An order demand-based energy-saving and carbon-reducing concrete beam intelligent prefabrication method

Abstract

The application discloses an energy-saving and carbon-reducing concrete beam intelligent prefabrication method based on order demand, which dynamically calculates optimal tensioning time and tensioning control value of batch tensioning through an intelligent platform algorithm model based on order demand. The core steps include: parameter initialization and input order; real-time monitoring of concrete temperature and environmental temperature, and strength development prediction based on concrete maturity theory; and calculation of optimal tensioning opportunity with the minimum total cost as the target, which comprehensively considers energy consumption cost and equipment operation cost. Through real-time dynamic optimization, the application effectively solves the problems of high energy consumption of steam curing, long production cycle caused by experience-dependent tensioning opportunity, and low pedestal turnover rate in the traditional prefabrication method, and realizes energy-saving, carbon-reducing, intelligent and efficient prefabrication production.

Description

Technical Field

[0001] This invention belongs to the field of bridge engineering construction technology, and in particular, it is a smart prefabrication method for energy-saving and carbon-reducing concrete beams based on order requirements. Background Technology

[0002] Precast concrete beams are key components widely used in infrastructure such as bridges and buildings. Their production process typically includes critical steps such as rebar tying, concrete pouring, steam curing, and prestressing tensioning. Among these, steam curing is the main source of energy consumption and carbon emissions, while the timing of prestressing tensioning directly determines the beam's quality, production cycle, and prestressing platform turnover efficiency. Currently, the precast beam curing and tensioning methods commonly used in the industry mainly suffer from the following problems:

[0003] (1) The curing process is extensive, resulting in high energy consumption and carbon emissions: Traditional steam curing often adopts a fixed time-temperature regime, lacking dynamic adjustments based on ambient temperature, beam specifications, and material properties. This "one-size-fits-all" approach easily leads to energy waste, such as prolonged steam curing even when the temperature is high or the beam is small, causing a large amount of unnecessary fuel consumption and carbon emissions. Although existing technologies can calculate basic energy consumption, they fail to combine real-time dynamic thermal analysis with order delivery requirements to achieve precise energy-saving control.

[0004] (2) The timing of tensioning relies on experience and lacks intelligence: The prestressing tensioning time is usually determined based on the strength test results of concrete specimens cured under the same conditions. This method has a serious lag and cannot reflect the real development of the concrete strength inside the beam in real time. To ensure safety, operators often tend to extend the curing time and tension the prestressed concrete after the strength has fully developed. This leads to an extension of the production cycle and a reduction in the turnover rate of precast platforms, increasing equipment occupation and site costs.

[0005] (3) Disconnection between cost control and quality control: Existing production management often treats quality control and cost control as two separate links. The production department aims to ensure strength, while the cost department conducts post-event accounting. There is a lack of an integrated model that can dynamically calculate and optimize the total cost in real time under the hard constraints of ensuring concrete strength (such as meeting early tension strength and final strength), thus failing to achieve the optimal balance between quality and efficiency.

[0006] (4) Failure to effectively support flexible production based on orders: With the development of industrialized construction, the production of precast components is showing a trend of small batches and multiple specifications. Existing methods are unable to quickly respond to the personalized needs of different orders in terms of delivery time, beam specifications, tension control values, etc., and cannot dynamically calculate the optimal production plan (such as steam curing time, tensioning time, etc.) to meet the requirements of specific orders, which restricts the level of intelligence and precision in precast production.

[0007] Therefore, there is an urgent need in this field for an intelligent algorithm model that can deeply integrate order demand, real-time monitoring, strength prediction, energy consumption analysis and cost optimization, so as to significantly reduce energy consumption and carbon emissions, shorten the production cycle and achieve energy saving, carbon reduction, high efficiency and intelligence in the prefabrication process of concrete beams while ensuring the quality of concrete beams. Summary of the Invention

[0008] The purpose of this invention is to address the defects or deficiencies of the existing technology by providing an intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order requirements.

