A temperature and humidity coordinated regulation method and system for hydraulic concrete maintenance

Abstract

The application discloses a kind of temperature and humidity synergic control method and system for hydraulic concrete maintenance, it is related to the technical field of hydraulic concrete maintenance, technical scheme is, including obtaining internal temperature, near surface temperature and environmental temperature and humidity, determine internal-surface thermal state, surface moisture evaporation driving state and surface cooling constraint state, according to this respectively determine internal cooling water volume, surface maintenance water volume and target surface maintenance water temperature, when water supplement amount increases and there is cooling constraint, keep water supplement amount and adjust water temperature and supply mode, cooling backwater and supplementary maintenance water are mixed and supplied, and according to the time difference of internal cooling and external maintenance response time sequence is coordinated.The beneficial effects of the present application are: while meeting the surface moisture demand, limit the near surface rapid cooling, coordinate the response time sequence of internal cooling and surface maintenance, and improve the utilization rate of cooling backwater.

Description

Technical Field

[0001] This invention relates to the field of hydraulic concrete curing technology, and in particular to a method and system for coordinated temperature and humidity control for hydraulic concrete curing. Background Technology

[0002] Hydraulic concrete is widely used in hydraulic engineering structures such as dams, sluice gates, spillways, foundation slabs, and sidewalls. These structures are typically large in size, and during the early hydration process, they continuously generate a large amount of heat. This internal heat is not easily dissipated in time, easily leading to a temperature distribution where the internal temperature is high while the near-surface temperature is relatively low. If the internal temperature rise is too high or the temperature difference between the internal and near-surface layers is too large, it can easily generate significant thermal stress, increasing the risk of early cracking.

[0003] Currently, for large-volume hydraulic concrete structures, cooling water pipes are typically pre-embedded internally to carry away some of the heat of hydration. Simultaneously, methods such as spraying, misting, or covering the concrete surface are used to reduce moisture loss. In existing curing processes, internal cooling is mostly regulated based on internal temperature or a preset cooling regime, while surface curing is mostly controlled based on ambient temperature and humidity or a preset spraying cycle. There is a lack of coordinated regulation between the two methods, addressing both the internal and near-surface thermal states and the surface moisture loss.

[0004] In actual maintenance, when the ambient temperature is high, the humidity is low, or the near-surface temperature is high, surface moisture evaporation is enhanced, requiring an increase in the amount of surface maintenance water. However, low-temperature maintenance water or a large instantaneous water supply may cause rapid cooling of the near-surface layer, thereby widening the temperature difference between the interior and the near-surface layer. If the surface water supply is directly reduced to limit near-surface cooling, insufficient humidification may result. Therefore, there is a mutual constraint between the surface humidification requirement and the control of near-surface cooling.

[0005] Furthermore, there is a difference in response speed between internal cooling and surface curing. After adjusting the internal cooling water volume, its effect requires gradual heat exchange through cooling pipes and internal heat conduction within the concrete. In contrast, surface spraying or misting can more quickly affect the near-surface thermal and moisture state, easily leading to a situation where internal cooling has not yet fully responded while the near-surface layer has already cooled significantly. Existing curing methods lack targeted timing coordination to address this response time difference.

[0006] Therefore, how to adjust the internal cooling water volume, surface curing water volume, and surface curing water temperature according to the internal-surface thermal state, surface moisture evaporation requirements, and near-surface cooling state, and coordinate the response sequence of internal cooling and surface curing, is a technical problem that needs to be solved in the early-age curing process of hydraulic concrete. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a method and system for coordinated temperature and humidity control in the curing of hydraulic concrete.

[0008] The technical solution includes the following steps: S1. Obtain the internal temperature, near-surface temperature, and ambient temperature and humidity of the hydraulic concrete; S2. Determine the internal-surface thermal state based on the internal temperature and the near-surface temperature, determine the surface moisture evaporation driving state based on the near-surface temperature and the ambient temperature and humidity, and determine the surface cooling constraint state based on the change in the near-surface temperature. S3. Determine the internal cooling water volume based on the internal-surface thermal state, determine the surface curing water volume based on the surface moisture evaporation driving state, and determine the target surface curing water temperature based on the internal-surface thermal state and the surface cooling constraint state. S4. When the surface curing water volume increases and the surface is under a surface cooling constraint, the increased surface curing water volume is maintained, and the near-surface cooling is limited by adjusting the target surface curing water temperature and the surface curing water supply method. S5. Mix at least a portion of the cooling return water generated by internal cooling with the replenishing curing water, adjust the mixing ratio of the two according to the target surface curing water temperature, and supply water to the surface of the hydraulic concrete according to the surface curing water volume. S6. Determine the internal cooling-external curing coordination time based on the time difference between the internal cooling response and the surface curing response, and limit the reduction of the target surface curing water temperature within the internal cooling-external curing coordination time. S7. Based on the updated internal-surface thermal state, surface moisture evaporation driving state, and surface cooling constraint state, adjust the internal cooling water volume, surface curing water volume, target surface curing water temperature, and the mixing ratio.

[0009] Further, in step S2, determining the internal-surface thermal state includes: determining the internal-surface temperature difference based on the internal temperature and the near-surface temperature, and determining the rate of temperature difference change based on the internal-surface temperature difference corresponding to adjacent sampling periods; comparing the internal-surface temperature difference with a preset first temperature difference threshold and a preset second temperature difference threshold to determine a low temperature difference state, a medium temperature difference state, or a high temperature difference state, wherein the first temperature difference threshold is less than the second temperature difference threshold; when the internal-surface thermal state determined based on the internal-surface temperature difference does not reach the high temperature difference state, and the rate of temperature difference change reaches a preset growth threshold and is continuously maintained for a preset number of sampling periods, the internal-surface thermal state is increased by one level.

[0010] Further, in step S2, the saturated vapor pressure corresponding to the near-surface thermal state of the hydraulic concrete is determined based on the near-surface temperature, and the actual vapor pressure of the environment adjacent to the surface of the hydraulic concrete is determined based on the ambient temperature and humidity; the surface moisture evaporation driving amount is determined based on the difference between the saturated vapor pressure and the actual vapor pressure, and the surface moisture evaporation driving state is determined based on the surface moisture evaporation driving amount.

[0011] Further, in step S2, the internal-to-surface temperature difference is determined based on the internal temperature and the near-surface temperature, the internal-to-surface temperature difference change trend is determined based on the internal-to-surface temperature difference obtained by continuous sampling, and the near-surface temperature decrease rate is determined based on the near-surface temperature obtained by continuous sampling. The surface cooling constraint state is determined based on the near-surface temperature decrease rate and the internal-surface temperature difference change trend; when the near-surface temperature decrease rate reaches a preset cooling rate threshold, or when the internal-surface temperature difference shows an increasing trend, the surface cooling constraint state is entered.

[0012] Further, in step S3, the surface moisture evaporation driving state is divided into multiple levels, and the surface curing water volume within a control cycle is determined according to the level of the surface moisture evaporation driving state; the allowable curing water temperature difference between the surface curing water and the near-surface layer of the hydraulic concrete is determined according to the internal-surface thermal state and the surface cooling constraint state, and the target surface curing water temperature is determined according to the near-surface temperature and the allowable curing water temperature difference.

[0013] Furthermore, in step S4, when the surface moisture evaporation driving state increases and the surface maintenance water volume increases within a control cycle, and the surface is under the surface cooling constraint state, the unit time supply flow rate of the surface maintenance water is limited, and the water supply duration within the control cycle is extended, so as to maintain the surface maintenance water volume corresponding to the increased surface moisture evaporation driving state.

[0014] Further, in step S5, the temperature of the cooling return water and the temperature of the replenishment maintenance water are obtained, the temperature of the target surface maintenance water is limited to an adjustable temperature range formed by the cooling return water temperature and the replenishment maintenance water temperature, and the mixing ratio of the cooling return water and the replenishment maintenance water is determined according to the limited target surface maintenance water temperature; when the available cooling return water is insufficient to meet the cooling return water demand corresponding to the mixing ratio, the replenishment maintenance water is used to supplement the surface maintenance water volume.

[0015] Furthermore, the internal temperature change trend is determined based on the internal temperature obtained from continuous sampling, and the hydration heating stage, temperature peak approach stage, temperature peak cooling stage, or stable curing stage of the hydraulic concrete is determined based on the internal temperature change trend; the control priority between the internal cooling water volume, surface curing water volume, and target surface curing water temperature is adjusted according to the hydration heating stage, temperature peak approach stage, temperature peak cooling stage, or stable curing stage.

[0016] Further, in step S6, the internal cooling response time corresponding to the internal temperature reaching the preset internal response condition after internal cooling adjustment, and the surface curing response time corresponding to the near-surface temperature reaching the preset surface response condition after surface curing adjustment are determined respectively; when the internal cooling response time is greater than the surface curing response time, the internal cooling-external curing coordination time is determined according to the time difference between the two, and the reduction of the target surface curing water temperature is restricted within the internal cooling-external curing coordination time; when the surface moisture evaporation driving state increases within the internal cooling-external curing coordination time, the corresponding surface curing water volume is met by increasing the supply flow rate of surface curing water and / or extending the water supply duration.

[0017] This invention also provides a temperature and humidity coordinated control system for the curing of hydraulic concrete, including a parameter acquisition module, a thermal state determination module, an evaporation drive determination module, a cooling constraint determination module, a coordinated decision-making module, an internal cooling adjustment module, a mixing water temperature adjustment module, a surface curing module, a timing coordination module, and a feedback adjustment module.

[0018] The parameter acquisition module is used to obtain the internal temperature, near-surface temperature, and ambient temperature and humidity of the hydraulic concrete.

[0019] The thermal state determination module is used to determine the internal-surface thermal state based on the internal temperature and the near-surface temperature.

[0020] The evaporation drive determination module is used to determine the surface moisture evaporation drive state based on the near-surface temperature and ambient temperature and humidity.

[0021] The cooling constraint determination module is used to determine the surface cooling constraint state based on the change in the near-surface temperature.

[0022] The collaborative decision-making module is used to determine the internal cooling water volume based on the internal-surface thermal state, determine the surface curing water volume based on the surface moisture evaporation driving state, determine the target surface curing water temperature based on the internal-surface thermal state and the surface cooling constraint state, and maintain the increased surface curing water volume and adjust the target surface curing water temperature and the surface curing water supply method when the surface curing water volume increases and is under the surface cooling constraint state.

[0023] The internal cooling regulation module is used to regulate the supply of cooling water inside the hydraulic concrete according to the internal cooling water volume.

