不同结构建筑生命周期的碳排放比较

温室气体(GHG)的排放导致全球气候变暖已成为人类社会的共识。建筑业活动及相关产品产生大量的温室气体,为了定量分析建筑物GHG的排放情况,本文基于生命周期评价(LCA)理论,建立了建筑生命周期碳排放的核算模型。同时,为了探讨建筑业减排指标和减少建筑业碳排放的途径,本文选取木结构、轻钢结构和钢筋混凝土结构3种不同结构形式的建筑,对其生命周期碳排放进行了定量测算和对比分析。结果表明,在满足同样使用功能的前提下,木结构建筑相比其它2种结构的建筑具有较低的生命周期碳排放。     

建筑全生命周期碳排放量计算模型

建立建筑全生命周期碳排放量计算模型,定量研究生产、运输、建造、运行、拆除和回收不同阶段的碳排放量,并以上海某公共建筑为案例,进行了建筑全生命周期碳排放量的计算,结果表明,该建筑全生命周期单位面积碳排放量指标为2.72 t/m2,运行期间的建筑碳排放量在建筑全生命周期碳排放量占比最高,其次为建材生产阶段.降低运行阶段的能源需求,选择可再循环和碳排放因子小的建材、减少建筑材料的使用和浪费有助于降低建筑全生命周期碳排放量.该模型的建立,可为建筑全生命周期碳排放计算提供依据,为优化设计方案、建造方案和运行方案提供方法指导.     

建筑全生命周期碳排放量计算模型

建立建筑全生命周期碳排放量计算模型,定量研究生产、运输、建造、运行、拆除和回收不同阶段的碳排放量,并以上海某公共建筑为案例,进行了建筑全生命周期碳排放量的计算,结果表明,该建筑全生命周期单位面积碳排放量指标为2.72 t/m2,运行期间的建筑碳排放量在建筑全生命周期碳排放量占比最高,其次为建材生产阶段.降低运行阶段的能源需求,选择可再循环和碳排放因子小的建材、减少建筑材料的使用和浪费有助于降低建筑全生命周期碳排放量.该模型的建立,可为建筑全生命周期碳排放计算提供依据,为优化设计方案、建造方案和运行方案提供方法指导.     

建筑全生命周期碳排放量计算模型

建立建筑全生命周期碳排放量计算模型,定量研究生产、运输、建造、运行、拆除和回收不同阶段的碳排放量,并以上海某公共建筑为案例,进行了建筑全生命周期碳排放量的计算,结果表明,该建筑全生命周期单位面积碳排放量指标为2.72 t/m2,运行期间的建筑碳排放量在建筑全生命周期碳排放量占比最高,其次为建材生产阶段.降低运行阶段的能源需求,选择可再循环和碳排放因子小的建材、减少建筑材料的使用和浪费有助于降低建筑全生命周期碳排放量.该模型的建立,可为建筑全生命周期碳排放计算提供依据,为优化设计方案、建造方案和运行方案提供方法指导.     

绿色居住建筑全生命周期碳排放研究

建筑领域碳排放占全社会总能耗的1/3,这仅仅是建筑运行使用过程,若考虑建筑全生命周期,比例将会更高。在现行的绿色建筑评价标准引导下,绿色建筑是否比普通建筑全生命周期更低碳,目前相关研究甚少。本项研究基于LCA理论,在总结前人研究基础上,明确绿色建筑全生命周期碳排放计算方法,并以天津生态城75栋绿色居住建筑为样本,计算并比较了不同星级绿色居住建筑全生命周期碳排放水平。结果表明,单位建筑面积年碳排放量为43-64kg CO2/m2·a,且碳排放水平与绿色建筑星级无明显关系。本项研究为建立天津地区建筑全生命周期碳排放清单数据库和评价体系提供支撑。     

低碳建筑全生命周期碳排放影响因素分析

文章基于全生命周期评价理论,以住宅建筑为例,对低碳建筑概念进行界定,并且在整个建筑的全生命过程中,从建筑项目的决策、规划设计、施工、使用和拆除五个阶段分析低碳建筑各阶段影响碳排放的因素。     

零能耗太阳能住宅产品的建筑全生命周期碳排放分析

太阳能技术的引入在建筑使用阶段达到了低碳减排的目的,然而"低碳"不能依靠末端减排。作为一项系统工程,真正实现低碳建筑要靠系统减排。该文以"零能耗太阳能住宅产品"为例,通过核算建筑全生命周期(主要是建材开采、生产阶段和建筑使用阶段)的碳排放,客观、真实地反映太阳能光伏技术的应用对建筑全生命周期碳排放的影响。结论:由于使用太阳能系统,使用阶段的碳排放量降低了90%,然而太阳能系统在建材生产阶段的碳排放量也是不容忽视的,太阳能光电板生产的碳排放占总建材碳排放量的41%,必须纳入到建筑碳排放的全生命周期中去考虑。     