[0009] The technical solution for achieving the objective of this invention is as follows: an intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order requirements. This method, through an algorithm model embedded in an intelligent platform, dynamically determines the optimal production parameters based on order requirements. The optimal production parameters include the optimal tensioning time and tensioning control value for batch tensioning. The method includes the following steps:

[0010] Step 1: Obtain order information, automatically calculate the geometric characteristic parameters of the beam to be precast, retrieve the material parameters of the beam to be precast, and determine the target curing temperature, target strength, and batch tensioning time according to the delivery schedule; the target strength includes the initial tensile strength of the concrete. Concrete design strength ;

[0011] Step 2: Monitor concrete temperature and ambient temperature in real time, and dynamically predict the real-time evolution data of current concrete strength based on concrete maturity theory.

[0012] Step 3: With the goal of minimizing total cost, the optimal steam curing time and corresponding optimal production parameters are dynamically calculated while satisfying the preset concrete strength constraints, and an execution command is issued to the tensioning equipment.

[0013] Further, in step 1, the geometric feature parameters include the mass m and surface area A of the beam to be precast; the material parameters include the specific heat capacity c and heat transfer coefficient U of concrete; and the order information includes the delivery time, beam specifications, material parameters, and prestressing parameters.

[0014] Further, in step 2, the concrete strength is predicted using the concrete maturity-strength relationship curve; wherein, the concrete maturity-strength relationship curve is expressed as:

[0015]

[0016] In the formula, Indicates concrete strength; The value represents the ultimate strength of concrete, in MPa; k represents the strength growth coefficient, which is a constant; t represents the steam curing time, in hours. The maturity of concrete is expressed as:

[0017]

[0018] In the formula, For real-time monitoring of concrete temperature, To monitor the ambient temperature in real time, This is the total time of hydration heat time and steam curing time t during the early age of concrete.

[0019] Furthermore, in step 3, it is necessary to monitor in real time whether the current concrete strength meets the following conditions:

[0020]

[0021] If satisfied, the total energy consumption at the current moment is calculated immediately. and total cost ;

[0022] In the formula, The current concrete strength. This refers to the initial tensile strength of the concrete.

[0023] Furthermore, in step 3, the expression for the total cost is:

[0024]

[0025] In the formula, For total cost, For energy consumption costs, Operating costs.

[0026] Furthermore, the energy consumption cost The calculation formula is as follows:

[0027]

[0028] In the formula, For energy unit price, Total energy consumption;

[0029] The operating costs The calculation formula is as follows:

[0030]

[0031] In the formula, To set a fixed start-up cost, t represents the steam curing time. Let r be the time constant and r be the equipment operating cost rate.

[0032] Furthermore, the total energy consumption The calculation formula is:

[0033]

[0034] in, The energy consumption for heating and steam curing is expressed as:

[0035]

[0036] To maintain the energy consumption during the phase, it is expressed as:

[0037]

[0038] In the formula, c is the specific heat capacity of concrete, and m is the mass of the concrete beam. The target curing temperature for concrete. The ambient temperature changes over time. The system's overall efficiency coefficient, and >1; U is the comprehensive heat transfer coefficient of the curing shed and template, and A is the heat dissipation surface area of ​​the protective structure.

[0039] Furthermore, in step 3, the optimal steam curing time... The solution is as follows:

[0040] If detected This shortens the optimal steam curing time. ;

[0041] like Then extend the optimal steam curing time. ;

[0042] like ,but .

[0043] Furthermore, in step 3, issuing the execution instruction specifically includes:

[0044] Initial tensioning: when the optimal steam curing time is reached. And satisfy Then, a "first tensioning" command is sent to the tensioning equipment;

[0045] Secondary tensioning: After the first tensioning is completed, the beam is moved, and natural curing is used to allow the concrete strength to reach 100% of the concrete design strength. Then, a second tensioning is performed to establish the final prestress.

