In the context of global emission reduction, the low-carbon sustainable development of the construction industry has become an important research content. With the vigorous development of new industrial technologies, ...In the context of global emission reduction, the low-carbon sustainable development of the construction industry has become an important research content. With the vigorous development of new industrial technologies, the application of prefabrication technology to buildings had become a mainstream. However, the research on the role of prefabricated technology in reducing building carbon emissions was not yet comprehensive, and the research on the relationship between prefabricated structure types and carbon emissions in the construction stage was not yet thorough. Guided by life cycle assessment (LCA), this paper used the scenario analysis method to set different working conditions for five different structural systems, and used SimaPro software to evaluate the carbon emissions of prefabricated buildings in order to clarify the carbon emissions of prefabricated buildings under different structural systems, and explore their impact mechanisms in depth. Finally, take the existing buildings in China as an empirical study, the results showed that: 1) The carbon emissions produced by the four common prefabricated structural systems were almost the same. Different structures had different requirements for the combination of components. The carbon emissions of individual buildings would be superimposed according to the carbon emission characteristics of various individual components to form the final total carbon emissions. 2) When the building structure system requires more combinations of components, the greater the amount of transportation invested in the transportation process, the more carbon emissions would be caused. In the calculation of all individual building construction stages, the carbon emissions generated by tower cranes almost exceed the sum of the carbon emissions of all mobile machinery. 3) Prefabricated shear wall structures and prefabricated frame-shear wall structures require a large amount of hoisting of prefabricated shear walls, so the carbon emissions of their mechanical equipment were also the highest.展开更多
The measurement and calculation of the carbon emission from the production of prefabricated building components were studied.Based on the carbon emission factor method,a carbon emission calculation model of the compon...The measurement and calculation of the carbon emission from the production of prefabricated building components were studied.Based on the carbon emission factor method,a carbon emission calculation model of the components in the production phase was established.Besides,the actual measurement method and calculated at rated power method were proposed for the measurement and calculation of carbon emission,and several measurements were carried out in a component factory located in a coastal area of south China and a component factory located in Beijing,respectively.The results of the study show that the carbon emission factors of laminates and wallboards produced by factories located in coastal areas of southern China under natural curing conditions were 7.61 kg CO2/m3 and 5.84 kg CO2/m3 respectively.The carbon emissions conversion coefficients of concrete mixer,reinforcing bar production line and travelling crane between actual operation and with per the rated power were approximately 0.44,0.34 and 0.34 respectively.When the actual measurement cannot be performed,the conversion coefficient can be used to correct the data of the calculated at rated power to make it closer to the true value.The carbon emission factor of the laminated panels produced by the component factory in Beijing under steam curing concrete conditions was 132.15 kg CO2/m3,and the factory is used as a prototype,a complementary steam generation system model of solar energy and boiler was established,and it was calculated that the system can reduce CO2 emissions by about 300 tons throughout the year.展开更多
Prefabricated engineered solid wood panel construction systems can sequester and store CO_(2).Modular cross-laminated timber(CLT,also called cross-lam)panels form the basis of low-carbon,engineered construction system...Prefabricated engineered solid wood panel construction systems can sequester and store CO_(2).Modular cross-laminated timber(CLT,also called cross-lam)panels form the basis of low-carbon,engineered construction systems using solid wood panels that can be used to build residential infill developments of 10 storeys or higher.Multi-apartment buildings of 4 to 10 storeys constructed entirely in timber,such as recently in Europe,are innovative,but their social and cultural acceptance in Australia and North America is at this stage still uncertain.Commercial utilisation is only possible if there is a demand and user acceptance.This paper explores the opportunities offered by an innovative low carbon construction system using cross-laminated timber(CLT)panels to improve the design and delivery of urban infill housing.CLT construction has been developed around 1996 in Austria:layers of timber boards are glued crosswise in different directions to increase loadbearing capacity.The paper describes a multi-disciplinary research project into cross-laminated timber panels which aims to transform the Australian construction and development industry,involving a range of key partners.This project will introduce cross-laminated timber panels as a way to build with a lightweight prefabricated low-carbon construction system that is advantageous for urban infill and residential buildings in the range of 4 to 8 stories height.The challenges,research questions and advantages of this new engineered timber system are explained,and a detailed research methodology for further research is presented.展开更多
