Carbon emission measuring and calculating method and system for fabricated bridge construction

Abstract

The invention discloses a carbon emission measurement and calculation method and system for prefabricated bridge construction, relates to the technical field of green construction and engineering management, and aims to solve the problems of fragmentation of carbon emission measurement and calculation data, non-uniform models, poor process control real-time performance, weak decision support capability and the like in the prior art. A standardized, full-chain and digital solution is provided. The method comprises the following six steps: building a BIM model and extracting data, calculating carbon emission in prefabricated part production, calculating carbon emission in a transportation stage, calculating carbon emission in a field installation stage, summarizing carbon emission in a construction stage, and generating a standardized carbon emission report. The method has the beneficial effects that accurate, comparable and traceable measurement and calculation of the carbon emission in the construction stage of the fabricated bridge are realized; carbon hot spot recognition and low-carbon optimization decision making in the construction process are supported; and the refining level of engineering carbon management is remarkably improved, and systematic technical support is provided for green low-carbon construction of the fabricated bridge.

Description

Technical Field

[0001] This invention relates to the field of green construction and engineering management technology, specifically a method and system for calculating carbon emissions in prefabricated bridge construction. Background Technology

[0002] Prefabricated bridges, as an important development direction in modern bridge engineering, are widely used globally due to their advantages such as fast construction speed, controllable quality, and minimal environmental impact. Traditional cast-in-place bridge construction methods suffer from problems such as long on-site operation time, significant environmental impact, and difficulty in quality control. In contrast, prefabricated bridges, through factory prefabrication and on-site assembly, significantly improve construction efficiency and project quality.

[0003] Although prefabricated bridges have inherent advantages in energy conservation and emission reduction, the accurate quantification of their carbon emissions still faces the following technical challenges in practical engineering applications: (1) Data collection fragmentation problem: existing carbon emission calculation methods rely on manual statistics and splicing of data from multiple systems, resulting in: material usage data being manually extracted from design drawings, which has errors and lags; transportation data relying on drivers' handwritten records, which makes it difficult to guarantee authenticity and accuracy; construction machinery energy consumption data being missing or incomplete; and data from each link being isolated, making it impossible to form a complete data chain. (2) The standardization of calculation models is insufficient. The industry currently lacks unified calculation standards and methods, which are manifested in the following ways: the selection of emission factors is chaotic, different projects use factors from different sources, and the results are not comparable; the system boundaries are not unified, some include upstream production of building materials, while others only consider on-site emissions; the calculation methods vary greatly, some use the empirical coefficient method, while others use the detailed calculation method; there is a lack of special calculation models for the special processes of prefabricated bridges (such as component transportation and on-site hoisting). (3) The process control is not real-time. Traditional calculation methods are mostly post-event calculations, which cannot achieve: real-time monitoring of carbon emissions during construction; early warning of carbon emissions exceeding standards; dynamic optimization of construction schemes based on carbon emissions; and immediate effect evaluation of low-carbon construction measures. (4) The decision support capability is weak. The calculation results generated by the existing methods are in a single form and it is difficult to: accurately identify the key links of carbon emissions (carbon hotspots); quantitatively compare the carbon emission differences of different design schemes and construction schemes; provide data support for low-carbon procurement, low-carbon transportation and low-carbon construction; and meet the new management needs of green finance, carbon trading and other new management needs. Existing building carbon emission calculation software and methods have the following limitations: they focus mainly on the building sector, do not adequately consider the special characteristics of bridge engineering, lack coverage of the entire chain of prefabricated construction, fail to fully utilize digital technologies such as BIM and the Internet of Things, and have limited accuracy in calculation results, making it difficult to guide engineering practice. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for calculating carbon emissions in prefabricated bridge construction, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: The method for calculating carbon emissions from prefabricated bridge construction includes the following steps: Step 1: Establish BIM model and extract data; Step 2: Calculation of carbon emissions from prefabricated component production; Step 3: Calculation of carbon emissions during the transportation phase; Step 4: Carbon emission calculation during on-site installation; Step 5: Summary of carbon emissions during the construction phase; Step 6: Generate a standardized carbon emission report.