[0024] The mixing and temperature control module is used to mix at least a portion of the cooling return water generated by internal cooling with the replenishment maintenance water, and adjust the mixing ratio of the cooling return water and the replenishment maintenance water according to the temperature of the maintenance water on the target surface.

[0025] The surface curing module is used to supply the mixed surface curing water to the surface of the hydraulic concrete according to the surface curing water volume.

[0026] The timing coordination module is used to determine the internal cooling-external curing coordination time based on the time difference between the internal cooling response and the surface curing response, and to limit the reduction of the target surface curing water temperature within the internal cooling-external curing coordination time.

[0027] The feedback adjustment module is used to adjust the internal cooling water volume, surface curing water volume, target surface curing water temperature, and mixing ratio based on the updated internal-surface thermal state, surface moisture evaporation driving state, and surface cooling constraint state.

[0028] The beneficial effects of the technical solution provided by the embodiments of the present invention are as follows: 1. By determining the internal-surface thermal state, the surface moisture evaporation driving state and the surface cooling constraint state respectively, the internal cooling water volume, the surface curing water volume and the target surface curing water temperature are adjusted according to the corresponding state, avoiding the simple linkage between internal temperature control and surface humidification, which is conducive to improving the pertinence of curing control.

[0029] 2. When surface moisture evaporation increases and the amount of maintenance water needs to be increased, while there is a near-surface cooling constraint, maintain the required surface maintenance water volume, and reduce the rapid cooling of the near-surface caused by large instantaneous water supply by adjusting the maintenance water temperature, limiting the supply flow rate per unit time, and extending the water supply duration. This will meet the humidification needs while reducing the risk of further widening of the temperature difference between the interior and the near-surface.

[0030] 3. By comparing the internal cooling response time and the surface curing response time, the coordination time between internal cooling and external curing is determined. Within the coordination time, the reduction of the target surface curing water temperature is limited. This can reduce the mismatch caused by the rapid cooling of the surface before the internal cooling has fully responded, and make the timing of internal cooling and surface curing more coordinated.

[0031] 4. Mix at least a portion of the cooling return water generated by internal cooling with the replenished maintenance water, and adjust the mixing ratio according to the target surface maintenance water temperature. While meeting the surface maintenance water volume and temperature requirements, utilize the cooling return water to improve the comprehensive utilization of maintenance water. Attached Figure Description

[0032] Figure 1 This is a flowchart of the temperature and humidity coordinated control method of the present invention; Figure 2 This is a schematic diagram of the temperature and humidity coordinated control logic of the present invention; Figure 3 This is a schematic diagram illustrating the hydration temperature stage and the coordination of the internal cooling-external conditioning sequence in this invention. Detailed Implementation

[0033] Example 1 This embodiment provides a method for coordinated temperature and humidity control in the curing of hydraulic concrete. It is applicable to dam sections, gate piers, spillway bottom slabs, spillway sidewalls, and other hydraulic concrete structures with significant structural thickness and obvious hydration heat release processes in their early stages. This embodiment uses a single hydraulic concrete curing area as the control object. When the area of ​​the structure to be cured is large, multiple curing areas can be divided along the structural surface, and temperature and humidity are coordinated and controlled separately in each curing area. (See also...) Figure 1 In this embodiment, the internal cooling water volume, surface curing water volume, and target surface curing water temperature are synergistically adjusted based on the internal-surface thermal state of hydraulic concrete, the surface moisture evaporation driving state, and the surface cooling constraint state.

[0034] Before the hydraulic concrete is poured, an internal cooling circuit is pre-embedded inside the concrete according to the structural dimensions and hydration heat control requirements. The internal cooling circuit includes a cooling pipe installed inside the concrete and a cooling water supply pipe connected to the inlet end of the cooling pipe. The outlet end of the cooling pipe is connected to the cooling return water pipe. A flow regulating device is installed on the cooling water supply pipe to regulate the flow rate of the cooling water. A diversion structure is installed on the cooling return water pipe so that the cooling return water can enter the drainage branch and the surface curing water channel respectively.

[0035] The surface curing water circuit is also connected to the replenishment curing water pipeline. The cooling return water pipeline and the replenishment curing water pipeline are connected to the mixing unit. The mixing unit can be a proportional mixing valve, a mixing tank, or a dual-inlet mixing pipeline with separate flow regulating valves. The cooling return water and the replenishment curing water are mixed by the mixing unit to form surface curing water. The outlet of the mixing unit is connected to a spray pipeline located near the surface of the hydraulic concrete to be cured. Multiple atomizing nozzles are installed on the spray pipeline. By adjusting the supply flow rate of the surface curing water and the water supply duration within a control cycle, the supply mode of the surface curing water within the control cycle is changed, and the amount of surface curing water supplied to the surface of the hydraulic concrete within the control cycle is controlled.

[0036] At least one internal temperature detection point is set inside the hydraulic concrete, preferably in the core area where hydration heat easily accumulates; at least one near-surface temperature detection point is set at a predetermined depth from the surface to be cured. In this embodiment, the near-surface temperature detection point is set at a distance of 50-150 mm from the concrete surface to reduce the instantaneous disturbance to the detection results caused by surface spraying and short-term changes in the external environment, while reflecting the thermal state of the hydraulic concrete near the curing surface; an environmental temperature and humidity detection unit is set in the vicinity of the surface to be cured, avoiding the direct spray area of ​​the atomizing nozzle, to obtain the ambient temperature and humidity of the adjacent air that exchanges heat and moisture with the surface of the hydraulic concrete.

[0037] When multiple internal temperature detection points are set in the same maintenance area, the maximum value among the multiple internal temperature detection values ​​can be selected as the current internal temperature to reflect the unfavorable heat accumulation state inside the area. When multiple near-surface temperature detection points are set in the same maintenance area, the average value can be taken as the current near-surface temperature after removing obviously abnormal detection values. In this embodiment, the maximum internal temperature and the average near-surface temperature are used to determine the subsequent state.

[0038] During the curing process, internal temperature, near-surface temperature, ambient temperature and ambient humidity are continuously acquired according to a preset sampling cycle. A predetermined time interval is maintained between two adjacent sampling cycles. Through continuous sampling, a temperature and humidity state sequence that changes with the hydration process of hydraulic concrete is formed.

[0039] First, determine the internal-to-surface temperature difference based on the current internal temperature and near-surface temperature:

[0040] For the first The internal-to-surface temperature difference corresponding to each sampling period; For the first The internal temperature of the hydraulic concrete was obtained in one sampling cycle; For the first The near-surface temperature of hydraulic concrete was obtained in one sampling period; This is the sampling period number.

[0041] The internal-to-surface temperature difference is used to reflect the current degree of temperature non-uniformity between the interior and near-surface layers of hydraulic concrete. However, the internal-to-surface temperature difference at a single moment cannot distinguish between different states where the temperature difference is widening and converging. Therefore, the rate of temperature change is further determined based on the internal-to-surface temperature differences of adjacent sampling periods.

[0042] For the first The rate of change of internal-surface temperature difference corresponding to each sampling period; For the first The internal-to-surface temperature difference corresponding to each sampling period; For the first The internal-to-surface temperature difference corresponding to each sampling period; The time interval between two adjacent sampling periods; This is the sampling period number.

[0043] The internal-surface thermal state is determined by the internal-surface temperature difference and the rate of temperature change. In this embodiment, the internal-surface thermal state is divided into low temperature difference state, medium temperature difference state and high temperature difference state based on the internal-surface temperature difference, and a first temperature difference threshold, a second temperature difference threshold and a temperature difference growth threshold are preset, wherein the first temperature difference threshold is less than the second temperature difference threshold.

[0044] When the internal-surface temperature difference is lower than the first temperature difference threshold and the rate of temperature change does not reach the temperature difference growth threshold, the current internal-surface thermal state is determined to be a low temperature difference state; when the internal-surface temperature difference is between the first and second temperature difference thresholds, the current internal-surface thermal state is determined to be a medium temperature difference state; when the internal-surface temperature difference is higher than the second temperature difference threshold, the current internal-surface thermal state is determined to be a high temperature difference state.

[0045] To reduce the lag in temperature difference control, when the internal-surface temperature difference has not yet entered the temperature difference range corresponding to a higher state, but the rate of temperature difference change reaches the temperature difference growth threshold and is maintained for a preset number of sampling periods, the current internal-surface thermal state is raised by one level in advance. For example, when the internal-surface temperature difference is still in the low temperature difference range but continues to expand rapidly, it is adjusted in advance according to the medium temperature difference state. When the internal-surface temperature difference is already in the medium temperature difference range and continues to expand rapidly, it is adjusted in advance according to the high temperature difference state.

[0046] Meanwhile, to avoid frequent switching between adjacent levels of internal-surface thermal state, a hysteresis condition is set for state downgrading. When the internal-surface thermal state transitions from a higher level to a lower level, downgrading is only performed after the internal-surface temperature difference has been below the corresponding downgrading threshold for a consecutive preset number of sampling cycles. Furthermore, the corresponding downgrading threshold is lower than the upgrading threshold corresponding to that level, so that the internal-surface thermal state can respond quickly when the risk increases and exit the higher control level after continuous confirmation when the risk decreases.

[0047] The first temperature difference threshold, the second temperature difference threshold, the temperature difference increase threshold, and the corresponding decrease threshold can be determined in advance based on the thickness of the hydraulic concrete structure, mix proportion, constraints, construction season, and the allowable temperature difference in the engineering design, through specimens with the same mix proportion, on-site test chambers, or existing construction data. For example, 8℃ can be used as the first temperature difference threshold and 15℃ as the second temperature difference threshold, but the above values ​​are only one specific implementation method.

[0048] While determining the internal-surface thermal state, the surface moisture evaporation driving state is determined based on the near-surface temperature, ambient temperature, and ambient humidity. In this embodiment, the near-surface temperature is not directly equated with the actual surface temperature of the hydraulic concrete. Instead, the near-surface temperature is used to characterize the thermal state near the curing surface, and the saturated vapor pressure corresponding to the near-surface thermal state is determined accordingly as a parameter characterizing the surface moisture evaporation trend of the hydraulic concrete.

[0049] The saturated vapor pressure corresponding to the near-surface thermal state is determined by the following formula:

[0050] For the first Each sampling period is determined based on the saturated vapor pressure based on the near-surface temperature of the hydraulic concrete. For the first The near-surface temperature of hydraulic concrete was obtained in one sampling period; The sampling period number; This is the natural exponentiation operator.