Understanding global carbon cycle is critical to uncover the mechanisms of global warming and remediate its adverse ef fects on human activities.Organic carbon in marine sediments is an indispensable part of the globa...Understanding global carbon cycle is critical to uncover the mechanisms of global warming and remediate its adverse ef fects on human activities.Organic carbon in marine sediments is an indispensable part of the global carbon reservoir in global carbon cycling.Evaluating such a reservoir calls for quantitative studies of marine carbon burial,which closely depend on quantifying total organic carbon and black carbon in marine sediment cores and subsequently on obtaining their high-resolution temporal sequences.However,the conventional methods for detecting the contents of total organic carbon or black carbon cannot resolve the following specific difficulties,i.e.,(1)a very limited amount of each subsample versus the diverse analytical items,(2) a low and fluctuating recovery rate of total organic carbon or black carbon versus the reproducibility of carbon data,and(3)a large number of subsamples versus the rapid batch measurements.In this work,(i)adopting the customized disposable ceramic crucibles with the microporecontrolled ability,(ii)developing self-made or customized facilities for the procedures of acidification and chemothermal oxidization,and(iii)optimizing procedures and carbon-sulfur analyzer,we have built a novel Wang-Xu-Yuan method(the WXY method)for measuring the contents of total organic carbon or black carbon in marine sediment cores,which includes the procedures of pretreatment,weighing,acidification,chemothermal oxidation and quantification;and can fully meet the requirements of establishing their highresolution temporal sequences,whatever in the recovery,experimental efficiency,accuracy and reliability of the measurements,and homogeneity of samples.In particular,the usage of disposable ceramic crucibles leads to evidently simplify the experimental scenario,which further results in the very high recovery rates for total organic carbon and black carbon.This new technique may provide a significant support for revealing the mechanism of carbon burial and evaluating the capacity of marine carbon accumulation and sequestration.展开更多
文摘In the context of global emission reduction, the low-carbon sustainable development of the construction industry has become an important research content. With the vigorous development of new industrial technologies, the application of prefabrication technology to buildings had become a mainstream. However, the research on the role of prefabricated technology in reducing building carbon emissions was not yet comprehensive, and the research on the relationship between prefabricated structure types and carbon emissions in the construction stage was not yet thorough. Guided by life cycle assessment (LCA), this paper used the scenario analysis method to set different working conditions for five different structural systems, and used SimaPro software to evaluate the carbon emissions of prefabricated buildings in order to clarify the carbon emissions of prefabricated buildings under different structural systems, and explore their impact mechanisms in depth. Finally, take the existing buildings in China as an empirical study, the results showed that: 1) The carbon emissions produced by the four common prefabricated structural systems were almost the same. Different structures had different requirements for the combination of components. The carbon emissions of individual buildings would be superimposed according to the carbon emission characteristics of various individual components to form the final total carbon emissions. 2) When the building structure system requires more combinations of components, the greater the amount of transportation invested in the transportation process, the more carbon emissions would be caused. In the calculation of all individual building construction stages, the carbon emissions generated by tower cranes almost exceed the sum of the carbon emissions of all mobile machinery. 3) Prefabricated shear wall structures and prefabricated frame-shear wall structures require a large amount of hoisting of prefabricated shear walls, so the carbon emissions of their mechanical equipment were also the highest.
基金This work was financially supported by National Key R&D Plan(2016YFC0701807).
