| Global warming and energy security have become important issues that China needs to face for the future development.The problems of greenhouse gas emission,pollutant emission and energy consumption in road transportation system are the key topics of energy conservation and emission reduction in China.The full life cycle of roads involves the stages of road material acquisition,construction,maintenance and demolition,and the full life cycle of vehicles involves the stages of vehicle material acquisition,manufacturing,operation and scrap recovery.At present,the environmental impact of the full life cycle of urban road traffic integrated with roads and vehicles are still unclear.The construction of the urban green assessment system based on the quantitative results of environmental impact assessment of urban road traffic full life cycle has not been well develpoed.Meanwhile,the new vehicle technologies generated by different technical routes are constantly emerging,and the prediction and assessment of the full life cycle environmental impact of urban road traffic under different technical parameters is still unclear.Therefore,it is of great theoretical and practical significance to carry out the research on urban road traffic full life cycle evaluation model which integrated roads and vehicles,to construct the urban road traffic green evaluation index system,to quantitatively predict the urban road traffic life cycle environmental impact,to deeply explore the influencing factors and path planning development of urban road traffic.Based on this,the main contirbutions of this paper are as follows:(1)The green evaluation index system and theoretical calculation model of urban road traffic based on full life cycle assessment is proposed.The full life cycle of urban road traffic is divided into the stages of raw material acquisition,construction and manufacturing,operation and maintenance,and dismantlement and scrap.The assessment models of material depletion,energy consumption,environmental emission and environmental impact in the full life cycle of urban road traffic are constructed,and the environmental impact and resource consumption in the whole life cycle are quantified and analyzed.The green evaluation index system of urban road traffic is built from four aspects: environmental impact,resource consumption,social economy and traffic function.The results of environmental impact and resource consumption in the whole life cycle of urban road traffic provide important research support for the green evaluation index system of urban road traffic.(2)The environmental impact assessment and the green assessment of urban road traffic have been carried out.Based on the real data of road traffic in Xi’an Aerospace New City,the data of road materials such as asphalt,cement and stone are analyzed,the energy consumption data of construction machinery required in the process of road construction,maintenance and demolition are analyzed.The data of materials,manufacturing,operation and scrap recovery of road running vehicles are analyzed as well.The life-cycle environmental impact assessment model of urban road traffic was used to analyze the life-cycle material resource depletion,fossil energy consumption,global warming potential,acidification potential,water eutrophication potential,ozone layer depletion potential and photochemical smog potential of road traffic in Xi ’an National Civil Aerospace Industrial Base.The results of vehicle life cycle environmental impact are higher than those of road life cycle environmental impact.The green evaluation index system of urban road traffic based on the whole life cycle evaluation is used to evaluate the scientific green evaluation of Xi’an National Civil Aerospace Industrial Base.(3)A new green evaluation method for the whole life cycle of urban road traffic with different vehicle types,different levels of intelligent connectivity and matching different power battery scenarios is proposed.Different vehicle types cover the traditional fuel vehicles,hybrid vehicles,plug-in hybrid vehicles,pure electric vehicles and fuel cell vehicles,anddifferent intelligence levels range from emergency auxiliary to the fully automatic driving,and different power batterysuch as lithium iron phosphate ternary lithium batteries,lithium manganese acid lithium titanate battery and battery.The results show that the pure electric vehicles matched with lithium iron phosphate batteries contribute the most to the green development of urban transportation,and the current technological level of fuel cell vehicles is not conducive to the green development of transportation.The higher the degree of intelligence of intelligent connected vehicles,contributes more to the green development of urban transportation.With the increase of intelligent networked level from driver assistance to fully automatic driving,the green evaluation result of the whole life cycle of urban roads improved by 2.4%.(4)Based on the life cycle assessment and multi-scenario simulation,a new idea of green evaluation and prediction of urban road traffic is innovatively proposed.Based on the current policy and key technology development trend of China’s power structure,vehicles lightweighting,vehicle energy consumption per hundred kilometers and the changes of different vehicle types,the urban road traffic whole life cycle environmental impact evaluation model and urban road traffic green evaluation index system are used to quantitatively predict the urban road traffic whole life cycle green evaluation results.The study shows that the green evaluation result of the whole life cycle of urban road traffic in 2035 is increased by 5.3%compared with that in 2020.Study of urban road traffic green development path for improving the material recycling system,focusing on promotion of pure electric vehicles and developing networked cars,optimizing the urban power structure and its energy transformation,optimization of urban road traffic spatial layout and accelerate the construction of green infrastructure,and determining the carbon calculation method and accounting standards system.The urban road traffic green evaluation index system and theoretical calculation model based on the whole life cycle proposed in this paper and the research conclusions drawn through empirical analysis have important reference values for the green construction of similar urban road traffic systems and are of great significance for the in-depth implementation of green development strategies in road traffic construction. |
