沥青路面再生过程的环境影响评价及优化建模技术

Abundant researches have been carried out on the asphalt pavement recycling study, however, most of which focused only on the engineering domain and little has been devoted to the evaluation and modeling techniques of the environmental impact for the holistic recycling process. The primary goal of asphalt pavement recycling is to fully take advantage of used materials and thus to reduce the energy consumption and air emissions while the process itself is of extensive environmental impacts. This project obtains plenitude of energy consumption and air emission data through multiple approaches, including field investigation, laboratory test, etc. and simulates pavement recycling activities using discrete event model. Furthermore, it quantifies the influences of sources, properties and proportions of old asphalt mix on the environmental impacts of different recycling technologies and accordingly establishes the respective predictive models. A strict methodology is constructed to test the reliability of the established models. Optimization models, combining the elements of pavement performance, economic investment and environmental impacts, are developed to improve the asphalt pavement recycling decisions. The achievement of the project will spur the progress of the theoretical and quantitative evaluations of environmental impacts of asphalt pavement recycling and ultimately reduce the impacts during the processes.

沥青路面再生利用技术的研究备受关注，然而过往的研究主要侧重于再生工艺领域，鲜有对沥青路面再生利用全过程环境因素的评价与优化建模技术的研究。沥青路面再生的目的是充分利用旧有材料，降低能源消耗和空气污染物的排放，然而其实施过程却会造成巨大的环境影响。本项目通过现场试验、室内试验等获取能耗、空气污染物排放数据，利用离散事件模拟道路的施工条件；量化老化沥青混合料来源、性质、用量等因素的影响，建立沥青路面再生利用全过程的环境影响模型，提出模型可靠性评价的方法论；综合路用性能、造价和环境因素，优化再生方案的决策。项目的成果能够促使对沥青路面再生环境影响的评价向理论化、定量化方向转变，降低路面再生过程中的环境影响。

沥青路面再生的目的是充分利用旧有材料，减少道路材料生产运输施工等的能源消耗和空气污染物的排放，然而其再生过程本身也会带来巨大的环境影响。因此，本研究开展沥青路面再生环境影响评价，优化再生方案，降低再生过程的环境影响。通过本项目的研究，取得的主要研究成果如下：.1..就地热再生沥青路面性能模型：通过室内试验和收集就地热再生路段的路用性能数据，建立了就地热再生沥青路面路用性能（车辙、平整度和裂缝）回归模型，为优化沥青路面接地热再生方案提供数据支撑。.2..就地热再生环境影响评价与优化：依托实际工程，采集环境参数，构建了沥青路面就地热再生离散事件模型，评价了复拌再生法和复拌加铺法两种热再生工艺的环境影响；通过优化现有施工工序，两者的环境影响可分别降低11.6%和14.1%。.3..环境影响数据计算结果可靠性评价：基于设定的评价标准，评价采集的环境数据质量，将数据质量转化为改进的Beta分布；通过层次分析法获取不同组别环境数据的权重，开展Monte Carlo模拟，建立了环境影响计算结果的概率密度分布函数，分析其统计参数，评价计算结果的可靠性。.4..就地热再生方案多目标优化决策：构建以施工环境影响、施工成本、路面性能为决策变量的热再生方案多目标优化模型，通过NSGA-Ⅱ算法求解，获得20组Pareto最优解，可满足不同目标需求的就地热再生施工工艺优化。. 上述研究实现了沥青路面就地热再生环境影响的评价从定性化向定量化方向转变，量化了不同工况下的沥青路面再生过程的环境影响，为沥青路面再生方案的决策提供了指导。