[0006] Preferably, step one involves using professional BIM software such as Revit or Tekla to construct a precise 3D model of the prefabricated bridge. The model created in this process has strict requirements; it must comprehensively cover all the complete attribute information of all prefabricated components. These complete attributes include many aspects, such as the component's geometric dimensions, including precise values ​​for length, width, height, and various complex shapes; material specifications, such as concrete strength grades (e.g., C30, C40, etc.) and rebar types (rebars of different diameters and materials); component numbers for accurate identification and management; and weight parameters, which are crucial for subsequent transportation and installation. Furthermore, a material usage list needs to be extracted from this carefully constructed BIM model, providing fundamental data support for the project's material management.

[0007] Preferably, it's worth reiterating the requirements for model attributes: the model must contain complete attributes of all precast components. These attributes are quite comprehensive, including geometric dimensions, a key element in determining the component's position and size in space. Whether a simple rectangular component or a complex irregular shape, its geometric dimensions must be accurate. Regarding material specifications, for concrete, its strength grade is a crucial indicator of its load-bearing capacity; different strength grades correspond to different mix proportions and performance characteristics. For steel reinforcement, the type involves the thickness, material, and other characteristics of the steel bars; different types of steel bars differ in their mechanical properties. Component numbers are unique identifiers for each component, facilitating tracking and management throughout the project lifecycle. Weight parameters are also an important attribute, relating to practical issues such as the selection of transportation methods and hoisting equipment.

[0008] Preferably, when proceeding to step two, the main focus is on determining the production energy consumption of each prefabricated component. In this step, standard emission factors are used to calculate the carbon emissions generated during the production phase. Determining production energy consumption is a complex process involving numerous production procedures and energy consumption types. By using standard emission factors, the carbon emissions during the production of these prefabricated components can be estimated relatively accurately, thus providing crucial data for the environmental assessment of the entire project.

[0009] Preferably, step three mainly involves recording detailed transportation information for each prefabricated component. Since various types of vehicles are involved in transportation, carbon emissions calculations need to be performed by vehicle type. Different vehicle types differ in fuel consumption, emission standards, etc. Therefore, this categorized calculation method can more accurately determine the carbon emissions generated during transportation, thus providing effective reference data for optimizing transportation plans and reducing overall carbon emissions.

[0010] Preferably, step four involves recording relevant information about the main construction machinery, including its model, operating hours, and energy consumption type. On construction sites, various pieces of machinery play an irreplaceable role, and their operation inevitably involves energy consumption and carbon emissions. To accurately calculate carbon emissions during the on-site installation phase, calculations need to be performed according to equipment classification. This allows for a clear understanding of the environmental impact of each type of equipment during installation, enabling targeted measures to reduce carbon emissions.

[0011] Preferably, step five involves summarizing the calculation results obtained from the previous three stages. During this summarization process, analysis needs to be performed along different dimensions, including stages (production, transportation, and installation), materials (carbon emissions of different materials such as concrete and steel reinforcement), and locations (carbon emission distribution of different components of the bridge, such as piers and bridge decks). This multi-dimensional analysis provides a comprehensive and in-depth understanding of the carbon emission status of the entire prefabricated bridge project, offering strong support for developing emission reduction strategies and optimizing project management.

[0012] Preferably, in step six, the specific content includes meticulously preparing a report according to the format specified in the "Standard for Calculation of Carbon Emissions in Buildings" (GB / T 51366). This report needs to include many key elements, among which various data tables are indispensable. These tables list in detail the basic data related to carbon emissions. At the same time, it should present the calculation process completely. This process should be clear and concise, and the logic of each step of the calculation should be presented in a well-organized manner. In addition, it needs to include an in-depth results analysis section, which analyzes and interprets the calculated carbon emission results from multiple angles and levels to comprehensively assess the carbon emission situation during the construction of prefabricated bridges.

[0013] The carbon emission calculation system for prefabricated bridge construction is a specially designed comprehensive system architecture. This system mainly consists of several core components: a memory, a host computer, and a computer program stored in the memory and capable of running on the host computer. The memory stores various important information, including raw data, intermediate calculation results, and the final carbon emission calculation results. The host computer is the core hardware platform for the entire system, providing robust hardware support for all operations. The computer program stored in the memory is the soul of the system's functionality. This specially configured program can accurately execute each step of the carbon emission calculation method for prefabricated bridge construction, ensuring the efficient and accurate completion of the entire carbon emission calculation process.

