threshold at the same time, it is determined to be an abnormal release of hydration heat and emergency cooling is triggered.

[0191] When the interlayer mutation index exceeds the preset threshold, it is determined that the interlayer cooling rate is abnormal and stratified control is triggered.

[0192] Scan all measuring points. For measuring points where the temperature difference with the outside temperature exceeds 25°C, they are identified as local high-temperature hotspots and emergency cooling is triggered.

[0193] Specifically, in this embodiment, the temperature rise ratio of the sliding window at each measuring point inside the concrete pouring chamber is calculated and continuously monitored every two hours in real time. To avoid false alarms caused by occasional fluctuations at a single measuring point, a spatial synchronization criterion is introduced: when the temperatures of adjacent measuring points (adjacent measuring points are on the same vertical section or the distance between them does not exceed 1.5m) exceed a preset safety threshold, and simultaneously G... t When the preset threshold is exceeded, it is determined to be an abnormal release of heat of hydration and emergency cooling is triggered;

[0194] When J t When the interlayer cooling rate exceeds a preset threshold, it is determined to be abnormal and stratified control is triggered; for example, if a certain J t If the temperature exceeds the threshold and only the temperature at measuring point Z1 drops sharply, while the temperature changes at Z2 and other adjacent layers are normal, it indicates that there is a problem of localized excessively rapid cooling at layer Z1.

[0195] Scan all measuring points. For measuring points where the temperature difference with the outside temperature exceeds 25°C, they are identified as local high-temperature hotspots and emergency cooling is triggered.

[0196] S4. Based on the judgment result of S3 and the real-time monitoring data, the industrial control computer controls the opening of the electric regulating valves of the cooling water pipelines of each layer to achieve dynamic adjustment of layers and local areas.

[0197] Preferably, in this embodiment, the real-time control in S4 includes:

[0198] Basic feedback control and exception-driven control;

[0199] The basic feedback control uses the real-time temperature difference of the concrete pouring chamber and the temperature difference between the inlet and outlet of the cooling water as inputs. It adjusts the valve opening according to preset rules. The initial valve opening is 50%. When the temperature difference between the inlet and outlet water increases by 5°C, the valve opening increases by 10%. It should be noted that (the real-time temperature difference is the temperature difference between the measuring point inside the concrete pouring chamber and the outside temperature, and the outside temperature refers to the data from the ambient temperature sensor).

[0200] Anomaly-driven control includes:

[0201] ① Response to abnormal heat of hydration release: When an abnormal heat of hydration release is detected, increase the total cooling water flow by 20% and activate the backup cooling pipeline;

[0202] ② Interlayer temperature difference abnormal response: When the interlayer cooling rate is determined to be abnormal, the flow rate of the cooling pipes in the upper layer with higher temperature is increased by 15%, and the flow rate of the cooling pipes in the lower layer with lower temperature is reduced by 10%.

[0203] ③ Local high temperature hot spot suppression: When a local high temperature hot spot is identified, the valve opening is increased by 30% in the hot spot zone.

[0204] Specifically, in this embodiment, to achieve precise control of the cooling water flow rate in the concrete pouring silo, this application compares real-time monitoring data with preset anomaly factors and uses the RS485 communication protocol to adjust the opening of the electric regulating valve in real time. This aims to maintain the temperature difference between the inside and outside of the concrete pouring silo within 25°C, the interlayer temperature difference within 15°C, and to respond quickly to abnormal single-point temperature rise rates. To this end, the model adopts a three-level collaborative control architecture to address the complex requirements under different operating conditions.

[0205] (1) Basic feedback control

[0206] Under normal operation, the opening of the electric regulating valve is precisely controlled using the real-time temperature difference of the concrete pouring chamber and the temperature difference between the inlet and outlet water of the cooling water pipe as input parameters, thereby dynamically adjusting the cooling water flow rate. The initial valve opening is set to 50% as the baseline flow rate. When the temperature difference between the inlet and outlet increases by 5°C, the valve opening will automatically increase by 10% to achieve dynamic adjustment of the cooling water flow rate and ensure that the cooling efficiency matches the hydration heat release rate.

[0207] (2) Abnormal drive control

[0208] When an abnormal situation is detected, the abnormality-driven control layer is activated, and control quantities are superimposed in real time based on the judgment result of step S3. Specifically:

[0209] ① Abnormal Response to Heat of Hydration Release: When the heat of hydration release rate index Gt exceeds the threshold, it is considered an abnormal heat of hydration release, indicating abnormally active heat of hydration release. The total cooling water flow will be immediately increased by 20% to quickly remove excess heat, and the backup cooling pipes will be activated to enhance overall cooling capacity and prevent the temperature from rising too quickly. ② Abnormal Response to Inter-Layer Temperature Difference: When the inter-layer temperature difference index... When the temperature exceeds the preset limit, it is determined to be an abnormal interlayer cooling rate, indicating vertical temperature unevenness within the concrete pouring chamber. The flow rate of the corresponding layered pipes is adjusted accordingly; for example, the flow rate of the upper pipes with higher temperatures is increased by 15%, while the flow rate of the lower pipes with relatively lower temperatures is reduced by 10%. Based on the independent layered pipe design, precise vertical temperature control is achieved, effectively suppressing the expansion of interlayer temperature differences.

