A DLCA-based Residential Building Environmental Impact Assessment Model And Method

Residential buildings consume lots of resources and discharge considerable emissions for large quantities in China,bringing serious damage to ecosystem.Scientifically evaluating a residential building’s environmental impacts is the premise of improving its environmental performance.LCA-based evaluation models,methods,standards and tools for buildings are developed maturely and used widely worldwide,but the temporal dynamic issues in buildings’ long life cycle have not been considered systematically in evaluation.At present,building environmental impact assessment abased on DLCA(Dynamic Life Cycle Assessment)is still in its infancy,and there is a lack of systematic research on DLCA connotation,assessment framework,dynamic evaluation elements,and quantitative evaluation methods.On the base of literature review and theoretical analysis,this thesis identifies the connotation of DLCA,and the basic features of dynamic evaluation elements.Based on the LCA evaluation principles and a mature LCA-based building environmental impact assessment model in China,logical relationship and data transformation relationship analysis are carried out,and then four dynamic evaluation elements,including consumption,basic inventory data,characterization factors and weighting factors,as well as their major influence factors are proposed.By integrating dynamic evaluation elements with the existing LCA evaluation paradigm,a DLCA-based environmental impact assessment framework is developed with the features of residential buildings into consideration.Quantitative assessment methods/models of dynamic consumption,dynamic basic inventory data and dynamic weighting system are developed to transform the DLCA evaluation framework to an operational model.Dynamic evaluation method for consumptions in the whole life cycle is put forward by analyzing the time-related variations of influence factors(i.e.construction related consumptions,service lives of components,recycling levels of wastes,occupants’ behaviors and so on)using scenarios,questionnaire,simulation,and others.The proposed method makes it possible to evaluate the time-varying resource and energy consumptions in the building’s life cycle before it is constructed.Dynamic basic inventory data for energy,power and main recoverable building materials are established on the variance evaluation of energy mix and energy input in the manufacture of building materials.And abased on distance-to-target approach,a dynamic weighting system including weighting factors in short,medium and long terms is developed with emission targets and resource characteristics,supporting scientific decision-making with different environmental protection priorities in periods into consideration.A residential building is taken as case to demonstrate the application of the developed model.Evaluation results using DLCA and traditional LCA models are compared abased on factor analysis method,quantifying the contributions of different dynamic evaluation elements to the evaluation results.Sensitivity analysis of some influence factors are also conducted.Results testify the necessity and validity of the DLCA model to some extent.As a constructive study in the area of DLCA-based building environmental impact assessment,this research develops an effective DLCA-based environmental impact assessment model with dynamic evaluation elements,assessment framework and quantitative evaluation methods included.It is of theoretical value for further developing the LCA-based environmental impact assessment system,and of practical reference value for improving the effectiveness of building environmental performance management and decision-making.