[0046] Furthermore, the formula for calculating the tension control force F during the initial tensioning is based on a mechanical equilibrium model:

[0047]

[0048]

[0049] in, , , , ;

[0050] In the formula, G is the self-weight of the precast concrete structure. Where is the prestressed steel strand rotation angle, h is the distance from the anchor point of the steel strand to the centroid of the section, and L is the length of the concrete structure. D is the distance between the bending point of the steel strand and the beam end, and D is the distance between the straight point of the steel strand and the beam end. Turning radius of steel strands.

[0051] Compared with the prior art, the significant advantages of this invention are:

[0052] (1) By establishing a dynamic energy consumption model and monitoring the ambient temperature and concrete temperature in real time, the minimum heat input required to achieve the target strength can be accurately calculated and optimized. With the goal of minimizing total cost, the system automatically decides the optimal steam curing time, fundamentally avoiding energy waste and achieving precise control of energy saving, consumption reduction and carbon reduction.

[0053] (2) By using the concrete maturity theory to predict the actual strength of the beam in real time, the tensioning command can be automatically issued as soon as the strength reaches the standard. This not only ensures the timeliness and safety of the tensioning operation, but also significantly shortens the production cycle of a single beam and significantly improves the turnover efficiency of key resources such as precast platforms, curing sheds and tensioning equipment, thereby achieving "quality improvement and efficiency enhancement".

[0054] (3) A dynamic optimization decision-making mechanism with the goal of minimizing total cost was introduced. Under the premise of ensuring the concrete strength as a hard constraint, the relationship between energy consumption cost and equipment operation and platform occupation cost was dynamically weighed to find the best balance point. The optimal solution with the lowest comprehensive cost under the order delivery requirements was found, realizing refined management and achieving integrated dynamic optimization of quality, cost and schedule.

[0055] (4) Through accurate strength prediction and scientific mechanical model, the prestress required to offset its own weight in the early age can be accurately calculated, providing an accurate and reliable theoretical basis and safety guarantee for the initial tensioning, and avoiding quality problems such as early cracking or excessive prestress loss.

[0056] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0057] Figure 1This is a flowchart illustrating the intelligent algorithm model for energy-saving and carbon-reducing concrete beams based on order requirements.

[0058] Figure 2 Energy consumption cost of the present invention in one embodiment Equipment operating costs With total cost Relationship diagram.

[0059] Figure 3 This is a schematic diagram of the precast concrete structure of the present invention in one embodiment.

[0060] Reference numerals: 1—precast concrete, 2—prestressed steel strand. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0062] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0063] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0064] In one embodiment, an intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order demand is provided. This method uses an algorithm model embedded in an intelligent platform to dynamically determine optimal production parameters based on order demand. These optimal production parameters include optimal tensioning time and tensioning control values ​​for batch tensioning. The objective is to find the total cost... The minimum value, that is, the total cost that satisfies the tensioning requirements. Minimum, and corresponding total energy consumption Reasonably, the cost is relatively low, thereby achieving the goals of energy saving, carbon reduction, and intelligent prefabrication.

[0065] Combination Figures 1 to 3 The method includes the following steps:

[0066] Step 1: Obtain order information, automatically calculate the geometric characteristic parameters of the beam to be precast, retrieve the material parameters of the beam to be precast, and determine the target curing temperature, target strength, and batch tensioning time according to the delivery schedule; the target strength includes the initial tensile strength of the concrete. Concrete design strength ;

[0067] Here, the geometric characteristic parameters include information such as the mass m of the precast beam, surface area A, and the amount of concrete and steel reinforcement used; the material parameters include the specific heat capacity c of concrete and the heat transfer coefficient U; the order information includes the delivery time, beam specifications, material parameters, and prestressing parameters.

[0068] Step 2: Monitor concrete temperature and ambient temperature in real time, and dynamically predict the real-time evolution data of current concrete strength based on concrete maturity theory.