[0051] In the above formula , and It is an empirically calculated coefficient used to approximately determine the saturated vapor pressure based on Celsius temperature. In the temperature application range of this embodiment, it is used to characterize the vapor saturation state of near-surface temperature changes.

[0052] Determine the actual water vapor pressure in the air near the surface of the hydraulic concrete based on the ambient temperature and humidity:

[0053] For the first The actual water vapor pressure in the air near the surface of the hydraulic concrete during each sampling period; For the first The percentage of relative humidity in the environment obtained in each sampling period; For the first The ambient temperature obtained in each sampling period; The sampling period number; This is the natural exponentiation operator.

[0054] The driving force for surface moisture evaporation is further determined based on the difference between the saturated water vapor pressure and the actual water vapor pressure of the adjacent air:

[0055] For the first The surface moisture evaporation driving force corresponding to each sampling period; For the first Each sampling period is determined based on the saturated vapor pressure based on the near-surface temperature of the hydraulic concrete. For the first The actual water vapor pressure in the air near the surface of the hydraulic concrete during each sampling period; The sampling period number; This is an operator that selects the larger value between the result calculated within the parentheses and zero.

[0056] The greater the surface moisture evaporation driving force, the greater the difference between the water vapor state near the surface of the hydraulic concrete and the surrounding ambient air, and the stronger the tendency of surface moisture to migrate to the surrounding environment. In this embodiment, a first evaporation threshold and a second evaporation threshold are preset. The first evaporation threshold is less than the second evaporation threshold. When the surface moisture evaporation driving force is not higher than the first evaporation threshold, it is determined to be a low evaporation driving state. When the surface moisture evaporation driving force is higher than the first evaporation threshold but not higher than the second evaporation threshold, it is determined to be a medium evaporation driving state. When the surface moisture evaporation driving force is higher than the second evaporation threshold, it is determined to be a high evaporation driving state.

[0057] The surface moisture evaporation drive state is also set with a state maintenance mechanism. When the surface moisture evaporation drive amount reaches the threshold corresponding to a higher level, it is allowed to upgrade in time. When switching from a higher evaporation drive state to a lower evaporation drive state, the downgrade is only executed after the surface moisture evaporation drive amount has been lowered for a consecutive preset number of sampling cycles. This reduces the frequent switching of surface maintenance water volume caused by short-term fluctuations in canyon wind speed, sunshine and environmental humidity.

[0058] The first evaporation threshold, the second evaporation threshold, and the corresponding downgrade threshold can be pre-calibrated using concrete specimens with the same mix proportion or in a field test chamber. The surface water loss state is recorded under different environmental temperature and humidity conditions, and the surface moisture evaporation driving amount corresponding to the appearance of obvious surface water loss trend and the need to increase external humidification intensity is used as the basis for classifying different evaporation driving states.

[0059] The rate of near-surface temperature decrease was further determined based on the near-surface temperature obtained from continuous sampling.

[0060] For the first The rate of near-surface temperature decrease corresponding to each sampling period; For the first Near-surface temperature obtained in each sampling period; For the first Near-surface temperature obtained in each sampling period; The time interval between two adjacent sampling periods; The sampling period number; This is an operator that selects the larger value between the result calculated within the parentheses and zero.

[0061] A preset cooling rate threshold is established. When the near-surface temperature decrease rate reaches this threshold, the system is determined to be in a surface cooling constraint state. Similarly, if the near-surface temperature decrease rate has not yet reached the threshold, but the internal-surface temperature difference continues to widen, the system also enters a surface cooling constraint state. To reduce misjudgments caused by fluctuations in a single detection, the system can be required to maintain the corresponding conditions for a preset number of sampling periods before entering the surface cooling constraint state, and to exit the state after the corresponding conditions disappear for a preset number of sampling periods.

[0062] In this embodiment, different states are used to determine different control quantities. The internal-surface thermal state is used to determine the internal cooling water volume, the surface moisture evaporation driving state is used to determine the surface curing water volume, and the internal-surface thermal state and the surface cooling constraint state are used together to determine the target surface curing water temperature, so that the surface humidification demand and the surface cooling constraint act on the water volume and thermal state of the surface curing water, respectively.

[0063] The internal cooling water volume is regulated by the internal cooling water flow rate, which is determined by the following formula:

[0064] For the first Internal cooling water flow rate corresponding to each sampling period; For the first Each sampling period is based on the internal cooling water volume coefficient determined according to the internal-surface thermal state; This represents the maximum allowable cooling water flow rate for the internal cooling circuit. This is the sampling period number.

[0065] For example, the internal cooling water volume coefficients corresponding to the three internal-surface thermal state levels of low, medium and high can be taken as 0.35, 0.65 and 1.00 respectively. The specific values ​​are calibrated according to the cooling pipe length, pipe diameter, arrangement spacing, cooling water temperature and the allowable cooling rate of the project. Different internal cooling water volume coefficients can be used under different engineering conditions.

[0066] The surface curing water volume is determined independently based on the surface moisture evaporation driving state. In this embodiment, the surface curing water volume is characterized by the total water volume supplied to the curing area within one control cycle.

[0067] For the first The amount of surface curing water corresponding to each control cycle; For the first Each control cycle is determined based on the maintenance water volume coefficient driven by the surface moisture evaporation state; The maximum amount of surface curing water supplied to the corresponding curing area within a control cycle; This is for controlling the cycle number.

[0068] For example, the maintenance water volume coefficients corresponding to the three surface moisture evaporation drive state levels of low, medium and high can be taken as 0.30, 0.60 and 0.90 respectively. The specific values ​​are calibrated according to the maintenance area, nozzle flow rate, spray coverage and on-site evaporation conditions.

[0069] The surface curing water volume within a control cycle can be achieved by the supply flow rate and the duration of the surface curing water supply. For vertical or inclined surfaces such as gate pier facades, dam faces, or spillway sidewalls, intermittent atomized water supply can be used to distribute the determined surface curing water volume within a control cycle, thereby reducing the formation of significant runoff from continuous water film converging along the concrete surface.

[0070] Cooling water is supplied to the internal cooling circuit according to the determined internal cooling water flow rate. After the cooling water flows through the interior of the hydraulic concrete, it absorbs part of the heat of hydration and forms cooling return water with a temperature change. The temperature of the cooling return water is detected before it enters the mixing unit, and the temperature of the replenishing curing water is detected before it enters the mixing unit.

[0071] The allowable temperature difference between the surface curing water and the near-surface layer of the hydraulic concrete is determined by combining the internal-surface thermal state and the surface cooling constraint state. The higher the internal-surface thermal state level, the smaller the allowable temperature difference of the curing water. When entering the surface cooling constraint state, the temperature difference is further reduced based on the allowable temperature difference of the curing water corresponding to the current internal-surface thermal state, so that the surface curing water temperature is closer to the near-surface temperature of the hydraulic concrete.

[0072] The target surface curing water temperature is determined by the following formula:

[0073] For the first The expected target surface curing water temperature corresponding to each sampling cycle; For the first The near-surface temperature of hydraulic concrete was obtained in one sampling period; For the first Each sampling period is determined based on the allowable temperature difference of the curing water, which is based on the internal-surface thermal state and the surface cooling constraint state. This is the sampling period number.

[0074] For example, under low temperature difference conditions, the allowable temperature difference of the maintenance water can be taken as follows: This allows the surface conditioning water to simultaneously perform a certain degree of surface heat dissipation during the humidification process; under medium temperature difference conditions, the allowable temperature difference of the conditioning water can be reduced to [value missing]. Under high temperature difference conditions, the allowable temperature difference of the maintenance water can be further reduced to [value missing]. This makes the surface curing water temperature closer to the near-surface temperature of the hydraulic concrete. The above values ​​are only one specific implementation method of this embodiment.

[0075] When under surface cooling constraint, the temperature difference can be further reduced based on the above-mentioned allowable temperature difference of the curing water. For example, it can be adjusted to 3℃, 2℃ and 1℃ under low temperature difference, medium temperature difference and high temperature difference conditions, respectively. The specific values ​​are calibrated according to the allowable near-surface cooling rate of the project.

[0076] When the surface moisture evaporation driving state increases, causing the surface maintenance water volume to increase within a control cycle, and the current surface cooling constraint state is maintained, the surface maintenance water volume already determined based on the surface moisture evaporation driving state is not reduced. Instead, the increased surface maintenance water volume is maintained, and the near-surface cooling is limited by increasing or maintaining the target surface maintenance water temperature and changing the surface maintenance water supply method.

[0077] The surface curing water volume within one control cycle must meet the following requirements:

[0078] For the first The amount of surface curing water corresponding to each control cycle; The flow rate of surface curing water supplied during the actual water supply period within this control cycle; This is the cumulative value of the duration of each water supply within the control cycle; This is for controlling the cycle number.

[0079] When the surface is under surface cooling constraint, the flow rate of surface curing water supply Limit the amount of water used for surface maintenance. Extend the water supply duration under unchanged conditions When using intermittent water supply, the water replenishment demand determined by the evaporation-driven state can be met by increasing the number of water supply cycles and / or extending the duration of each water supply, while reducing the concentrated cooling of the near-surface layer caused by large instantaneous water supply.

[0080] Since the expected target surface curing water temperature may exceed the temperature range that can be formed by directly mixing the cooling return water and the makeup curing water, the expected target surface curing water temperature is limited to the adjustable range formed by the two water supply temperatures to obtain the actual target surface curing water temperature:

[0081] For the first Each sampling cycle can be determined by the actual target surface curing water temperature formed by the mixture of cooling return water and replenishing curing water; For the first The expected target surface curing water temperature corresponding to each sampling cycle; For the first The cooling return water temperature obtained from each sampling cycle; For the first The temperature of the replenishing maintenance water obtained from each sampling cycle; The sampling period number; This is an operator that selects the smaller value within the parentheses; This is an operator that selects the larger value within the parentheses.

[0082] Both cooling return water and replenishment maintenance water are water, and the mixing time in the mixing unit is relatively short. Therefore, in this embodiment, when determining the mixing ratio of the two water streams, the short-term heat exchange between the mixing process and the external environment is ignored, and it is approximately assumed that the density and specific heat capacity of the two water streams are the same. Thus, the mixing ratio is determined based on the heat balance between the flow rate ratio of the two water streams and the water temperature.

[0083] When the cooling return water temperature differs from the makeup curing water temperature, the mixing ratio of cooling return water in the surface curing water should be determined based on the actual target surface curing water temperature.