建造阶段碳排放量对建筑全生命周期碳排放量的影响分析

进入“十四五”时期,为达成“碳达峰”和“碳中和”的目标,国家和行业对工程建造阶段的碳排放研究提出了更高的要求。本文针对“建造阶段碳排放量对建筑全生命周期碳排放量的影响”这一行业内普遍关注的问题,从四个方面进行了剖析探讨,并针对相关国家规范实施的影响进行了分析。基于探讨和分析的结果,对工程承包企业在工程建造阶段的碳排放研究给出了建议。     

全生命周期理念下的建筑碳排放测算方法

目前,由于温室气体大量排放导致的全球变暖已成为全球关注的焦点问题,全生命周期理论与建筑信息模型技术的结合能够使碳排放测算更加具体、科学,有助于推动我国的低碳经济发展。本文基于建筑项目的全生命周期理论和BIM技术,详细探讨了建筑碳排放的测算方法,首先介绍了常见的测算方法,然后基于BIM技术建立建筑项目各阶段如设计规划、物化等阶段的碳排放测算模型,并结合某建筑工程进行测算,最后提出减少建筑碳排放量的策略,以供相关研究参考。     

既有居住建筑超低能耗节能改造全生命周期碳排放研究

通过对既有居住建筑超低能耗全生命周期各阶段进行分析,简化各阶段计算公式,结合示范项目测算碳排放量,确定了超低能耗节能改造后既有居住建筑碳排放量可节约57.95％,并显著减少温室气体排放,降低温室效应.     

基于全生命周期理论的住宅建筑能耗计算与分析

运用全生命周期理论,结合住宅建筑的自身特点,通过建立计算模型,对住宅建筑的能耗进行了计算与分析。找出了住宅建筑各能耗之间的内在关系,为建设节能型住宅提供相应的理论依据,以促进住宅建筑的可持续发展。     

Life cycle assessment of a Danish office building designed for disassembly

ABSTRACT

The building industry is responsible for a large proportion of anthropogenic environmental impacts. Circular economy (CE) is a restorative and regenerative industrial economic approach that promotes resource efficiency to reduce waste and environmental burdens. Transitioning from a linear approach to a CE within the building industry will be a significant challenge. However, an insufficient number of quantitative studies exist to confirm the potential (positive) environmental effects of CE within the built environment as well as a consistent method for characterizing these effects. This paper considers key methodological issues for quantifying the environmental implications of CE principles and proposes a life cycle assessment (LCA) allocation method to address these issues. The proposed method is applied to a case study of a Danish office building where the concrete structure is designed for disassembly (DfD) for subsequent reuse. The potential environmental impact savings vary between the different impact categories. The savings are significantly influenced by the building’s material composition, particularly the number of component-use cycles as well as the service life of the building and its components. The substitution of other material choices (e.g. glass and wood) for the concrete structure exhibited a potential increase in impact savings.     

Energy use, CO2 emissions and waste throughout the life cycle of a sample of hotels in the Balearic Islands

Tourism is the most developed economic sector in the Balearic Islands. The great rise in construction activities within the last 50 years, the increase in energy use, in CO₂ emissions and in waste production due to tourism, as well as an electrical energy production system mainly based on coal and fossil fuels is not an environmentally sustainable scenario. The aim of this study is to identify the processes that have had the greatest impact on the life cycle of a tourist building. In order to do this, the energy uses, CO₂ emissions and waste materials generated have been estimated, assuming a life cycle of 50 years, within a sample of hotels from the Balearic Islands. The results show that the operating phase, which represents between 70% and 80% of the total energy use, is the one with the greatest impact; that the energy use due to the manufacture of materials represents a fifth of the total and that electric consumption is the main cause of CO₂ emissions because of the regional energy system.     

A future bamboo-structure residential building prototype in China: Life cycle assessment of energy use and carbon emission

In this study, the material-based energy use and carbon emission over the life cycle of a bamboo-structure residential building prototype with innovative insulation technologies are analyzed. In comparison with a typical brick-concrete building, the bamboo-structure building requires less energy and emits less carbon dioxide to meet the identical functional requirements, i.e., envelope insulation and structure supporting. In order to systematically assess the energy use and carbon emission, several scenarios are designed based on the LEED standard and the technical potentials. The results indicate that there is a potential to reduce 11.0% (18.5%) of the embodied energy (carbon) for the use of recycled-content building materials and 51.3% (69.2%) for the recycling of construction and demolition waste, respectively. However, the practical effect of the potentials varies significantly depending on project management levels and available technologies in the current market. The analysis provides an insight into the assessment of the material-based energy use and carbon emission over the life cycle of a building.     