[0069] Step 3: With the goal of minimizing total cost, the optimal steam curing time and corresponding optimal production parameters are dynamically calculated while satisfying the preset concrete strength constraints, and an execution command is issued to the tensioning equipment.

[0070] Furthermore, in one embodiment, in step 2, the concrete strength is predicted using a concrete maturity-strength relationship curve; wherein the concrete maturity-strength relationship curve is expressed as:

[0071]

[0072] In the formula, Indicates concrete strength; The value represents the ultimate strength of concrete, in MPa; k represents the strength growth coefficient, which is a constant; t represents the steam curing time, in hours. The maturity of concrete is expressed as:

[0073]

[0074] In the formula, The concrete temperature is monitored in real time using, but is not limited to, temperature sensors. To monitor the ambient temperature in real time, This is the total time of hydration heat time and steam curing time t during the early age of concrete.

[0075] Here is the concrete maturity-strength relationship curve. The strength development data of precast concrete under different constant temperature conditions (e.g., C50 concrete at 20°C, 30°C, 40°C, 50°C, 60°C, and 70°C) were obtained through laboratory standard test blocks, but not limited to these tests. The time-strength data at different temperatures were then fitted to obtain the concrete maturity-strength curve. .

[0076] Furthermore, in one embodiment, in step 3, it is necessary to monitor in real time whether the current concrete strength meets the following conditions:

[0077]

[0078] If satisfied, the total energy consumption at the current moment is calculated immediately. and total cost ;

[0079] In the formula, The current concrete strength. This refers to the initial tensile strength of the concrete.

[0080] Preferably, in some embodiments, in step 3, the expression for the total cost is:

[0081]

[0082] In the formula, For total cost, For energy consumption costs, Operating costs.

[0083] Here, total cost Minimization is achieved by optimizing steam curing time, steam curing temperature, and tensioning timing, in order to reduce energy consumption costs while ensuring quality. With equipment operating costs .

[0084] In step 3, the total cost under the premise of meeting the tensioning requirements. Minimum, meaning simultaneously meeting the current concrete strength requirements. With total cost Minimum; among which, the initial tensile strength of concrete Generally, it is 70% to 80% of the concrete design strength. The model system then sends commands to the tensioning equipment.

[0085] More specifically: if the current concrete strength Calculate the total energy consumption up to the current time t. and corresponding total cost When the total cost is discovered Being at its minimum means that further increasing the steam curing time will increase energy consumption costs. This shortens the early-age prestressing tensioning time of concrete and improves the turnover efficiency of precast pedestals; similarly, when the model system discovers the total cost At its minimum, reducing the steam curing time will reduce energy consumption costs. This increases the natural curing time of concrete in its early stages, while also increasing the costs associated with the use of precast concrete platforms, curing sheds, and labor. .

[0086] Preferably, in some embodiments, the energy consumption cost The calculation formula is as follows:

[0087]

[0088] In the formula, The price is the unit price of energy, expressed in ten thousand yuan / kJ. Total energy consumption, expressed in kJ;

[0089] The operating costs The calculation formula is as follows:

[0090]

[0091] In the formula, The fixed start-up cost is expressed in ten thousand yuan, and t represents the steam curing time. Here, is the time constant in hours (h), and r is the equipment operating cost rate in ten thousand yuan per hour (h). The time constant... In typical scenarios, the value is 8h. t and The relationship between the two is that they jointly determine the operating cost allocation curve; t≈ The optimal steam curing time is t, if t is much smaller than t. If t is much larger than 1, then more equipment needs to be started, making the equipment the primary factor and resulting in higher equipment operating costs; In this case, energy consumption costs are dominant, fewer devices are turned on, and equipment operating costs are low.

[0092] Preferably, in some embodiments, the total energy consumption The calculation formula is:

[0093]

[0094] in, The energy consumption for heating and steam curing is expressed as:

[0095]

[0096] To maintain the energy consumption during the phase, it is expressed as:

[0097]

[0098] In the formula, c is the specific heat capacity of concrete, in kJ / (kg·°C), and m is the mass of the concrete beam, in kg. The target curing temperature for concrete, expressed in °C. The ambient temperature varies over time, expressed in °C. The system's overall efficiency coefficient, and >1; U is the overall heat transfer coefficient of the curing shed and template, in kW / (m²·°C), and A is the heat dissipation surface area of ​​the protective structure, in m².

