Improving Sustainability and Durability of Pavement Structures in Cold Regions

在有限的资源和极端温度下建设和维护大型道路网络是加拿大运输机构面临的一个挑战，特别是在草原地区。膨胀土和高质量骨料的枯竭是建造低维护路面结构的额外挑战。土/团聚体稳定技术可用于提高膨胀土和不良团聚体的稳定性和刚度。然而，在寒冷气候下，稳定的土壤/骨料层的耐久性是一个问题。稳定层长期性能的巨大不确定性限制了它们在寒冷地区的使用。除了上述挑战之外，塑料废物的管理对市政当局来说也是一项环境挑战，因为它不会随着时间的推移而降解。虽然塑料废物可以通过回收利用从堆填区转移，但一些塑料废物不能在国内使用的产品中回收利用。为了解决这个问题，一些研究调查了塑料废物在生产沥青混合物中的使用。虽然它显示出一些希望，但只有有限数量的研究调查了含有塑料废物的沥青混合物在寒冷地区的性能。这项研究计划的长期目标是为寒冷气候下的路面设计和施工确定经济和可持续的解决方案。通过减少与创新施工技术相关的不确定性，优化有限资源的使用，以及在路面施工中使用回收材料，可以实现这一长期目标。拟议研究计划的具体短期目标如下：a.评估不同稳定技术对研究区域可用土壤、骨料和气候条件的适用性。b.使用基于性能的加速实验室测试表征稳定土和骨料层的耐久性和长期性能。c.研究寒区沥青混凝土混合料中使用塑料废弃物的可行性。d.利用成像技术表征含有塑料废物的沥青混凝土混合物的特性和冻融耐久性。e.根据本研究项目的研究结果，提供在寒冷地区使用塑料废物用于沥青混合物和稳定土壤和骨料层的指导方针。f.提高学生对路面材料高级测试和路面结构设计方法的知识和技能。该研究项目将对提高寒冷地区路面结构的可持续性和耐久性产生重大影响。因此，运输机构和市政当局将优化有限预算的利用，这对寒冷地区和加拿大大草原的机构来说是一个挑战，并减少路面建设的碳足迹。

The need to construct and maintain large road networks with limited resources and under extreme temperatures is a challenge to Canadian transportation agencies, especially in the prairie region. Expansive soils and depletion of high quality aggregates are additional challenges to constructing low-maintenance pavement structures. Soil/aggregate stabilization techniques can be used to increase stability and stiffness of expansive soil and poor aggregates. However, durability of stabilized soil/aggregate layers is a concern in cold climates. The large uncertainty associated with the long-term performance of stabilized layers is a limitation to their use in cold regions. In addition to the above challenges, management of plastic waste has been an environmental challenge for municipalities because it does not degrade with time. While plastic waste can be diverted from landfills through recycling, some plastic waste materials cannot be recycled in domestically used products. To address this problem, several studies have investigated the use of plastic waste in production of asphalt mixtures. While it has shown some promise, only a limited number of studies have investigated the performance of asphalt mixtures containing plastic waste in cold regions. The long-term objective of this research program is to identify economic and sustainable solutions for pavement design and construction in cold climates. This long-term objective can be achieved by reducing uncertainty associated with innovative construction techniques, optimizing the use of limited resources, and using recycled materials in pavement construction. The specific short-term objectives of the proposed research program are as follows: a. Evaluate the suitability of different stabilization techniques for the available soils, aggregate materials, and climatic conditions in the study region. b. Characterize the durability and long-term performance of stabilized soil and aggregate layers using performance-based accelerated laboratory testing. c. Investigate the feasibility of using plastic waste in asphalt concrete mixtures in cold regions. d. Utilize imaging techniques to characterize the properties and freeze-thaw durability of asphalt concrete mixtures containing plastic waste. e. Provide guidelines for using plastic waste in asphalt mixtures and stabilization of soil and aggregate layers in cold regions based on the findings of this research program. f. Improve knowledge and skills of students related to advanced testing of pavement materials and design methods for pavement structures. The research program will have a significant impact on improving the sustainability and durability of pavement structures in cold regions. As a result, transportation agencies and municipalities will optimize the utilization of limited budgets, which is a challenge for agencies in cold regions and Canadian Prairies, and reduce the carbon footprint of pavement construction.