Integrated approach for analyzing Effects of Surface Permeability on Lomg Term Performance of Asphalt Pavements

交通基础设施，特别是高速公路，在加拿大和世界其他国家的国民经济中发挥着重要作用。因此，它们需要大量的投资来建造新建道路和人行道以及维护现有的网络。然而，从历史上看，沥青路面在建造能够满足其预期设计寿命的道路方面一直面临着重大问题。在包括加拿大人在内的世界上许多地方，许多新建的沥青道路的早期失效迫使政府和道路管理者搜索和调查其他类型的道路，例如波特兰水泥混凝土和/或使用各种添加剂和加强格栅，以延迟所观察到的沥青道路的早期劣化。本研究调查建立在申请人进行的早期研究工作的结果和发现的基础上，申请人应用理论和基础研究的结果来开发创新和适用的技术，以实现设计和建造沥青路面道路的目标，从而满足其预期的长期设计目标。建议的研究的主要推力是综合施工裂缝，渗透性和沥青路面层之间的粘结的影响，模拟热横向裂缝的传播。所开发的模型将通过实验室和现场实验进行验证。研究结果将用于升级AASHTO热裂缝预测模型。 该研究的意义在于其对加拿大沥青道路长期性能的影响，特别是在严寒环境条件下。目前的研究，处理热开裂现象没有处理的“萌生”的裂纹在一个综合的方式，考虑理论，实验和现场研究。本研究遵循一种独特的研究方法，即从更好地了解热开裂“开始”的实际原因开始，通过初步的实验室模拟来支持这种理解，然后制定热开裂问题预测模型的基本原则。研究计划将带来显著的节省和效益。首先，了解支配问题的变量将有助于提出可靠和有效的解决方案。第二，可靠的解决方案将导致新技术的设计和生产，以降低维护沥青杆的成本和费用，使其经受严寒天气，如我们的加拿大之一。这项研究有望扩大对一个古老的挑战性问题的科学知识，这个问题已经知道了世纪多，但没有可靠的解决方案。此外，一个直接的好处将是防止每年再次出现的坑洞在加拿大的许多沥青道路，特别是那些其首都渥太华。

Transportation infrastructures in general and highways in particular plays significant role in the national economy of Canada as well as other countries of the world. Therefore, they require large amounts of investments for building new roads and pavements and maintaining existing networks. However, historically, asphalt pavements have been facing significant problems in terms of building roads that can meet their projected design lives. The early failure of many newly constructed asphalt roads in many parts of the world including Canadians are forcing the governments and road administrators to search and investigate other types of roads such as Portland cement concrete and/or the use of various additives and reinforcing grids to delay the observed early deterioration of asphalt roads. This research investigation builds on the results and findings of early research work carried out by the applicant which applies findings of theoretical and basic research to develop innovative and applicable technologies to achieve the goal of designing and building asphalt pavement roads that will meet their expected long term design objectives. The main thrust of the proposed research is to integrate the effects of construction cracks, permeability, and bond between asphalt pavement layers to model the propagation of thermal transverse cracks. The developed model will be validated using lab and field experiments. The outcome will be used to upgrade the AASHTO Thermal crack predictive model. The significance of the research is its impact on the long term performance of asphalt roads in Canada especially under severe cold environmental conditions. The current studies that deal with the phenomenon of thermal cracking do not deal with the “initiation” of the cracks in an integrated manner which considers theoretical, experimental and field studies. This research follows a unique research approach in that it started by developing better understanding of the actual causes of the “initiation” of thermal cracking, support the understanding with preliminary laboratory simulation followed by formulating the basic principles of predicting model of the thermal cracking problem. Significant savings and benefits will result from the research program. First, the understanding of the variables governing the problem will help proposing reliable and effective solutions. Second, reliable solutions will lead to design and production of new technologies to reduce the costs and expenses of maintaining asphalt rods subjected to severe cold weathers such as our Canadian one. The research expected to expand the scientific knowledge of an old challenging problem that has been known for more than a century without a reliable solution. Furthermore, an immediate benefit will be the prevention of the annual reappearance of the potholes on many of Canada’s asphalt roads and specially those of its capital city Ottawa.