[0014] Compared with the prior art, the beneficial effects of the present invention are: (1) This invention establishes a calculation system covering the entire process from prefabrication to logistics and transportation and then to on-site installation through six standardized steps: material data is directly extracted from BIM model with an accuracy of over 99%, transportation and construction data are collected in real time by integrating the Internet of Things, and emission factors of national standard are uniformly adopted to ensure the accuracy and reliability of the calculation results. (2) Standardization and repeatability: Establish a unified system boundary and calculation method, provide standardized data collection templates, formulate detailed implementation procedures and quality control requirements, and ensure that the calculation results of different projects and at different times are comparable; (3) Digitalization and Automation: Realize the automatic extraction of BIM model data, support the automatic data collection of IoT devices, develop automated calculation programs, reduce manual intervention, and generate standardized report formats; (4) Improve the level of refined management of the project, quantitatively assess the carbon emission contribution of each construction link, accurately identify key control points of carbon emission, support the formulation of targeted emission reduction measures, and achieve process control and target management of carbon emission. Detailed Implementation

[0015] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] The present invention mainly includes the following steps: Step 1: Establishing the BIM model and extracting data Operation details: 1. Utilize professional BIM software such as Revit and Tekla to construct high-precision 3D models of prefabricated bridges, ensuring that the models accurately reflect the actual structure and assembly details of the bridges.

[0017] 2. The established model needs to comprehensively include detailed attribute information of all precast components. These attributes cover geometric dimensions, material specifications (such as the strength grade of concrete and the specific type of steel reinforcement), unique serial number of each component, and weight parameters, etc., in order to provide detailed data support for subsequent design, production and construction.

[0018] 3. Extract the material usage list from the completed BIM model. This list will summarize the usage of various materials, laying a solid foundation for cost accounting, material procurement, and construction organization planning.

[0019] Calculation formula: For the i-th component, its material usage is: in The amount of material j used in component i, in kilograms (kg), is calculated. The volume of component i is in cubic meters (m³), which can be obtained directly from the BIM model; In addition, the density of material j, measured in kilograms per cubic meter (kg / m³), is also a known parameter and plays a crucial role in the calculation process. These factors are interrelated and together constitute the basic system for calculating the amount of material used.

[0020] Output: Total material usage list: Step 2: Calculation of carbon emissions from prefabricated component production.

[0021] Operation details: 1. Determine the production energy consumption for each precast component; 2. Calculate carbon emissions during the production phase using standard emission factors; Calculation formula: in The total carbon emissions during the production phase are measured in kilograms of carbon dioxide equivalent (kg CO2e). The total amount of material j is expressed in kilograms (kg), and this data comes from the detailed statistics and calculation results in step 1; The carbon emission factor of material j represents the carbon emissions generated per kilogram of the material, expressed in kilograms of carbon dioxide equivalent per kilogram (kg CO2e / kg). The value is determined according to national standards to ensure the authority and accuracy of the data. The total electricity consumed by the prefabrication plant during the production process is measured in kilowatt-hours (kWh). This data comes directly from the actual records of the electricity meters, thus ensuring the authenticity and reliability of the data. The emission factor of a regional power grid represents the carbon emissions corresponding to each kilowatt-hour of electricity consumed, expressed in kilograms of carbon dioxide equivalent per kilowatt-hour (kg CO2e / kWh). The value is based on the latest relevant data released by the state to reflect the carbon emission level under the current power production structure.

[0022] Fixed parameters (example values; actual values ​​should conform to national standards): Concrete emission factors: Reinforcing steel discharge factor: Regional power grid factors: (Taking the East China Power Grid as an example).