[0099] It should be noted that the steam curing of small box girders is generally carried out in a steam curing shed. The target temperature of the steam curing shed is usually a set constant, such as 40℃, 50℃, 60℃, etc. The ambient temperature changes over time. Since the temperature in the steam curing shed changes little over a short period of time, this change can be ignored. At this time, the ambient temperature can be considered as a constant temperature. If the temperature changes significantly within a day, the energy consumption for steam curing needs to be considered in an integral form.

[0100] Preferably, in some embodiments, in step 3, the optimal steam curing time is... The solution is as follows:

[0101] If detected This shortens the optimal steam curing time. ;

[0102] like Then extend the optimal steam curing time. ;

[0103] like ,but .

[0104] Preferably, in some embodiments, step 3, issuing the execution instruction specifically includes:

[0105] Initial tensioning: when the optimal steam curing time is reached. And satisfy Then, a "first tensioning" command is sent to the tensioning equipment;

[0106] Secondary tensioning: After the first tensioning is completed, the beam is moved, and natural curing is used to allow the concrete strength to reach 100% of the concrete design strength. Then, a second tensioning is performed to establish the final prestress.

[0107] Here, concrete strength This will limit the shortest steam curing time, therefore the optimal steam curing time Should meet the requirements Time has One option is to lay one sheet, then move the beam, and allow the concrete to cure naturally until it reaches 100% of its design strength. Two sheets will be drawn.

[0108] Here, shortening the early-age prestressing tensioning time of concrete involves the issue of secondary prestressing tensioning in early-age precast concrete structures. The first tensioning occurs when the concrete strength reaches a certain level. When to carry out, corresponding to the concrete strength Generally, the initial prestressing is 70% to 80% of the design strength to offset the self-weight and early shrinkage stress, corresponding to the initial prestressing ensuring zero camber in the concrete structure; secondary prestressing is performed when the concrete strength reaches a higher standard. Then, corresponding to the concrete strength. To achieve 100% design strength, the final prestressing is established.

[0109] Furthermore, the resultant force of the vertical component of the initial tension force F at early age counteracts the structure's self-weight, corresponding to the following tension force F for the steel strands:

[0110]

[0111]

[0112] in, , , , ;

[0113] In the formula, G is the self-weight of the precast concrete structure. Where is the prestressed steel strand rotation angle, h is the distance from the anchor point of the steel strand to the centroid of the section, and L is the length of the concrete structure. D is the distance between the bending point of the steel strand and the beam end, and D is the distance between the straight point of the steel strand and the beam end. Turning radius of steel strands.

[0114] The initial prestressing strength corresponding to the initial tension force F of the early-age steel strand in concrete is: The final tensile strength of the prestressed material. 100% design tensile stress .

[0115] The method is implemented through an intelligent platform algorithm model, which integrates parameter initialization, real-time monitoring, intensity prediction, cost analysis and dynamic decision-making functions. The input and output tables of the corresponding algorithm model are shown in Table 1 and Table 2 below.

[0116] Table 1 Input Table

[0117]

[0118] Table 2 Output Table

[0119]

[0120] In one embodiment, an intelligent prefabrication system for energy-saving and carbon-reducing concrete beams based on order demand is provided, the system comprising:

[0121] The first module is used to: acquire order information, automatically calculate the geometric characteristic parameters of the beam to be precast, retrieve the material parameters of the beam to be precast, and determine the target curing temperature, target strength, and batch tensioning time according to the delivery schedule; the target strength includes the initial tensile strength of the concrete. Concrete design strength ;

[0122] The second module is used to: monitor concrete temperature and ambient temperature in real time, and dynamically predict the real-time evolution data of the current concrete strength based on the concrete maturity theory.