[0084] For the first The mixing ratio of cooling return water to the total surface curing water in each sampling cycle; For the first Each sampling cycle can be determined by the actual target surface curing water temperature formed by the mixture of cooling return water and replenishing curing water; For the first The temperature of the replenishing maintenance water obtained from each sampling cycle; For the first The cooling return water temperature obtained from each sampling cycle; This is the sampling period number.

[0085] To ensure continuous water and heat coupling between the internal cooling return water and the surface curing process, a minimum return water ratio is preset. When the cooling return water mixing ratio calculated based on the actual target surface curing water temperature is lower than the minimum return water ratio, the cooling return water mixing ratio is adjusted to the minimum return water ratio, provided that the surface curing water temperature after mixing is still within the allowable water temperature range. This ensures that at least a portion of the cooling return water discharged from the internal cooling circuit participates in the formation of the surface curing water.

[0086] When the cooling return water temperature is the same as the replenishment maintenance water temperature, the cooling return water ratio is no longer determined by the above mixing ratio calculation formula. Instead, cooling return water is supplied to the mixing unit according to the preset return water utilization ratio. The remaining water required for surface maintenance is provided by the replenishment maintenance water. At this time, the mixing of the two water sources will not change the surface maintenance water temperature.

[0087] The mixing unit controls the flow rate of cooling return water and replenishment maintenance water according to a determined mixing ratio, so that the temperature of the surface maintenance water formed by mixing is close to the actual target surface maintenance water temperature. When the available flow rate of cooling return water is insufficient to meet the cooling return water demand flow rate calculated according to the current mixing ratio, priority is given to ensuring the surface maintenance water volume determined according to the current surface moisture evaporation driving state. Cooling return water is used within the existing available flow rate range, and the remaining flow rate is supplemented by replenishment maintenance water.

[0088] After the surface curing water is formed, water is supplied to the surface of the hydraulic concrete according to the current surface moisture evaporation driving state. When the surface is not under surface cooling constraint, the supply flow rate and water supply duration can be adjusted according to the surface curing water volume. When the surface moisture evaporation driving state increases and the surface is under surface cooling constraint, the increased surface curing water volume is maintained. Rapid cooling of the near-surface layer is limited by restricting the supply flow rate per unit time, extending the water supply duration, and increasing or maintaining the target surface curing water temperature.

[0089] After each control cycle is completed, the internal temperature, near-surface temperature, ambient temperature, and ambient humidity are acquired again. The internal-surface thermal state, surface moisture evaporation driving state, and surface cooling constraint state are redefined. The internal cooling water volume is adjusted according to the updated internal-surface thermal state, the surface curing water volume is adjusted according to the updated surface moisture evaporation driving state, and the target surface curing water temperature is adjusted according to the updated internal-surface thermal state and surface cooling constraint state. At the same time, the mixing ratio of cooling return water and replenishment curing water is redefined according to the updated target surface curing water temperature.

[0090] When the internal-surface thermal state level increases, the corresponding internal cooling water volume is increased; when the surface moisture evaporation drive state level increases, the corresponding surface curing water volume is increased; when the near-surface temperature drop rate reaches the preset cooling rate threshold or the internal-surface temperature difference continues to expand and enters the surface cooling constraint state, while maintaining the surface curing water volume determined by the current surface moisture evaporation drive state, the allowable curing water temperature difference is reduced, and the supply flow rate and water supply duration of the surface curing water are adjusted.

[0091] Example 2 This embodiment further addresses the issue of different response speeds between internal cooling and surface curing in large-volume hydraulic concrete. It coordinates the adjustment sequence of internal cooling water flow rate, surface curing water volume, and surface curing water temperature. Furthermore, it divides different hydration temperature stages according to the internal temperature change characteristics during the hydration heat release process of hydraulic concrete, allowing for different temperature and humidity control priorities at different hydration temperature stages.

[0092] During the curing process, the internal temperature, near-surface temperature, and ambient temperature and humidity of the hydraulic concrete are continuously acquired according to a preset sampling cycle. The internal-surface thermal state is determined based on the internal and near-surface temperatures. The surface moisture evaporation driving state is determined based on the near-surface temperature, ambient temperature, and ambient humidity. The surface cooling constraint state is determined based on the continuous change of the near-surface temperature. The internal-surface thermal state is used to determine the internal cooling water volume, the surface moisture evaporation driving state is used to determine the surface curing water volume, and the internal-surface thermal state and the surface cooling constraint state are used together to determine the target surface curing water temperature.

[0093] After the large-volume concrete of the hydraulic structure is poured, as the cement continues to hydrate, the internal temperature usually goes through a process of significant increase, approaching the temperature peak, decreasing after the temperature peak, and gradually stabilizing. According to the continuous change characteristics of the internal temperature, this embodiment divides the curing process into the hydration heating stage, the temperature peak approach stage, the temperature peak cooling stage, and the stable curing stage. Each stage is switched in the above order. Once the hydration temperature stage is switched to the next stage, it will not return to the previous stage due to short-term reverse fluctuations in the internal temperature, so as to avoid repeated switching of the hydration temperature stage caused by changes in ambient temperature between day and night, cooling water adjustment, or detection disturbances.

[0094] The rate of change of internal temperature is determined based on the internal temperature obtained from two adjacent sampling periods:

[0095] For the first The rate of internal temperature change corresponding to each sampling period; For the first The internal temperature of the hydraulic concrete was obtained in one sampling cycle; For the first The internal temperature of the hydraulic concrete was obtained in one sampling cycle; The time interval between two adjacent sampling periods; This is the sampling period number.

[0096] When the hydraulic concrete has been poured but other stages have not yet been confirmed, if the internal temperature change rate is greater than the preset temperature rise judgment value for a preset number of consecutive sampling cycles, the current hydration temperature stage is determined as the hydration temperature rise stage. As the hydration process continues, if the internal temperature change rate is still non-negative, but continues to decrease relative to the previous stage and continuously enters the preset temperature peak adjacent change range, and the current internal temperature reaches the preset adjacent range of the highest temperature of the previous curing stage, the hydration temperature rise stage is converted to the temperature peak adjacent stage.

[0097] The temperature peak proximity range can be set as the range where the internal temperature change rate is close to zero but has not yet formed a continuous downward trend. The preset proximity range of the stage's highest temperature is used to distinguish between the early slow heating state and the state that is truly close to the temperature peak, thereby avoiding premature judgment that the temperature peak proximity stage has been entered just because the internal temperature change rate is temporarily small.

[0098] When the rate of change of internal temperature in the phase near the temperature peak is less than the negative cooling judgment value for a preset number of consecutive sampling periods, it is determined that the internal temperature has passed the temperature peak, and the phase near the temperature peak is converted to the cooling phase after the temperature peak. When the internal temperature drops to a preset level relative to the recorded temperature peak after entering the cooling phase after the temperature peak, and the absolute value of the rate of change of internal temperature is lower than the preset stability judgment value for a preset number of consecutive sampling periods, and the internal-surface thermal state remains within the preset stable range, the phase after the cooling phase after the temperature peak is converted to the stable maintenance phase.

[0099] The threshold values ​​for the hydration heating stage, the temperature peak approach stage, the temperature peak cooling stage, and the stable curing stage can be pre-calibrated based on the hydraulic concrete mix proportion, structural thickness, cement and mineral admixture dosage, placement temperature, internal cooling pipeline layout, and construction season. The calibration data can be obtained from the adiabatic temperature rise test of concrete with the same mix proportion, on-site test chamber monitoring data, or historical curing data of similar hydraulic structures.

[0100] To further improve the stability of hydration temperature stage identification, a continuous confirmation condition is set before each stage transition. The stage transition is only performed after the judgment condition of the next stage is continuously satisfied for a preset number of sampling cycles. If the judgment condition of the next stage is only briefly satisfied within one or a few sampling cycles and then disappears, the current hydration temperature stage remains unchanged.

[0101] During the hydration and heating stage, the heat release from hydration inside the hydraulic concrete continues to increase, and the internal temperature usually rises faster than the near-surface temperature. At this time, the focus of regulation is to limit the excessive accumulation of internal heat and the continuous expansion of the internal-surface temperature difference, while maintaining the concrete surface in a moist state that meets the curing requirements.

[0102] When the hydration heating stage is underway and the internal-to-surface thermal state is low, the internal cooling water volume is kept at a low level to avoid excessive cooling in localized areas due to excessively high cooling water flow during the initial hydration phase. As the internal temperature continues to rise or the internal-to-surface thermal state increases, the internal cooling water volume is increased accordingly. The surface curing water volume is determined independently based on the current surface moisture evaporation driving state. When the evaporation driving state increases, the surface curing water volume is increased, rather than directly and synchronously increasing the internal cooling water volume due to increased surface water replenishment requirements.

[0103] Hydraulic concrete internal cooling and surface curing have different thermal and moisture response rates. When the internal cooling water flow rate changes, the area adjacent to the cooling pipe first exchanges heat with the cooling water, and then gradually affects the internal temperature detection area through internal heat conduction in the concrete. Therefore, the internal temperature has a response delay to changes in cooling water flow rate. Surface curing water acts directly on the surface of the hydraulic concrete or the area adjacent to the surface, and its impact on the near-surface thermal and moisture boundary is relatively faster. Therefore, in this embodiment, the internal cooling water volume, surface curing water volume, and target surface curing water temperature are not simply set to change rapidly and synchronously.

[0104] To determine the internal cooling response characteristics and surface curing response characteristics corresponding to the current hydration temperature stage, after entering a new hydration temperature stage, select collaborative control events that meet the preset adjustment range and record the time required for the internal cooling adjustment and surface curing adjustment to generate effective responses. Subsequently, the response time obtained from the most recent effective collaborative control event in the current hydration temperature stage is used as the current response characteristic of this stage. When a new effective collaborative control event is completed, the corresponding response time is updated.

[0105] For the In the secondary coordinated control event, when the internal cooling water volume is adjusted by a predetermined amount, the start time of the internal cooling adjustment is recorded, and the internal temperature and the rate of change of the internal temperature are continuously acquired. When the rate of change of the internal temperature relative to the average rate of change of the internal temperature before the adjustment reaches a preset magnitude, and this change is maintained for a preset number of sampling periods, it is determined that the internal cooling effect has formed an effective response, and the internal cooling response time is determined.

[0106] For the first Internal cooling response time corresponding to the secondary coordinated control event; For the first The moment when the preset internal response conditions are reached after internal cooling adjustment in a secondary coordinated control event; For the first The moment when internal cooling adjustments begin in a secondary coordinated control event; This refers to the sequence number of the coordinated control event.