[0023] Step 3: Carbon emission calculation during the transportation phase Operational procedures: In this step, detailed transportation information for each prefabricated component needs to be recorded, including but not limited to the origin, destination, route, and type of transport vehicle used. Based on this, carbon emissions during transportation are calculated and categorized according to different vehicle types to ensure data accuracy and traceability. The key to this step is to comprehensively collect basic transportation data and rationally select calculation parameters based on actual transportation conditions to accurately assess the carbon emissions generated during the transportation phase. The calculation formula is as follows: Total carbon emissions during the transportation phase (in kg CO2e) This is calculated by summing the carbon emissions of each vehicle type during each transport trip. The transport distance for the k-th trip is represented by (in km), which refers to the actual mileage traveled by the vehicle from its origin to its destination. Simultaneously, the carbon emission factor for different vehicle types, i.e., the CO2 equivalent generated per kilometer of transport, must be considered. Multiplying this factor by the transport distance and summing the results yields the total carbon emissions for the transport phase. The application of this formula needs to be flexibly adjusted according to actual circumstances to ensure the accuracy and reliability of the calculation results.

[0024] From shipping document records; The weight (t) of the cargo in the kth train is from the loading record; : Emission factor of the vehicle type used in train k (kg CO2e / (t·km)).

[0025] Fixed parameters (based on the "Road Vehicle Carbon Emission Accounting Standard"): Heavy-duty diesel truck (30t load capacity): Medium-sized diesel truck (10t load capacity): Step 4: Carbon emission calculation during on-site installation Operation content: Record the model, working time, and energy consumption type of the main construction machinery, and calculate the carbon emissions of on-site installation according to equipment category.

[0026] Calculation formula: in: Total carbon emissions from on-site installation (kg CO2e); The working time (h) of the p-th type of construction equipment is from the equipment operation record; The average power or fuel consumption (L / h or kg / h) of the p-th type of equipment is based on the parameters on the equipment nameplate. : Emission factor of the fuel used by the p-th type of equipment (kg CO2e / L or kg CO2e / kg).

[0027] Fixed parameters (based on IPCC emission factors): diesel fuel: gasoline: Electricity: Use (Same as step 2).

[0028] Step 5: Summary of carbon emissions during the construction phase Operation details: The calculation results from the three stages are summarized and analyzed by stage, material, and location. Calculation formula: Total carbon emissions: Percentage of each stage: Contributions from each material: Step Six: Generate a standardized carbon emission report The operation details are as follows: A comprehensive carbon emissions report should be meticulously prepared in accordance with the format requirements stipulated in the "Standard for Calculation of Building Carbon Emissions" (GB / T 51366). This report needs to comprehensively and meticulously cover several key elements, including essential data tables that accurately present the basic data and statistical results related to carbon emissions. Simultaneously, the report must fully demonstrate the entire calculation process, from the initial data collection and processing to the step-by-step derivation using appropriate calculation methods and formulas, clearly explaining how carbon emissions are calculated. Furthermore, an in-depth analysis of the final calculation results is required, including assessing the reasonableness of the results, exploring potential sources of error, and understanding the underlying building carbon emissions situation and potential areas for improvement. This comprehensive report preparation ensures that the report meets standardized requirements in both form and content.

[0029] The mandatory reporting requirements are as follows: The cover page should include basic project information, providing a basic introduction and explanation of the project. It should also indicate the units of measurement, which helps readers understand how the data in the report is measured. The calculation date is also essential, indicating the timeframe of the report.

[0030] The abstract should cover the total carbon emissions, providing an overall overview of the project's carbon emissions. Additionally, it should include unit metrics, specifically kilograms of CO2 equivalent per square meter of bridge deck area (kg CO2e / m² bridge deck area). This metric allows readers to more intuitively understand the carbon emissions per unit bridge deck area.

[0031] The calculation process includes an input data table, which details all the initial data used in the calculation. There is also an emission factor table, which is a crucial parameter for calculating carbon emissions and is presented in a table for easy reference and verification. Furthermore, a detailed calculation table is also an important component, providing a complete overview of the entire calculation process, including the data calculations involved in each step.

[0032] The results analysis section includes a pie chart showing the contribution of different stages to carbon emissions. This chart clearly illustrates the proportional relationship between the contributions of different stages. Additionally, a bar chart showing the material contribution is also important, displaying the contribution of different materials to carbon emissions in a bar chart format, making the results more intuitive and easier to understand.

[0033] The data quality statement section should explain the data sources, clearly indicating where the data used in the report was obtained, which helps improve the report's credibility. It should also include an uncertainty analysis, dissecting potential errors or uncertainties in the data to give readers a more comprehensive understanding of the data quality.

