西南农村地区现代夯土住宅物化阶段碳排放研究

Study on embodied carbon emissions of innovative rammed earth construction in rural areas of Southwest China

物化阶段CO_(2)排放时间较为集中且减排潜力巨大,因此对建筑物化阶段碳排放进行量化研究具有必要性。目前,我国农村住宅砖混结构仍为主流形式,制约了低碳农村的发展。为了阐述现代夯土建筑采用“本土材料、本土技术”的建造方式可有效节能减排。本研究在考虑现代夯土建筑建造方式的特殊性和建造过程中数据清单受人为统计水平限制导致结果出现差异性的基础上,提出将排放因子法结合不同结构形式的现代夯土建筑具体施工方式和广联达BIM算量软件对建筑物化阶段进行精确建模,分析不同结构形式的现代夯土建筑物化阶段碳排放变化情况。从环境可持续发展层面的碳排放角度,以现代夯土建筑和普通砖混结构农宅为例,构建适用于不同建筑结构物化阶段CO_(2)排放的计算模型,以量化出来的指标数据来评价前者的减排效果。计算得出,西南农村地区不同结构形式的现代夯土建筑在生产、运输阶段的单位面积碳排放量分别为177.63 kgCO_(2)e/m^(2)、264.7 kgCO_(2)e/m^(2),施工阶段的单位面积碳排放量分别为19.1kg CO_(2)e/m^(2)、15.94 kgCO_(2)e/m^(2);通过对比分析,不同结构形式现代夯土建筑建造阶段的单位面积碳排放量分别为196.73 kgCO_(2)e/m^(2)、280.64 kgCO_(2)e/m^(2)是传统砖混结构的1.7倍、1.2倍,此数据提供了现代夯土建筑可以节能减排的依据,也为西南农村地区的住宅建设提供绿色发展的新思路。

The materialization phase in the lifecycle of buildings,which involves the production and utilization of construction materials,is a critical period that sees concentrated CO_(2) emissions.This phase is significant because it offers substantial potential for emission reductions,making it imperative to conduct quantitative research on carbon emissions during this stage.In rural China,brick-concrete structures remain the predominant form of residential buildings.However,this widespread use of traditional construction methods hinders the advancement of low-carbon rural development.This study seeks to illustrate that modern rammed earth buildings,which leverage“local materials and local techniques”,can significantly enhance energy efficiency and reduce emissions.By focusing on the unique construction methods of modern rammed earth buildings,we can address potential discrepancies in data resulting from statistical limitations.This research combines the emission factor method with specific construction techniques of modern rammed earth buildings.Additionally,we utilize BIM software to precisely model the materialization phase,allowing us to analyze the variations in carbon emissions for different structural forms of these buildings.To begin with,it is important to understand the context and motivation behind this research.Traditional brick-concrete structures,while durable and widely accepted,have a considerable carbon footprint.The production of bricks and concrete involves energy-intensive processes that release significant amounts of CO_(2).Transporting these materials from production sites to construction locations further adds to their carbon emissions.In contrast,modern rammed earth buildings employ local materials,which are often more sustainable and have lower embodied energy.These buildings also utilize local construction techniques,reducing the need for energy-intensive machinery and transportation.The methodology adopted in this study involves a combination of the emission factor method and precise construction modeling using BIM software.The emission factor method helps in quantifying the emissions per unit of activity,such as per square meter of building area.By integrating this method with detailed construction data from BIM software,we can achieve a high level of accuracy in modeling the materialization phase of buildings.This approach allows us to analyze the carbon emissions associated with different structural forms of modern rammed earth buildings comprehensively.The findings of this study are significant.In the southwestern rural areas of China,the unit area carbon emissions during the production and transportation phases of modern rammed earth buildings are calculated to be 177.63 kg CO_(2)e/m^(2) and 264.7 kg CO_(2)e/m^(2),respectively.During the construction phase,the emissions are found to be 19.1 kg CO_(2)e/m^(2) and 15.94 kg CO_(2)e/m^(2),respectively.These figures highlight the substantial differences in emissions between modern rammed earth buildings and traditional brick-concrete structures.A comparative analysis reveals that the unit area carbon emissions during the construction phase for different structural forms of modern rammed earth buildings are 196.73 kg CO_(2)e/m^(2) and 280.64 kg CO_(2)e/m^(2).When compared to traditional brick-concrete structures,these figures are 1.7 times and 1.2 times higher,respectively.This data provides a basis for understanding the energy-saving and emission-reducing potential of modern rammed earth buildings.Despite the higher emissions during the construction phase,the overall environmental impact of these buildings is lower due to their sustainable materials and construction practices.The implications of these findings are profound.Modern rammed earth buildings offer a viable solution for promoting green development in rural residential construction.By adopting local materials and techniques,these buildings not only reduce their carbon footprint but also support local economies and traditions.The study underscores the importance of rethinking traditional construction methods and embracing more sustainable alternatives.Furthermore,this research provides a new perspective on the role of modern rammed earth buildings in achieving environmental sustainability.It highlights the need for policymakers and builders to consider the entire lifecycle of buildings,from material production to construction and beyond.By focusing on the materialization phase,significant strides can be made in reducing the overall carbon emissions of the construction industry.In conclusion,this study demonstrates that modern rammed earth buildings,through their use of local materials and techniques,can play a crucial role in reducing carbon emissions and promoting sustainable development in rural areas.The combination of the emission factor method and BIM software provides a robust framework for accurately modeling and analyzing carbon emissions during the materialization phase.As the construction industry continues to seek ways to minimize its environmental impact,the insights gained from this research offer valuable guidance for the adoption of more sustainable building practices.