[0107] The preset internal response conditions can be that the rate of change of internal temperature decreases by a predetermined amount after the internal cooling water volume is increased, or that the internal temperature forms a stable slowdown in the heating or cooling trend by continuously sampling for a preset number of cycles. The specific response conditions are preset according to the current hydration temperature stage and the direction of internal cooling adjustment.

[0108] In the same coordinated control event, when the surface curing water volume, the surface curing water supply method, or the target surface curing water temperature is adjusted by a predetermined range, the start time of the surface curing adjustment is recorded, and the near-surface temperature is continuously acquired. When the change in the near-surface temperature relative to the pre-adjustment level reaches the preset range, it is determined that the surface curing has formed an effective response, and the surface curing response time is determined.

[0109] For the first Surface maintenance response time corresponding to the secondary coordinated control event; For the first The moment when the preset surface response conditions are reached after surface maintenance adjustment in a secondary coordinated control event; For the first The moment when surface maintenance adjustments begin during a secondary coordinated control event; This refers to the sequence number of the coordinated control event.

[0110] The preset surface response conditions are set according to the degree of response of the near-surface temperature to the surface maintenance adjustment. For example, the change of the near-surface temperature relative to the temperature before adjustment can reach a preset temperature range and be continuously maintained for a preset number of sampling periods as a condition for the surface maintenance to form an effective response.

[0111] Within the same hydration temperature stage, the effective internal cooling response time and surface curing response time are used to determine the internal cooling-external curing coordination time:

[0112] For the first The coordination time of internal cooling and external nourishment corresponding to the secondary coordinated regulation event; For the first Internal cooling response time corresponding to the secondary coordinated control event; For the first Surface maintenance response time corresponding to the secondary coordinated control event; This refers to the sequence number of the coordinated control event; This is an operator that selects the larger value between the result calculated within the parentheses and zero.

[0113] When the internal cooling response time is greater than the surface curing response time, the surface curing regulation that will significantly enhance the near-surface cooling effect will be limited within the internal cooling-outer curing coordination time after increasing the internal cooling water volume, especially limiting the reduction of the target surface curing water temperature, but not stopping the surface curing.

[0114] When the surface moisture evaporation driving state increases during the internal cooling-external curing coordination time, the surface curing water volume is still increased according to the increased surface moisture evaporation driving state, and the humidification demand is not reduced due to the lag in the internal cooling response. While limiting the reduction of the target surface curing water temperature, the increased surface curing water volume is met by adjusting the supply flow rate of the surface curing water and / or extending the water supply duration, so that the increase in humidification volume and the enhancement of surface cooling effect are separated.

[0115] When the above process is simultaneously under surface cooling constraint, the surface curing water supply flow rate per unit time is further limited, and the corresponding surface curing water volume is met by extending the cumulative water supply duration within a control cycle, so as to avoid the near-surface temperature from dropping rapidly in advance due to a large instantaneous water supply before the internal cooling has formed an effective response.

[0116] After the internal cooling-external curing coordination time is reached, the internal temperature and near-surface temperature are obtained again. When the internal temperature change has reflected the effect of internal cooling adjustment, or when the internal-surface temperature difference stops expanding, the allowable curing water temperature difference between the surface curing water and the near-surface is re-determined based on the updated internal-surface thermal state and surface cooling constraint state. The target surface curing water temperature is then adjusted by regulating the mixing ratio of cooling return water and replenishing curing water.

[0117] When the difference between the internal cooling response time and the surface curing response time is less than the preset difference range, the internal cooling water flow rate, surface curing water volume, and target surface curing water temperature can be adjusted synchronously. When the surface coverage, spray distance, ambient humidity, or other curing boundary conditions make the surface curing response time not less than the internal cooling response time, the calculated internal cooling-external curing coordination time is zero, and no additional time limit for reducing the target surface curing water temperature is set.

[0118] After entering the stage near the temperature peak, the internal temperature has reached a relatively high level in the entire early-age maintenance process, and the rate of change of internal temperature gradually approaches zero. At this time, the focus of regulation changes from simply limiting the internal temperature rise to inhibiting the further expansion of the internal-surface temperature difference and avoiding excessively rapid cooling of the near-surface layer due to surface maintenance.

[0119] When the temperature is near the peak and the internal-surface thermal state is medium or high, maintain or increase the internal cooling water volume. At the same time, reduce the allowable temperature difference between the surface curing water and the near-surface curing water according to the internal-surface thermal state and the surface cooling constraint state, so that the target surface curing water temperature is closer to the near-surface temperature.

[0120] When the internal-surface thermal state reaches a high level near the temperature peak, the internal cooling water volume is preferentially increased to enhance internal heat exchange, rather than significantly reducing the target surface curing water temperature to enhance surface heat dissipation. When the surface moisture evaporation-driven state also reaches a high level, the surface curing water volume is increased according to this evaporation-driven state, and the target surface curing water temperature is maintained within a range adapted to the current near-surface thermal state. If a surface cooling constraint state is entered at this time, the increased surface curing water volume is maintained, and the instantaneous cooling effect of the surface curing water is reduced by limiting the supply flow rate and extending the water supply duration.

[0121] If the internal cooling water volume is increased near the temperature peak and the internal cooling response time is significantly longer than the surface curing response time, the internal cooling-external curing coordination time should be continued to limit the premature decrease of the target surface curing water temperature, so that the internal temperature change and the near-surface temperature change remain relatively coordinated.

[0122] Once it is confirmed that the hydraulic concrete has entered the cooling phase after reaching its temperature peak, the heat release from internal hydration gradually weakens, and the internal temperature begins to drop continuously. At this point, the focus of regulation shifts to limiting the rate of internal temperature drop and the rapid changes in the internal-surface thermal state, in order to prevent the internal temperature from dropping too quickly due to maintaining a high internal cooling water volume.

[0123] Only after the cooling phase following the temperature peak has been determined, the internal cooling rate is further determined based on the rate of internal temperature change:

[0124] For the first The internal cooling rate corresponding to the cooling phase after the temperature peak in each sampling period; For the first The rate of internal temperature change corresponding to each sampling period; The sampling period number; This is an operator that selects the larger value between the result calculated within the parentheses and zero.

[0125] During the hydration heating stage and the period near the temperature peak, the internal temperature drop in a single sampling cycle will not be used to determine the internal cooling water volume reduction based on the internal cooling rate, in order to avoid premature entry into the cooling control logic due to short-term environmental cooling, sensor fluctuations, or instantaneous changes in cooling water.

[0126] When the internal cooling rate exceeds the preset allowable cooling rate during the cooling phase after the temperature peak, the internal cooling water volume is reduced even if the current internal temperature is still at a high level. When the internal cooling rate does not exceed the preset allowable cooling rate and the internal-surface thermal state is still at a high level, the current internal cooling water volume is maintained. When the internal cooling rate gradually decreases and the internal-surface temperature difference continuously narrows, the internal cooling water volume is gradually reduced to avoid the internal cooling water volume from a high level to a low level or to stop internal cooling directly.

[0127] During the cooling phase after the temperature peak, the surface curing water volume continues to be determined based on the surface moisture evaporation driving state, and the internal-surface thermal state does not directly change the water replenishment demand determined by the evaporation driving state. When the ambient temperature decreases at night, accelerating the near-surface cooling and entering the surface cooling constraint state, the target surface curing water temperature is increased according to the internal-surface thermal state and the surface cooling constraint state, while the supply flow rate per unit time is limited; when the surface moisture evaporation driving state still requires maintaining a corresponding water replenishment volume, the surface curing water volume is met by extending the water supply duration.

[0128] When the ambient temperature rises and the ambient humidity decreases during the day, causing the surface moisture evaporation drive state to increase, the surface maintenance water volume should be increased accordingly. If the surface is not currently under surface cooling constraint, the supply flow rate and water supply duration can be adjusted according to the increased surface maintenance water volume. If the surface is under surface cooling constraint, the increased surface maintenance water volume should be maintained, and humidification should be prioritized by extending the water supply duration.

[0129] When hydraulic concrete enters the stable curing stage after the temperature peak, the internal temperature has decreased significantly relative to the peak temperature. The rate of internal temperature change remains within a small range, and the influence of internal hydration heat release on the overall temperature field gradually weakens. At this time, the internal cooling water volume is gradually reduced until the internal cooling circuit maintains the minimum cooling water flow or forced cooling is stopped.

[0130] The surface curing during the stable curing stage does not terminate synchronously with the cessation of internal cooling. The amount of surface curing water is still determined based on the driving state of surface moisture evaporation. When the ambient temperature and humidity conditions still cause the surface of the hydraulic concrete to show a significant tendency to lose water, surface moisturization continues, so that the conditions for the end of internal cooling and the conditions for the end of surface curing are independent of each other.

[0131] During the hydration heating stage, the temperature peak approach stage, the temperature peak cooling stage, and the stable curing stage, the internal-surface thermal state, the surface moisture evaporation driving state, and the surface cooling constraint state are continuously updated. The hydration temperature stage is used to adjust the control priority among the internal cooling water volume, the surface curing water volume, and the target surface curing water temperature.

[0132] For example, when a high evaporation-driven state occurs during the hydration heating stage, the surface curing water volume is increased according to the evaporation-driven state, and the internal cooling water volume is independently adjusted according to the internal-surface thermal state; when a high evaporation-driven state occurs near the temperature peak, the surface curing water volume is increased, while the target surface curing water temperature is limited to decrease according to the internal-surface thermal state and the surface cooling constraint state; when a high evaporation-driven state occurs during the cooling stage after the temperature peak, the surface curing water volume is increased, but the internal cooling water volume is limited according to the internal cooling rate, and the instantaneous surface cooling effect is reduced by extending the water supply duration when there is a surface cooling constraint; when a high evaporation-driven state occurs during the stable curing stage, the surface curing water continues to be supplied according to the surface humidification demand, without restoring a higher internal cooling water volume due to the increase in the evaporation-driven state.

[0133] Example 3 This embodiment uses the early-age curing process of a concrete test section of a hydraulic engineering dam pier as an example to illustrate the coordinated temperature and humidity control process of internal cooling, surface moisturization, and cooling return water mixing in hydraulic concrete. During continuous curing, the surface cooling constraint state is also judged based on near-surface temperature changes, and the water volume, water temperature, and supply method of the surface curing water are adjusted when the increase in moisturization demand and the surface cooling constraint occur simultaneously.