生命周期理论在城市公共建筑更新改造中的研究

生命周期理论发展至今,涉及了各个领域,然而其在建筑学领域的研究较为缺乏,但建筑可持续发展正是源于生命周期理论内涵的延伸。文章论述了生命周期理论应用于建筑更新改造的可行性,提出所面临问题,对其解决方法进行了研究和探讨,即如何构建公共建筑的生命周期辨析体系。最后以城市火车站为例进行初步分析与辨析体系建构,证明了其对城市公共建筑的更新改造有极高的指导意义。     

Alternative scenarios analysis concerning different types of fuels used for the coverage of the energy requirements of a typical apartment building in Thessaloniki, Greece. Part II: life cycle analysis

This paper constitutes a continuation of “Alternative scenarios analysis concerning different types of fuels used for the coverage of the energy requirements of a typical apartment building in Thessaloniki, Greece. Part I: fuel consumption and emissions”. It is concerned with the application of life cycle analysis (LCA) methodology to the model of the apartment building determined in Part I. The examination here includes emissions of light heating oil EL refining, transportation and combustion, of natural gas transportation and combustion and of electricity generation and use (lignite, natural gas, diesel oil and kerosene originated). All data used were collected from a typical power station in Greece.     

Formation, transformation and transport of black carbon (charcoal) in terrestrial and aquatic ecosystems

Black carbon (BC) is ubiquitous in terrestrial environments and its unique physical and chemical properties suggest that it may play an important role in the global carbon budget (GCB). A critical issue is whether the global production of BC results in significant amounts of carbon (C) being removed from the short-term bio-atmospheric carbon cycle and transferred to the long-term geological carbon cycle. Several dozen field and laboratory based studies of BC formation during the burning of biomass have been documented. Findings are difficult to interpret because they have been expressed in an inconsistent manner, and because different physical and chemical methods have been used to derive them. High error terms documented in many of these studies also highlight the problems associated with the quantification of the amount of biomass C consumed in fire, the amount of residue produced and the constituents of that residue. To be able to estimate the potential for BC as a carbon sink, issues regarding its definition, the methods used in its identification and measurement, and the way it is expressed in relation to other components of the carbon cycle need to be addressed. This paper presents BC data in a standard way; BC production as a percentage of the amount of C consumed by fire (BC/CC), which can be readily integrated into a larger carbon budget. Results from previous studies and new data from Australian ecosystems were recalculated in this way. As part of this process, several BC estimates derived solely from physical methods were discarded, based on their inability to accurately identify and quantify the BC component of the post-fire residue. Instead, more focus was placed on BC estimates obtained by chemical methods. This recalculated data lowered the estimate for BC formation in forest fires from 4% to 5% to <3% BC/CC. For savannah and grassland fires a value of <3% is consistent with reported data, but considerable variation among estimates remains. An updated flow-chart linking the sources, fluxes and pools of BC formed in the terrestrial environment with the aquatic and marine environments, and estimates of mean residence times for BC are also presented.     

Simplified method of sizing and life cycle cost assessment of building integrated photovoltaic system

This paper presents methodology to evaluate size and cost of PV power system components. The simplified mathematical expressions are given for sizing of PV system components. The PV array size is determined based on daily electrical load (kWh/day) and number of sunshine hours on optimally tilted surface specific to the country. Based on life cycle cost (LCC) analysis, capital cost (US$/kW_P) and unit cost of electricity (US$/kWh) were determined for PV systems such as stand-alone PV (SAPV) and building integrated PV (BIPV). The mitigation of CO₂ emission, carbon credit and energy payback time (EPBT) of PV system are presented in this paper. Effect of carbon credit on the economics of PV system showed reduction in unit cost of electricity by 17-19% and 21-25% for SAPV and BIPV systems, respectively. This methodology was illustrated using actual case study on 2.32 kW_P PV system located in New Delhi (India).     

建筑用抗震钢高应变低周及超低周疲劳性能研究进展

近年来全国各地高层建筑迅猛发展,同时我国已经进入第五个地震活动期,这对建筑用钢的高应变低周、超低周疲劳性能提出了严峻的挑战。用于制作抗震构件的低屈服点钢,作为抗震用钢的新钢种将会得到越来越广泛的应用。为此,本文介绍了国内外建筑抗震用钢的高应变低周、超低周疲劳研究现状,着重阐述了低屈服点钢的研发及其低周疲劳性能研究状况,探讨了提高钢抗震性能的措施,并指出了今后国内抗震用钢低周、超低周疲劳研究的方向,为进一步提高建筑用抗震钢的综合抗震性能提供借鉴。