[0034] The appendix contains original data records, which are retained for subsequent verification and traceability. Additionally, proof of the emission factor sources is required, which demonstrates the reliability and authority of the emission factors and further enhances the report's persuasiveness.

[0035] Key points for plan implementation: 1. Data collection requirements: All measuring equipment used, including electricity meters, flow meters, and GPS positioning devices, must be strictly guaranteed to be within their calibration validity period to ensure the accuracy and legality of data collection. Simultaneously, all original records must be properly preserved for at least three years to facilitate subsequent verification and traceability. Furthermore, when selecting emission factors, the latest figures published by the relevant national or provincial authorities should be used to ensure the authority and timeliness of the calculation results.

[0036] 2. Quality control measures: Throughout the carbon emission calculation process, to improve the accuracy of the results, all calculations must be completed independently by two staff members, and then cross-checked to reduce human error. Any changes to key parameters must be meticulously documented, detailing the reasons for the changes and the corresponding approval process, ensuring traceability. Furthermore, existing calculation methods are comprehensively reviewed and updated annually to adapt to evolving needs and technological advancements.

[0037] 3. Scope of application: This scheme is primarily applicable to carbon emission calculations for various types of prefabricated highway bridges, railway bridges, and municipal bridges. However, it's important to note that this scheme does not cover carbon emissions generated during the bridge's operation and demolition phases. For bridges with special structural forms, such as cable-stayed bridges and suspension bridges, additional specialized calculation items are required to more accurately reflect their carbon emission characteristics.

[0038] This solution, through the aforementioned six steps, constructs a complete closed-loop system from data collection to report generation, effectively ensuring the accuracy, comparability, and traceability of carbon emission calculations for prefabricated bridge construction. This series of rigorous process designs and quality control measures provides strong technical support for promoting the green and low-carbon development of my country's construction industry.

[0039] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0040] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for calculating carbon emissions from prefabricated bridge construction, characterized in that, Includes the following steps: Step 1: Establish BIM model and extract data; Step 2: Calculation of carbon emissions from prefabricated component production; Step 3: Calculation of carbon emissions during the transportation phase; Step 4: Carbon emission calculation during on-site installation; Step 5: Summary of carbon emissions during the construction phase; Step 6: Generate a standardized carbon emission report.

2. The carbon emission calculation method for prefabricated bridge construction according to claim 1, characterized in that, Step one involves using BIM software such as Revit and Tekla to create an accurate 3D model of the prefabricated bridge. The model must contain the complete attributes of all prefabricated components, and the material usage list must be extracted from the BIM model.

3. The carbon emission calculation method for prefabricated bridge construction according to claim 2, characterized in that, The model must contain complete properties of all precast components, including geometric dimensions, material specifications (concrete strength grade, steel reinforcement type), component number, and weight parameters.

4. The carbon emission calculation method for prefabricated bridge construction according to claim 1, characterized in that, Step two involves determining the production energy consumption of each prefabricated component and calculating carbon emissions during the production phase using standard emission factors.

5. The carbon emission calculation method for prefabricated bridge construction according to claim 1, characterized in that, Step three involves recording the transportation information for each prefabricated component and calculating transportation carbon emissions by vehicle type.

6. The carbon emission calculation method for prefabricated bridge construction according to claim 1, characterized in that, Step four involves recording the model, working time, and energy consumption type of the main construction machinery, and calculating the carbon emissions from on-site installation according to equipment category.

7. The carbon emission calculation method for prefabricated bridge construction according to claim 1, characterized in that, Step five involves summarizing the calculation results from the three stages and performing a breakdown analysis by stage, material, and location.

8. The carbon emission calculation method for prefabricated bridge construction according to claim 1, characterized in that, Step six involves preparing a report in accordance with the format of the "Building Carbon Emission Calculation Standard" (GB / T 51366), including necessary data tables, calculation process, and result analysis.

9. A carbon emission calculation system for prefabricated bridge construction, characterized in that, include: The computer includes a memory, a host computer, and a computer program stored in the memory and executable on the host computer, the computer program being configured to implement the steps of the carbon emission calculation method for prefabricated bridge construction as described in any one of claims 1 to 8.

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