[0134] The test section of the gate pier is 11.8m long, 8.6m high, and 3.2m thick. It was poured continuously in the same batch, with a concrete design strength grade of C30. After pouring, it entered a continuous curing stage. Multiple internal temperature monitoring points were set up in the core area of ​​the gate pier, and multiple near-surface temperature monitoring points were set up 100mm from the surface to be cured. An environmental temperature and humidity monitoring unit was also set up approximately 300mm from the gate pier surface, avoiding direct spraying, to obtain data on internal temperature, near-surface temperature, ambient temperature, and ambient humidity.

[0135] Three sets of cooling pipes are pre-embedded inside the gate pier. Each set of cooling pipes can independently adjust the cooling water flow rate. The maximum allowable cooling water flow rate after the three sets of cooling pipes converge is 1.80 m³ / h. After the cooling return water flows into the main return water pipe, it is connected to the drainage branch and the surface curing water circuit through the branch pipes, so that at least part of the cooling return water can enter the surface curing water circuit. The surface curing water circuit is also connected to the supplementary curing water pipe. The cooling return water and the supplementary curing water are mixed by the mixing unit and then supplied to the atomizing nozzles installed on the surface of the gate pier. The maximum average water supply of the surface curing water circuit is 0.36 L / (m²·min). During the test, the average water supply per unit curing area represents the amount of surface curing water in each control cycle. The controller converts the average water supply into the actual total water supply in the corresponding control cycle according to the length of the control cycle.

[0136] In this embodiment, an internal-to-surface temperature difference of less than 8°C is defined as the basic range for low temperature difference, 8–15°C as the basic range for medium temperature difference, and greater than 15°C as the basic range for high temperature difference. When the internal-to-surface temperature difference has not yet entered the basic range corresponding to a higher level, but shows an increasing trend for three consecutive sampling cycles and the rate of temperature difference change reaches the preset growth condition, the internal-to-surface thermal state is advanced by one level.

[0137] Based on the surface water loss test results of the concrete test chamber with the same mix proportion, the surface moisture evaporation driving force is defined as low evaporation driving state if it is not higher than 1.50 kPa, medium evaporation driving state if it is greater than 1.50 kPa but not higher than 3.00 kPa, and high evaporation driving state if it is greater than 3.00 kPa.

[0138] The three internal-surface thermal state levels (low, medium, and high) correspond to different internal cooling water volumes, and the three surface moisture evaporation driving state levels (low, medium, and high) correspond to different surface curing water volumes. The surface curing water temperature is determined based on the internal-surface thermal state and the surface cooling constraint state.

[0139] During continuous curing, the near-surface temperature decrease rate is determined based on the near-surface temperature in adjacent sampling cycles. When this decrease rate reaches a preset cooling rate threshold, or when the internal-surface temperature difference shows a continuous increasing trend, a surface cooling constraint state is entered. Under the surface cooling constraint state, the surface curing water volume determined by the surface moisture evaporation driving state is not directly reduced. Instead, the near-surface cooling is limited by reducing the allowable curing water temperature difference and adjusting the supply flow rate and water supply duration.

[0140] After 12 hours of curing, the internal temperature was measured at 42.1℃, the near-surface temperature at 34.7℃, the internal-surface temperature difference at 7.4℃, the ambient temperature at 30.2℃, the relative humidity at 78%, and the surface moisture evaporation drive at 2.18 kPa. Therefore, the internal-surface thermal state was determined to be a low-temperature difference state, and the surface moisture evaporation drive state was determined to be a medium-temperature evaporation drive state. At this time, the internal cooling water flow rate was controlled at 0.63 m³ / h according to the low-temperature internal-surface thermal state, and the average surface water supply was controlled at 0.22 L / (m²·min) according to the medium-temperature evaporation drive state.

[0141] The temperature of the cooling return water was measured at 37.8℃ and the temperature of the replenishment maintenance water was measured at 21.6℃ in the 12th hour. Based on the current low temperature difference, the target surface maintenance water temperature was determined to be 28.7℃. The supply ratio of cooling return water and replenishment maintenance water was adjusted so that the cooling return water accounted for about 44% of the total surface maintenance water. The mixed surface maintenance water was intermittently supplied to the gate pier surface through atomizing nozzles.

[0142] After 30 hours of curing, the internal temperature rose to 47.8℃, the near-surface temperature was 36.3℃, the internal-surface temperature difference widened to 11.5℃, the ambient temperature was 33.4℃, the relative humidity was 61%, and the surface moisture evaporation drive was 2.90 kPa. At this point, the internal-surface thermal state entered a medium temperature difference state, while the surface moisture evaporation drive state remained a medium evaporation drive state. Increasing the internal cooling water flow rate from 0.63 m³ / h to 1.17 m³ / h did not change the level of the surface moisture evaporation drive state; therefore, the average surface water supply remained at 0.22 L / (m²·min).

[0143] The temperature of the cooling return water was 40.6℃ and the temperature of the replenished curing water was 22.1℃ after 30 hours of testing. Based on the medium temperature difference, the temperature of the target surface curing water was adjusted to 32.3℃. The cooling return water accounted for about 55% of the total surface curing water, which enhanced the internal cooling effect while reducing the temperature difference between the surface curing water and the near-surface layer.

[0144] By the 42nd hour of curing, the internal temperature reached 50.6℃, the near-surface temperature was 36.9℃, the internal-surface temperature difference reached 13.7℃, the ambient temperature rose to 34.1℃, the relative humidity decreased to 54%, and the surface moisture evaporation drive reached 3.35 kPa. Although the internal-surface temperature difference had not yet reached 15℃, multiple consecutive sampling cycles showed a continuous increase in the temperature difference, meeting the conditions for early escalation. Therefore, the internal-surface thermal state was treated as a high temperature difference state, and the surface moisture evaporation drive state was determined to be a high evaporation drive state.

[0145] At this point, based on the high-level internal-surface thermal state, the internal cooling water flow rate is increased to 1.80 m³ / h, and based on the high evaporation-driven state, the average surface water supply is increased from 0.22 L / (m²·min) to 0.32 L / (m²·min). Since the internal-surface temperature difference is still widening, the allowable temperature difference for the curing water is reduced when determining the target surface curing water temperature, and the target surface curing water temperature is controlled at approximately 34.9℃. This avoids using significantly lower-temperature curing water to enhance near-surface cooling while increasing the water supply.

[0146] The temperature of the cooling return water was 42.3℃ and the temperature of the replenishment curing water was 22.8℃ at the 42-hour mark. The supply ratio of the two water sources was adjusted so that the cooling return water accounted for about 62% of the total surface curing water. The surface curing water temperature was increased by utilizing some of the heat carried out from the inside of the concrete during the internal cooling process.

[0147] After the internal cooling water flow rate is increased from 1.17 m³ / h to 1.80 m³ / h, it takes a certain amount of time for the internal cooling effect to be transmitted to the internal temperature detection area. Therefore, during the internal cooling-external curing coordination time, the reduction of the target surface curing water temperature is limited, so that the mixed water temperature is temporarily maintained within the current target range. If the surface moisture evaporation-driven state still requires maintaining a surface curing water volume of 0.32 L / (m²·min) during this period, then this water replenishment volume will continue to be met, and the surface curing water volume will not be reduced due to the limitation of surface cooling effect.

[0148] During each sampling cycle of continuous maintenance, when the near-surface temperature drop rate reaches the preset cooling rate threshold, or when the internal-surface temperature difference continues to widen and a surface cooling constraint state is entered, the atomized water supply flow rate per unit time is limited, and the predetermined surface maintenance water volume is met by extending the cumulative water supply duration within the current control cycle. When the surface cooling constraint state is not entered, the water supply flow rate and water supply duration are adjusted normally according to the current surface maintenance water volume. Since the original experimental records did not separately statistically analyze the surface cooling constraint state at each representative control moment, this embodiment does not directly replace the surface cooling constraint determination results obtained from continuous sampling with discrete representative moments such as 12h, 30h, and 42h.

[0149] After 60 hours of curing, the internal temperature dropped to 48.9℃, the near-surface temperature was 37.6℃, the internal-surface temperature difference narrowed to 11.3℃, the ambient temperature was 31.2℃, the ambient relative humidity was 66%, and the surface moisture evaporation drive was 3.48kPa. Therefore, the internal-surface thermal state returned to a medium temperature difference state, while the surface moisture evaporation drive state remained at a high evaporation drive state.

[0150] At this point, the internal temperature has passed the temperature peak and entered the post-peak cooling stage. Based on the internal temperature change trend and the internal-surface thermal state, the cooling water flow rate is reduced from 1.80 m³ / h to 1.17 m³ / h. Since the surface moisture evaporation driving state is still at a high level, the average surface water supply continues to be maintained at 0.32 L / (m²·min).

[0151] The cooling return water temperature was 41.1℃ and the replenishment curing water temperature was 23.0℃ at 60h. The target surface curing water temperature was controlled at 33.6℃, ​​and the cooling return water accounted for approximately 59% of the total surface curing water.

[0152] By the 84th hour of curing, the internal temperature had decreased to 43.7℃, the near-surface temperature was 36.8℃, the internal-surface temperature difference had further narrowed to 6.9℃, the ambient temperature was 29.6℃, the ambient relative humidity was 72%, and the surface moisture evaporation drive was still 3.22 kPa. At this point, the internal-surface thermal state had decreased to a low temperature difference state, while the surface moisture evaporation drive state remained at a high evaporation drive state.

[0153] At this time, the internal cooling water flow rate gradually decreases as the internal-surface thermal state decreases. During this control period, the cooling water flow rate is adjusted to 0.80 m³ / h. The surface moisture evaporation drive state remains at a high level, therefore independent of the decrease in internal cooling water flow rate, and the average surface water supply continues to be maintained at 0.32 L / (m²·min). At the 84th hour, the cooling water return temperature was measured at 38.7℃, the replenishment curing water temperature at 22.5℃, and the target surface curing water temperature was controlled at 30.8℃. The cooling water return rate accounts for approximately 51% of the total surface curing water.

[0154] After 120 hours of curing, the internal temperature further decreased to 38.9℃, the near-surface temperature was 34.4℃, the internal-surface temperature difference was 4.5℃, the ambient temperature was 28.8℃, the ambient relative humidity was 76%, and the surface moisture evaporation driving force decreased to 2.43kPa. At this time, the internal-surface thermal state stabilized at a low temperature difference, and the surface moisture evaporation driving force returned to a medium evaporation driving force.