[0123] The third module is used to: take the minimization of total cost as the objective function, dynamically calculate the optimal steam curing time and the corresponding optimal production parameters under the condition of satisfying the preset concrete strength constraints, and issue execution instructions to the tensioning equipment.

[0124] Specific limitations regarding the intelligent prefabrication system for energy-saving and carbon-reducing concrete beams based on order requirements can be found in the limitations of the intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order requirements mentioned above, and will not be repeated here. Each module in the aforementioned intelligent prefabrication system for energy-saving and carbon-reducing concrete beams based on order requirements can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the corresponding operations of each module.

[0125] In one embodiment, an intelligent algorithm model for energy saving and carbon reduction of concrete beams is provided. The model is integrated into an intelligent platform. By establishing a correlation between a dynamic energy consumption model and a concrete maturity model, and taking the minimization of total cost as the convergence condition, the model dynamically outputs the optimal curing temperature regime and tensioning timing decision instructions that meet the order delivery date constraints.

[0126] In one embodiment, an intelligent algorithm model for energy-saving and carbon-reducing concrete beams based on order demand is provided. The model is applied to the intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order demand. The model balances the increase in energy costs caused by prolonged steam curing time with the increase in platform turnover costs caused by shortened steam curing time, and outputs production parameter instructions that bring the comprehensive cost curve to a minimum point.

[0127] In one embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements:

[0128] Step 1: Obtain order information, automatically calculate the geometric characteristic parameters of the beam to be precast, retrieve the material parameters of the beam to be precast, and determine the target curing temperature, target strength, and batch tensioning time according to the delivery schedule; the target strength includes the initial tensile strength of the concrete. Concrete design strength ;

[0129] Step 2: Monitor concrete temperature and ambient temperature in real time, and dynamically predict the real-time evolution data of current concrete strength based on concrete maturity theory.

[0130] Step 3: With the goal of minimizing total cost, the optimal steam curing time and corresponding optimal production parameters are dynamically calculated while satisfying the preset concrete strength constraints, and an execution command is issued to the tensioning equipment.

[0131] For specific limitations on each step, please refer to the limitations on the intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order requirements mentioned above, which will not be repeated here.

[0132] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program being implemented when executed by a processor:

[0133] Step 1: Obtain order information, automatically calculate the geometric characteristic parameters of the beam to be precast, retrieve the material parameters of the beam to be precast, and determine the target curing temperature, target strength, and batch tensioning time according to the delivery schedule; the target strength includes the initial tensile strength of the concrete. Concrete design strength ;

[0134] Step 2: Monitor concrete temperature and ambient temperature in real time, and dynamically predict the real-time evolution data of current concrete strength based on concrete maturity theory.

[0135] Step 3: With the goal of minimizing total cost, the optimal steam curing time and corresponding optimal production parameters are dynamically calculated while satisfying the preset concrete strength constraints, and an execution command is issued to the tensioning equipment.

[0136] For specific limitations on each step, please refer to the limitations on the intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order requirements mentioned above, which will not be repeated here.

[0137] In summary, this invention, through real-time dynamic optimization, effectively solves the problems of high energy consumption for steam curing, long production cycles due to reliance on experience for tensioning timing, and low turnover rate of precast platforms in traditional precasting methods, while ensuring that the strength of concrete beams meets the standards. It achieves energy-saving, carbon-reducing, intelligent, and efficient precast production.

[0138] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention without departing from its spirit and scope should be included within the protection scope of the present invention.