文摘The measurement and calculation of the carbon emission from the production of prefabricated building components were studied.Based on the carbon emission factor method,a carbon emission calculation model of the components in the production phase was established.Besides,the actual measurement method and calculated at rated power method were proposed for the measurement and calculation of carbon emission,and several measurements were carried out in a component factory located in a coastal area of south China and a component factory located in Beijing,respectively.The results of the study show that the carbon emission factors of laminates and wallboards produced by factories located in coastal areas of southern China under natural curing conditions were 7.61 kg CO2/m3 and 5.84 kg CO2/m3 respectively.The carbon emissions conversion coefficients of concrete mixer,reinforcing bar production line and travelling crane between actual operation and with per the rated power were approximately 0.44,0.34 and 0.34 respectively.When the actual measurement cannot be performed,the conversion coefficient can be used to correct the data of the calculated at rated power to make it closer to the true value.The carbon emission factor of the laminated panels produced by the component factory in Beijing under steam curing concrete conditions was 132.15 kg CO2/m3,and the factory is used as a prototype,a complementary steam generation system model of solar energy and boiler was established,and it was calculated that the system can reduce CO2 emissions by about 300 tons throughout the year.
基金Supported by the National Natural Science Foundation （51208268）the Pubiic-Welfare-Technology Research Industry Project of Science Technology Department of Zhejiang （2011 C21078） the Social Development Project of Science Technology Bureau of Ningbo （2011CS0017）.
文摘Prefabricated engineered solid wood panel construction systems can sequester and store CO_(2).Modular cross-laminated timber(CLT,also called cross-lam)panels form the basis of low-carbon,engineered construction systems using solid wood panels that can be used to build residential infill developments of 10 storeys or higher.Multi-apartment buildings of 4 to 10 storeys constructed entirely in timber,such as recently in Europe,are innovative,but their social and cultural acceptance in Australia and North America is at this stage still uncertain.Commercial utilisation is only possible if there is a demand and user acceptance.This paper explores the opportunities offered by an innovative low carbon construction system using cross-laminated timber(CLT)panels to improve the design and delivery of urban infill housing.CLT construction has been developed around 1996 in Austria:layers of timber boards are glued crosswise in different directions to increase loadbearing capacity.The paper describes a multi-disciplinary research project into cross-laminated timber panels which aims to transform the Australian construction and development industry,involving a range of key partners.This project will introduce cross-laminated timber panels as a way to build with a lightweight prefabricated low-carbon construction system that is advantageous for urban infill and residential buildings in the range of 4 to 8 stories height.The challenges,research questions and advantages of this new engineered timber system are explained,and a detailed research methodology for further research is presented.
基金Supported by the National Basic Research Program of China(973 Program)(No.2012CB956004)the Fundamental Research Funds for the Central Universities(No.16lgjc22)
文摘Understanding global carbon cycle is critical to uncover the mechanisms of global warming and remediate its adverse ef fects on human activities.Organic carbon in marine sediments is an indispensable part of the global carbon reservoir in global carbon cycling.Evaluating such a reservoir calls for quantitative studies of marine carbon burial,which closely depend on quantifying total organic carbon and black carbon in marine sediment cores and subsequently on obtaining their high-resolution temporal sequences.However,the conventional methods for detecting the contents of total organic carbon or black carbon cannot resolve the following specific difficulties,i.e.,(1)a very limited amount of each subsample versus the diverse analytical items,(2) a low and fluctuating recovery rate of total organic carbon or black carbon versus the reproducibility of carbon data,and(3)a large number of subsamples versus the rapid batch measurements.In this work,(i)adopting the customized disposable ceramic crucibles with the microporecontrolled ability,(ii)developing self-made or customized facilities for the procedures of acidification and chemothermal oxidization,and(iii)optimizing procedures and carbon-sulfur analyzer,we have built a novel Wang-Xu-Yuan method(the WXY method)for measuring the contents of total organic carbon or black carbon in marine sediment cores,which includes the procedures of pretreatment,weighing,acidification,chemothermal oxidation and quantification;and can fully meet the requirements of establishing their highresolution temporal sequences,whatever in the recovery,experimental efficiency,accuracy and reliability of the measurements,and homogeneity of samples.In particular,the usage of disposable ceramic crucibles leads to evidently simplify the experimental scenario,which further results in the very high recovery rates for total organic carbon and black carbon.This new technique may provide a significant support for revealing the mechanism of carbon burial and evaluating the capacity of marine carbon accumulation and sequestration.