[0155] Based on the current internal-surface thermal state, the internal cooling water flow rate was further reduced to 0.63 m³ / h, and the average surface water supply was reduced from 0.32 L / (m²·min) to 0.22 L / (m²·min) based on the evaporation-driven state. At 120 hours, the cooling return water temperature was measured at 36.1℃, and the replenishment curing water temperature was 22.3℃. Based on the low temperature difference, the target surface curing water temperature was determined to be 28.4℃. The proportion of cooling return water to the total surface curing water was approximately 44%, ensuring that some cooling return water still entered the surface curing water path even during periods of low-level internal cooling operation.

[0156] The 12h, 30h, 42h, 60h, 84h, and 120h times mentioned above are representative control times selected from continuous maintenance monitoring data. Temperature and humidity parameters are continuously collected and adjusted according to a preset sampling cycle between adjacent representative control times. The main control states corresponding to each representative control time are shown in the table below:

[0157] The surface cooling constraint state is not listed separately in the table. The surface cooling constraint state is determined based on the continuous near-surface temperature and the trend of the internal-surface temperature difference between adjacent sampling periods. Its determination period is shorter than the time interval between the above-mentioned representative control moments. Therefore, it is determined in real time by continuous monitoring data, rather than directly based on the near-surface temperature at the above-mentioned discrete moments.

[0158] To verify the effect of cooperative temperature and humidity regulation, a conventional curing control section with the same concrete mix proportion, the same structural thickness, the same pouring time and similar external environmental conditions is set at an adjacent position. The internal cooling of the conventional curing control section is adjusted independently according to the internal temperature, the cooling water flow is changed when the internal temperature reaches a preset temperature condition, the surface curing is independently controlled according to the ambient relative humidity, and on-site supplementary curing water is directly used for spraying, without mixing the internal cooling return water into the surface curing water for temperature adjustment. At the same time, the conventional curing control section does not perform linkage constraint on the water supply flow per unit time and the water supply duration according to the near-surface cooling state.

[0159] The two test sections start monitoring synchronously after pouring is completed, and continuously record data until the hydraulic concrete enters a stable curing stage. To unify the statistical caliber of comparison data, the surface curing utilization rate of cooling return water is defined as the ratio of the cumulative amount of cooling return water introduced into the surface curing water circuit during the curing period to the cumulative amount of cooling return water discharged from the internal cooling circuit; the state in which a continuous downward-flowing visible water film is formed on the concrete surface and lasts for more than 1 minute is recorded as one obvious runoff process, and the duration of each obvious runoff process is accumulated; the maximum near-surface cooling rate is determined according to the maximum cooling change per unit time in the continuous near-surface temperature monitoring data. The obtained comparison data are shown in the following table:

[0160] Embodiment 4 This embodiment provides a temperature and humidity cooperative regulation system for hydraulic concrete curing, including a parameter acquisition module, a thermal state determination module, an evaporation driving determination module, a cooling constraint determination module, a cooperative decision-making module, an internal cooling regulation module, a water mixing and temperature regulation module, a surface curing module, a timing coordination module and a feedback regulation module.

[0161] The system is provided with a controller, which includes a processor and a memory. The thermal state determination module, the evaporation driving determination module, the cooling constraint determination module, the cooperative decision-making module, the timing coordination module and the feedback regulation module can be implemented by the processor executing the program stored in the memory. The parameter acquisition module is connected to the data input end of the controller, and the internal cooling regulation module, the water mixing and temperature regulation module and the surface curing module are connected to the control output end of the controller.

[0162] The internal cooling regulation module, the water mixing and temperature regulation module and the surface curing module are respectively provided with flow regulating devices for receiving the control signal of the controller, and the supply amount of internal cooling water, the mixing ratio of cooling return water and supplementary curing water, as well as the supply flow rate and water supply duration of surface curing water are changed through the regulation signal output by the controller.

[0163] The parameter acquisition module is used to acquire the internal temperature, near-surface temperature, ambient temperature, and ambient humidity of the hydraulic concrete, as well as the internal cooling water flow rate, cooling return water temperature and flow rate, replenishment curing water temperature and flow rate, mixed surface curing water temperature, and surface curing water supply flow rate. The internal temperature sensor is located in the core of the hydraulic concrete or at a location where hydration heat easily accumulates. The near-surface temperature sensor is located at a predetermined depth from the surface to be cured, and the ambient temperature and humidity sensor is located in the adjacent air region of the surface to be cured.

[0164] When multiple internal temperature detection points are set in the same maintenance area, the maximum value among the multiple internal temperature detection values ​​can be used as the current internal temperature; when multiple near-surface temperature detection points are set, the average value can be used as the current near-surface temperature after removing outliers.

[0165] The thermal state determination module is used to determine the internal-to-surface temperature difference based on the internal temperature and near-surface temperature, determine the rate of temperature difference change based on the internal-to-surface temperature difference corresponding to adjacent sampling periods, and determine the internal-to-surface thermal state based on the internal-to-surface temperature difference and the rate of temperature difference change. The internal-to-surface thermal state can be divided into low temperature difference state, medium temperature difference state, and high temperature difference state. When the rate of temperature difference change reaches a preset growth condition and is maintained for a preset number of sampling periods, the current internal-to-surface thermal state is increased by one level before the high temperature difference state is reached; when transitioning from a higher level to a lower level, the downgrade is executed after the corresponding downgrade condition is met consecutively.

[0166] The evaporation drive determination module is used to determine the saturated vapor pressure corresponding to the near-surface thermal state of the hydraulic concrete based on the near-surface temperature, determine the actual vapor pressure of the environment adjacent to the surface of the hydraulic concrete based on the ambient temperature and humidity, determine the surface moisture evaporation drive amount based on the difference between the saturated vapor pressure and the actual vapor pressure, and determine the surface moisture evaporation drive state based on the surface moisture evaporation drive amount. The surface moisture evaporation drive state can be divided into low evaporation drive state, medium evaporation drive state, and high evaporation drive state.

[0167] The cooling constraint determination module is used to determine the near-surface temperature decrease rate based on continuously sampled near-surface temperatures, and to determine the surface cooling constraint state based on the near-surface temperature decrease rate and the changing trend of the internal-surface temperature difference. When the near-surface temperature decrease rate reaches a preset cooling rate threshold, or when the internal-surface thermal state characterization shows a continuously increasing temperature difference between the interior and near-surface layers, the current state is determined as the surface cooling constraint state; when the corresponding condition disappears and is maintained for a preset number of sampling cycles, the surface cooling constraint state is exited.

[0168] The collaborative decision-making module is used to determine the internal cooling water volume based on the internal-surface thermal state, the surface curing water volume based on the surface moisture evaporation driving state, and the target surface curing water temperature based on the internal-surface thermal state and the surface cooling constraint state.

[0169] The internal cooling water volume and the surface curing water volume correspond to different state inputs. When the surface moisture evaporation driving state increases, the surface curing water volume can be increased, but the internal cooling water volume will not be directly changed due to the increase in the surface curing water volume. When the internal-surface thermal state increases, the internal cooling water volume can be increased, while the surface curing water volume is still determined according to the current surface moisture evaporation driving state.

[0170] The collaborative decision-making module is also used to determine whether surface humidification demand and near-surface cooling constraints exist simultaneously. When the surface moisture evaporation driving state increases, causing an increase in the surface curing water volume, and the cooling constraint determination module determines that the current state is under surface cooling constraint, the collaborative decision-making module maintains the increased surface curing water volume, while reducing the allowable temperature difference between the surface curing water and the near-surface layer, and outputs a supply mode adjustment command to the surface curing module to limit the unit time supply flow rate of the surface curing water and correspondingly extend the water supply duration.

[0171] The internal cooling regulation module includes a cooling circuit installed inside the hydraulic concrete and a flow regulation device for adjusting the cooling water flow. The controller controls the cooling water supply flow based on the current internal-surface thermal state and provides feedback adjustment based on the actual cooling water flow. After flowing through the hydraulic concrete, the cooling water forms cooling return water, which enters the drainage branch and the mixing and temperature regulation module through a diversion structure.

[0172] The internal cooling circuit can include multiple independent cooling branches. Each cooling branch is equipped with a flow regulating device at its inlet end to adjust the cooling water flow rate according to the internal-surface thermal state of different areas of the hydraulic concrete. The cooling return water discharged from each cooling branch flows into the cooling return water pipeline and then enters the diversion structure.

[0173] The mixing and temperature control module includes a first water inlet channel connected to the cooling return water, a second water inlet channel connected to the replenishment and maintenance water, and a mixing unit connected to both. The first water inlet channel and the second water inlet channel are respectively equipped with flow regulation devices.

[0174] The collaborative decision-making module determines the allowable temperature difference between the surface curing water and the near-surface layer of the hydraulic concrete based on the internal-surface thermal state and the surface cooling constraint state. It also determines the target surface curing water temperature based on the near-surface temperature and the allowable temperature difference. When the internal-surface thermal state level increases or the surface cooling constraint state is entered, the allowable temperature difference of the curing water is reduced, so that the target surface curing water temperature is closer to the near-surface temperature.

[0175] The controller limits the temperature of the maintenance water on the target surface to an adjustable range that can be achieved by the two water sources, based on the cooling return water temperature and the replenishment maintenance water temperature, and determines the mixing ratio of cooling return water and replenishment maintenance water accordingly. When the calculated cooling return water mixing ratio is lower than the preset minimum return water ratio, the cooling return water is used according to the minimum return water ratio, provided that the allowable maintenance water temperature range is met; when the cooling return water temperature is the same as the replenishment maintenance water temperature, the cooling return water is used according to the preset return water utilization ratio.

[0176] When the available cooling return water flow rate is lower than the cooling return water demand flow rate corresponding to the current mixing ratio, the surface curing water volume determined based on the current surface moisture evaporation drive state is maintained, and the insufficient cooling return water is supplemented by increasing the supplementary curing water flow rate. A curing water temperature detection unit is installed at the outlet of the mixing unit. When the deviation between the actual surface curing water temperature and the target temperature exceeds the preset range, the controller adjusts the supply ratio of the two water streams.

[0177] The surface curing module includes a surface curing water channel and multiple atomizing nozzles set along the surface of the hydraulic concrete to be cured. The controller controls the total water supply within a control cycle based on the surface water evaporation driving state, and distributes the total water supply to the corresponding control cycle by adjusting the supply flow rate and water supply duration of the surface curing water.

[0178] For vertical or inclined curing surfaces, intermittent spraying can be used to reduce surface runoff. When under surface cooling constraints, the controller limits the flow rate supplied per unit time by the atomizing nozzles and maintains the surface curing water volume corresponding to the current control cycle by increasing the number of water supply cycles and / or extending the cumulative water supply duration, so that the surface humidification demand is not reduced due to near-surface cooling constraints.