[0210] ③ Suppression of local high-temperature hotspots

[0211] For measuring points where the temperature difference with the outside temperature exceeds 25°C, they are identified as local high-temperature hot spots. The valve opening of the zone where the local high-temperature hot spot is located is increased by 30% to maximize the cooling intensity of the area, accelerate heat dissipation, and thus effectively suppress local thermal stress concentration and avoid potential structural damage caused by local overheating.

[0212] Application examples

[0213] Taking the pouring of 804 concrete in the fourth compartment below the tailrace pipe 13 of a pumped storage power station as an example, the concrete design grade is C30, and the average daily ambient temperature is 25±3℃. The real-time temperature monitoring interface is as follows: Figure 8 As shown. The surface layer of the pouring chamber is 2.7m high, and the pouring volume is 606.8m³. 3 The temperature sensors are deployed in a distributed, 1m-layer vertical arrangement, with two layers (measuring points at elevations of 0.9m and 2.2m). Horizontally, they cover key areas such as the corners and center of the tailrace pipe, totaling 21 temperature measuring points. Dual constant-temperature water tanks maintain a water temperature of 16±1℃, with cooling water flow dynamically controlled by an electric regulating valve. The real-time temperature monitoring interface is shown below. Figure 8 As shown, the highest internal temperature of 58.3℃ was captured within 24 hours after pouring (located at the corner of the tailpipe), and the monitoring interface is as follows. Figure 8 As shown.

[0214] The alarm window on the right records and displays detailed information on temperature exceedance events and their corresponding recovery information in real time, ensuring comprehensive traceability and management of monitoring data. Within 24 hours of the completion of the concrete pouring, a temperature exceedance event was recorded at monitoring point 13, but the temperature returned to the normal range within 2 hours of the exceedance. The system automatically increased the total flow rate by 20% according to the preset control strategy. This response mechanism significantly reduced the rate of temperature recovery after 2 hours, bringing it back to normal levels, thereby effectively controlling the cumulative effect of hydration heat and ensuring the early performance development of the concrete pouring silo.

[0215] The temperature control effect within 48 hours after pouring is shown in the table below:

[0216] Temperature control effect

[0217]

[0218] Figure 8The control panel on the left integrates control functions for eight water pumps, including start / stop, forward / reverse switching, and frequency setting. Below, the real-time information display shows the instantaneous flow rate of each pipeline monitored by the electromagnetic flowmeter and the current opening degree of the electric valves. Valve opening adjustment is integrated into the equipment control interface. A switching button is located at the top center of the interface, supporting simultaneous monitoring of five concrete pouring silos. The central area includes a schematic diagram of the temperature measurement points in the current concrete pouring silo and warning lights. Normal temperatures are indicated by green, while abnormal temperatures turn red, with different shades of green depending on the vertical spatial location. Below, detailed temperature parameters for each measurement point, unit status, and a 3D structural diagram of the concrete pouring silo are listed. The right side is divided into two parts: the upper part is the alarm information recording area for timely querying of abnormal events; the lower part displays the current real-time temperature curve, facilitating preliminary analysis of temperature trends. Additionally, a quick switching button at the top of the interface allows navigation to the equipment control interface and the historical temperature curve and gradient interface.

[0219] Figure 9 The main monitoring interface integrates a device control unit and a parameter display unit, which can simultaneously display the real-time operating parameters of the corresponding equipment while performing start-stop and opening control operations on actuators such as water pumps and valves.

