铁路线路生命周期内的环境影响定量评价

Life cycle assessment on railway line engineering

基于生命周期评价理论(Life Cycle Assessment,LCA)和生态指标法,建立铁路线路生命周期内环境影响定量评价模型.对铁路线路从建筑原材料生产、建设施工到开通运营直至拆除等生命周期各个阶段,采用人类健康损伤、生态系统破坏、资源能源消耗3个终点破坏评价模型,按照评价目的和范围的确定、清单分析、分类和特征化计算、标准化和加权分析4个步骤,对铁路线路生命周期内的环境影响作定量评价,并以某铁路线路为例,进行生命周期内的环境影响定量评价.结果表明:在铁路线路生命周期中,资源能源(含运营列车能耗)消耗对环境影响所占的比例最大,约占线路生命周期内对环境全部影响的67%;生态系统破坏次之,约占21%;对人类健康损伤最大的时期是在施工阶段;对生态系统破坏和资源能源消耗最大的时期是在运营阶段;运营阶段对环境影响的贡献最大,施工阶段次之.

Based on the theory of life cycle assessment （LCA） and ecological indicator method, a quantitative environmental impact assessment model of the railway line engineering in its life cycle was established. By means of four steps, namely, goal and scope determination, life cycle inventory analysis, classification and characteristic calculation and normalization and weighting analysis, an end-point damage model was established in this paper, and three categories of impact （ecosystem, human health, energy and resource） were selected. To verify the applicability of this model, a case study was carried out. The results show that energy and resource consumption （including energy consumed for train＇s moving） have the greatest environmental impact, accounting for 67 % of the life cycle impact, followed by ecosystem destruction accounting for 21%. In addition, the construction stage has the great- est effect on human health damage, the operation stage has the greatest effect on ecosystem destruction and energy and resource consumption. In the life cycle of the railway line engineering, the operation stage has the greatest environmental impact, followed by the construction stage.