[0179] In one specific implementation, the collaborative decision-making module can also determine the internal temperature change trend based on the internal temperature obtained by continuous sampling, and determine the hydration heating stage, temperature peak approach stage, temperature peak cooling stage or stable curing stage of the hydraulic concrete based on the internal temperature change trend, and adjust the control priority between the internal cooling water volume, surface curing water volume and target surface curing water temperature according to the stage.

[0180] The timing coordination module is used to determine the internal cooling response time and the surface curing response time, and to determine the internal cooling-external curing coordination time based on the difference between the two. When the internal cooling response time is greater than the surface curing response time, the timing coordination module determines the internal cooling-external curing coordination time based on the time difference between the two, and sends a water temperature limit command to the collaborative decision-making module within the internal cooling-external curing coordination time to limit the reduction of the target surface curing water temperature.

[0181] When the surface moisture evaporation driving state increases during the internal cooling-external curing coordination time, the surface curing water volume is still determined according to the increased surface moisture evaporation driving state; if it is simultaneously under the surface cooling constraint state, the corresponding surface curing water volume is met by limiting the supply flow rate per unit time and extending the water supply duration, instead of enhancing near-surface cooling by further reducing the target surface curing water temperature.

[0182] Once the internal cooling-external curing coordination time is reached, the internal temperature and near-surface temperature are reacquired, and the target surface curing water temperature is re-determined based on the updated internal-surface thermal state and surface cooling constraint state. The mixing water temperature control module readjusts the mixing ratio of cooling return water and replenishing curing water according to the updated target surface curing water temperature.

[0183] The feedback adjustment module acquires the updated internal temperature, near-surface temperature, and ambient temperature and humidity according to the preset sampling period, and inputs the updated parameters into the thermal state determination module, evaporation drive determination module, and cooling constraint determination module respectively to update the internal-surface thermal state, surface moisture evaporation drive state, and surface cooling constraint state.

[0184] The feedback adjustment module readjusts the internal cooling water volume, surface curing water volume, and target surface curing water temperature based on the updated three states, and sends the updated target surface curing water temperature to the mixing and temperature control module to redetermine the mixing ratio of cooling return water and replenishment curing water. The internal cooling adjustment module, mixing and temperature control module, and surface curing module execute the internal cooling, mixing and temperature control, and surface water supply for the next control cycle according to the updated control values.

[0185] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for coordinated temperature and humidity control in the curing of hydraulic concrete, characterized in that, Includes the following steps: S1. Obtain the internal temperature, near-surface temperature, and ambient temperature and humidity of the hydraulic concrete; S2. Determine the internal-surface thermal state based on the internal temperature and the near-surface temperature, determine the surface moisture evaporation driving state based on the near-surface temperature and the ambient temperature and humidity, and determine the surface cooling constraint state based on the change in the near-surface temperature. S3. Determine the internal cooling water volume based on the internal-surface thermal state, determine the surface curing water volume based on the surface moisture evaporation driving state, and determine the target surface curing water temperature based on the internal-surface thermal state and the surface cooling constraint state. S4. When the surface curing water volume increases and the surface is under a surface cooling constraint, the increased surface curing water volume is maintained, and the near-surface cooling is limited by adjusting the target surface curing water temperature and the surface curing water supply method. S5. Mix at least a portion of the cooling return water generated by internal cooling with the replenishing curing water, adjust the mixing ratio of the two according to the target surface curing water temperature, and supply water to the surface of the hydraulic concrete according to the surface curing water volume. S6. Determine the internal cooling-external curing coordination time based on the time difference between the internal cooling response and the surface curing response, and limit the reduction of the target surface curing water temperature within the internal cooling-external curing coordination time. S7. Based on the updated internal-surface thermal state, surface moisture evaporation driving state, and surface cooling constraint state, adjust the internal cooling water volume, surface curing water volume, target surface curing water temperature, and the mixing ratio.

2. The method for coordinated temperature and humidity control for hydraulic concrete curing according to claim 1, characterized in that, In step S2, determining the internal-surface thermal state includes: The internal-to-surface temperature difference is determined based on the internal temperature and the near-surface temperature, and the rate of change of the temperature difference is determined based on the internal-to-surface temperature difference corresponding to adjacent sampling periods. The internal-surface temperature difference is compared with a preset first temperature difference threshold and a second temperature difference threshold to determine a low temperature difference state, a medium temperature difference state, or a high temperature difference state, wherein the first temperature difference threshold is less than the second temperature difference threshold. When the internal-surface thermal state determined based on the internal-surface temperature difference does not reach the high temperature difference state, and the rate of change of the temperature difference reaches a preset growth threshold and is continuously maintained for a preset number of sampling periods, the internal-surface thermal state is raised by one level.

3. The method for coordinated temperature and humidity control for hydraulic concrete curing according to claim 1, characterized in that, In step S2, the saturated water vapor pressure corresponding to the near-surface thermal state of the hydraulic concrete is determined based on the near-surface temperature, and the actual water vapor pressure of the environment adjacent to the surface of the hydraulic concrete is determined based on the ambient temperature and humidity. The surface moisture evaporation driving amount is determined based on the difference between the saturated vapor pressure and the actual vapor pressure, and the surface moisture evaporation driving state is determined based on the surface moisture evaporation driving amount.

4. The method for coordinated temperature and humidity control for hydraulic concrete curing according to claim 1, characterized in that, In step S2, the internal-to-surface temperature difference is determined based on the internal temperature and the near-surface temperature, the internal-to-surface temperature difference change trend is determined based on the internal-to-surface temperature difference obtained by continuous sampling, and the near-surface temperature decrease rate is determined based on the near-surface temperature obtained by continuous sampling. The surface cooling constraint state is determined based on the near-surface temperature decrease rate and the internal-surface temperature difference change trend. When the near-surface temperature decrease rate reaches a preset cooling rate threshold, or when the internal-surface temperature difference shows an increasing trend, the surface cooling constraint state is entered.

5. The method for coordinated temperature and humidity control for hydraulic concrete curing according to claim 1, characterized in that, In step S3, the surface moisture evaporation driving state is divided into multiple levels, and the surface maintenance water volume within a control cycle is determined according to the level of the surface moisture evaporation driving state. The allowable temperature difference between the surface curing water and the near-surface layer of the hydraulic concrete is determined based on the internal-surface thermal state and the surface cooling constraint state, and the target surface curing water temperature is determined based on the near-surface temperature and the allowable temperature difference.

6. The method for coordinated temperature and humidity control for hydraulic concrete curing according to claim 5, characterized in that, In step S4, when the surface moisture evaporation driving state increases and the surface maintenance water volume increases within a control cycle, and the surface is under the surface cooling constraint state, the unit time supply flow rate of the surface maintenance water is limited, and the water supply duration within the control cycle is extended to maintain the surface maintenance water volume corresponding to the increased surface moisture evaporation driving state.

7. The method for coordinated temperature and humidity control for hydraulic concrete curing according to claim 5, characterized in that, In step S5, the temperature of the cooling return water and the temperature of the replenishment maintenance water are obtained, the temperature of the target surface maintenance water is limited to an adjustable temperature range formed by the cooling return water temperature and the replenishment maintenance water temperature, and the mixing ratio of the cooling return water and the replenishment maintenance water is determined according to the limited target surface maintenance water temperature. When the available cooling return water is insufficient to meet the cooling return water demand corresponding to the mixing ratio, the surface maintenance water is supplemented by the supplementary maintenance water.

8. The method for coordinated temperature and humidity control for hydraulic concrete curing according to claim 1, characterized in that, The internal temperature change trend is determined based on the internal temperature obtained from continuous sampling, and the hydration heating stage, temperature peak approach stage, temperature peak cooling stage or stable curing stage of the hydraulic concrete is determined based on the internal temperature change trend. The control priority among the internal cooling water volume, surface curing water volume, and target surface curing water temperature is adjusted according to the hydration heating stage, the temperature peak approach stage, the temperature peak cooling stage, or the stable curing stage.

9. The method for coordinated temperature and humidity control for hydraulic concrete curing according to claim 1, characterized in that, In step S6, the internal cooling response time corresponding to the internal temperature reaching the preset internal response condition after internal cooling adjustment and the surface curing response time corresponding to the near-surface temperature reaching the preset surface response condition after surface curing adjustment are determined respectively. When the internal cooling response time is greater than the surface curing response time, the internal cooling-external curing coordination time is determined based on the time difference between the two, and the reduction of the target surface curing water temperature is restricted within the internal cooling-external curing coordination time; when the surface moisture evaporation driving state increases within the internal cooling-external curing coordination time, the corresponding surface curing water volume is met by increasing the supply flow rate of surface curing water and / or extending the water supply duration.

10. A temperature and humidity coordinated control system for the curing of hydraulic concrete, characterized in that, include: The parameter acquisition module is used to acquire the internal temperature, near-surface temperature, and ambient temperature and humidity of the hydraulic concrete. A thermal state determination module is used to determine the internal-surface thermal state based on the internal temperature and the near-surface temperature. An evaporation drive determination module is used to determine the surface moisture evaporation drive state based on the near-surface temperature and ambient temperature and humidity. A cooling constraint determination module is used to determine the surface cooling constraint state based on the change in the near-surface temperature. The collaborative decision-making module is used to determine the internal cooling water volume based on the internal-surface thermal state, determine the surface curing water volume based on the surface moisture evaporation driving state, determine the target surface curing water temperature based on the internal-surface thermal state and the surface cooling constraint state, and maintain the increased surface curing water volume and adjust the target surface curing water temperature and the surface curing water supply method when the surface curing water volume increases and is under the surface cooling constraint state. An internal cooling regulation module is used to regulate the supply of cooling water inside the hydraulic concrete according to the internal cooling water volume. A water mixing and temperature control module is used to mix at least a portion of the cooling return water generated by internal cooling with the replenishment maintenance water, and to adjust the mixing ratio of the cooling return water and the replenishment maintenance water according to the temperature of the maintenance water on the target surface. A surface curing module is used to supply mixed surface curing water to the surface of hydraulic concrete according to the surface curing water volume; The timing coordination module is used to determine the internal cooling-external curing coordination time based on the time difference between the internal cooling response and the surface curing response, and to limit the reduction of the target surface curing water temperature within the internal cooling-external curing coordination time. The feedback adjustment module is used to adjust the internal cooling water volume, surface curing water volume, target surface curing water temperature, and mixing ratio based on the updated internal-surface thermal state, surface moisture evaporation driving state, and surface cooling constraint state.

Images