[0220] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for monitoring and regulating the temperature of large-volume concrete, characterized in that, Includes the following steps: S1. In the concrete pouring chamber where temperature monitoring and regulation are required, temperature sensors are laid out in layers along the cooling water pipes, and the measurement data of each temperature sensor is transmitted to the industrial control computer in real time. S2. The industrial control computer reconstructs the three-dimensional temperature field of the concrete pouring silo based on real-time data collected from the internal temperature of the concrete pouring silo, the inlet and outlet water temperatures of the cooling water pipes, and the ambient temperature, combined with the thermodynamic parameters and boundary conditions of the concrete pouring silo. Specifically, the reconstruction of the three-dimensional temperature field of the concrete pouring silo assumes the volume of the concrete pouring silo is: dV = dx·dy·dz; In the formula, dx, dy, and dz represent the length, width, and height of the spatial region, respectively; The rate of energy change within a infinitesimal element is: ； In the formula, For concrete density, For specific heat capacity, , , Represents the heat flux density in the x, y, and z directions. The hydration heat generation rate is represented by T, which is the three-dimensional temperature field of the concrete pouring chamber. It is affected by the internal temperature of the concrete pouring chamber, the inlet and outlet water temperatures of the cooling water pipes, and the ambient temperature. The internal temperature of the concrete pouring chamber is used as the internal measurement point data of the temperature field, and the inlet and outlet water temperatures of the cooling water pipes and the ambient temperature are used as boundary conditions or initial conditions to solve the heat conduction equation. Combining Fourier's law of heat conduction, thermal diffusivity is introduced. Let k be the thermal conductivity, and the temperature change equation is: ； S3. Based on the three-dimensional temperature field of the concrete pouring silo, calculate the gradient change anomaly factor and the interlayer mutation index, and make anomaly judgment. The gradient change anomaly factor is calculated according to the following formula: ； In the formula, Δt is the time window. This refers to the temperature values ​​before and after at the same measuring point within a region based on the three-dimensional temperature field of the concrete pouring chamber. and These represent the average temperature change rates at the right and left ends of the current window, respectively. The weights are preset for the instantaneous temperature change rate. This represents the current rate of temperature change; β is the weight of temperature fluctuation, and σ T The standard deviation of temperature; The interlayer abruptness index is calculated using the following formula: ; In the formula, Represents vertical coordinates, Lower and upper limits of points This refers to the temperature values ​​of the vertical cross-section within the region based on the three-dimensional temperature field of the concrete pouring chamber. The second derivative of temperature is represented by ∆Z, where ∆Z represents the vertical distance between the measuring points on different levels. This indicates the volumetric heat capacity of concrete. Indicates the maximum temperature rise rate, and the upper and lower limits of integration. The corresponding height of the two measuring points being compared is μ, which represents the threshold factor. When the instantaneous temperature difference between two adjacent layers is greater than 10℃, μ = 1; otherwise, it is 0. S4. Based on the judgment result of S3 and the real-time monitoring data, the industrial control computer controls the opening of the electric regulating valves of the cooling water pipelines of each layer to achieve dynamic adjustment of layers and local areas.

2. The method for monitoring and regulating the temperature of large-volume concrete according to claim 1, characterized in that, The temperature sensor mentioned in S1 is a PT100 platinum resistance temperature sensor; each concrete pouring slab is equipped with a temperature monitoring instrument, which communicates with the industrial control computer in real time via an RS485 bus; a temperature sensor is arranged at the inlet and outlet of the cooling water pipe of each concrete pouring slab; each concrete pouring slab is divided into several layers according to the pouring layer height, with a vertical spacing of 1 to 2 meters, and temperature sensors are arranged along the cooling water pipe in each layer.

3. The method for monitoring and regulating the temperature of large-volume concrete according to claim 1 or 2, characterized in that, S2 specifically also includes: S21. Data Fusion: The industrial control computer integrates the internal temperature of the concrete pouring sump, the inlet and outlet water temperatures of the cooling water pipes, and the ambient temperature in real time, and loads the corresponding temperature sensor deployment location information. S22. Visualization: The temperature distribution is rendered with color gradients in the 3D structure diagram, and the real-time monitored data combined with historical data trends are displayed on the monitoring interface.

4. The method for monitoring and regulating the temperature of large-volume concrete according to claim 1, characterized in that, The S3 anomaly determination specifically includes: The temperature rise ratio of the sliding window at the measuring point inside the concrete pouring chamber is calculated in real time and continuously monitored every two hours. When the temperature of adjacent measuring points exceeds the preset safety threshold and the gradient change abnormal factor exceeds the preset threshold at the same time, it is determined to be an abnormal release of hydration heat and emergency cooling is triggered. When the interlayer mutation index exceeds the preset threshold, it is determined that the interlayer cooling rate is abnormal and stratified control is triggered. Scan all measuring points. For measuring points where the temperature difference with the outside temperature exceeds 25°C, they are identified as local high-temperature hotspots and emergency cooling is triggered.

5. The method for monitoring and regulating the temperature of large-volume concrete according to claim 4, characterized in that, The adjacent measuring points are those on the same vertical section or those spaced no more than 1.5m apart.

6. The method for monitoring and regulating the temperature of large-volume concrete according to claim 4, characterized in that, The real-time control in S4 includes: Basic feedback control and exception-driven control; The basic feedback control uses the real-time temperature difference of the concrete pouring chamber and the temperature difference between the inlet and outlet of the cooling water as inputs, and adjusts the valve opening according to preset rules. The initial valve opening is 50%, and the valve opening increases by 10% for every 5°C increase in the temperature difference between the inlet and outlet water.

7. The method for monitoring and regulating the temperature of large-volume concrete according to claim 6, characterized in that, The abnormality drive control includes: ① Response to abnormal heat of hydration release: When an abnormal heat of hydration release is detected, increase the total cooling water flow by 20% and activate the backup cooling pipeline; ② Interlayer temperature difference abnormal response: When the interlayer cooling rate is determined to be abnormal, the flow rate of the cooling pipes in the upper layer with higher temperature is increased by 15%, and the flow rate of the cooling pipes in the lower layer with lower temperature is reduced by 10%. ③ Local high temperature hot spot suppression: When a local high temperature hot spot is identified, the valve opening is increased by 30% in the hot spot zone.

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