Claims

1. A smart prefabrication method for energy-saving and carbon-reducing concrete beams based on order requirements, characterized in that, The method, through an algorithm model embedded in an intelligent platform, dynamically determines the optimal production parameters based on order demand. These optimal production parameters include the optimal tensioning time and tensioning control values ​​for batch tensioning. The method includes the following steps: Step 1: Obtain order information, automatically calculate the geometric characteristic parameters of the beam to be precast, retrieve the material parameters of the beam to be precast, and determine the target curing temperature, target strength, and batch tensioning time according to the delivery schedule; the target strength includes the initial tensile strength of the concrete. Concrete design strength ; Step 2: Monitor concrete temperature and ambient temperature in real time, and dynamically predict the real-time evolution data of current concrete strength based on concrete maturity theory. Step 3: With the goal of minimizing total cost, the optimal steam curing time and corresponding optimal production parameters are dynamically calculated while satisfying the preset concrete strength constraints, and an execution command is issued to the tensioning equipment.

2. The intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order demand according to claim 1, characterized in that, In step 1, the geometric feature parameters include the mass m and surface area A of the beam to be precast; the material parameters include the specific heat capacity c and heat transfer coefficient U of concrete; and the order information includes the delivery time, beam specifications, material parameters, and prestressing parameters.

3. The intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order demand according to claim 1, characterized in that, In step 2, the concrete strength is predicted using the concrete maturity-strength relationship curve; wherein, the concrete maturity-strength relationship curve is expressed as: In the formula, Indicates concrete strength; represents the ultimate strength of concrete; k represents the strength growth coefficient, which is a constant; t represents the steam curing time. The maturity of concrete is expressed as: In the formula, For real-time monitoring of concrete temperature, To monitor the ambient temperature in real time, This is the total time of hydration heat time and steam curing time t during the early age of concrete.

4. The intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order demand according to claim 1, characterized in that, In step 3, it is necessary to monitor in real time whether the current concrete strength meets the following conditions: If satisfied, the total energy consumption at the current moment is calculated immediately. and total cost ; In the formula, The current concrete strength. This refers to the initial tensile strength of the concrete.

5. The intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order requirements according to claim 4, characterized in that, In step 3, the expression for the total cost is: In the formula, For total cost, For energy consumption costs, Operating costs.

6. The intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order requirements according to claim 5, characterized in that, The energy consumption cost The calculation formula is as follows: In the formula, For energy unit price, Total energy consumption; The operating costs The calculation formula is as follows: In the formula, To set a fixed start-up cost, t represents the steam curing time. Let r be the time constant and r be the equipment operating cost rate.

7. The intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order demand according to claim 6, characterized in that, The total energy consumption The calculation formula is: in, The energy consumption for heating and steam curing is expressed as: To maintain the energy consumption during the phase, it is expressed as: In the formula, c is the specific heat capacity of concrete, and m is the mass of the concrete beam. The target curing temperature for concrete. The ambient temperature changes over time. The overall system efficiency coefficient is, and >1; U is the comprehensive heat transfer coefficient of the curing shed and template, and A is the heat dissipation surface area of ​​the protective structure.

8. The intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order requirements according to claim 5, characterized in that, In step 3, the optimal steam curing time The solution is as follows: If detected This shortens the optimal steam curing time. ; like Then extend the optimal steam curing time. ; like ,but .

9. The intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order demand according to claim 8, characterized in that, Step 3, issuing the execution command specifically includes: Initial tensioning: when the optimal steam curing time is reached. And satisfy Then, a "first tensioning" command is sent to the tensioning equipment; Secondary tensioning: After the first tensioning is completed, the beam is moved, and natural curing is used to allow the concrete strength to reach 100% of the concrete design strength. Then, a second tensioning is performed to establish the final prestress.

10. The intelligent prefabrication method for energy-saving and carbon-reducing concrete beams based on order demand according to claim 9, characterized in that, The formula for calculating the tension control force F during the initial tensioning is based on a mechanical equilibrium model: in, , , , ; In the formula, G is the self-weight of the precast concrete structure. Where is the prestressed steel strand rotation angle, h is the distance from the anchor point of the steel strand to the centroid of the section, and L is the length of the concrete structure. D is the distance between the bending point of the steel strand and the beam end, and D is the distance between the straight point of the steel strand and the beam end. Turning radius of steel strands.

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