Performance evaluation of asphalt mixtures subject to climatic effect

As extreme and unpredicted weather events are increasing, considering climatic effect on civil engineering structures is becoming a primary concern. The transportation system is one of the most important Civil Engineering Infrastructures. Pavement is a fundamental element in the transportation system. Most of the models used in evaluating pavement designs are based on the applied traffic load repetitions. However, there are other factors affecting the service life of asphalt pavements, such as environment and climate conditions. Previous studies showed that the response of a pavement system is highly dependent on its temperature. Temperature of pavement surfaces can be affected by numerous factors, such as air temperature, precipitation, and speed of wind as well as solar radiations. Temperature data is important to determine the amount of stress acting on a pavement surface. Thus, the deflection of pavements is highly influenced by its temperature. Temperature is also a main contributor to multiple types of pavement distresses, resulting in a significant impact on the service life of the pavement. The objective of this thesis is to investigate the effect of temperature variations on the performance of asphalt pavements. Four different climate factors will be considered. In part one, the behavior of asphalt mixtures in resisting low temperature cracking is evaluated. The study is done by comparing the low temperature properties of two types of asphalt binders: styrene-butadiene-styrene (SBS) modified asphalt binder and conventional asphalt binder, through laboratory tests and numerical analysis. In part two, the effect of freeze-thaw cycles on asphalt mixtures is studied, by conducting numerical simulations and finite element analysis. In part three, the impact of extreme high temperatures on the behavior of asphalt mixtures is studied, through laboratory tests and numerical analysis. In part four, the influence of solar radiations on the performance of asphalt concrete pavements is investigated, through the performance of computer software analysis and solar radiation modeling. Based on the outcomes of the different case studies, conclusions and recommendations are presented for future research needs on evaluating the climate effect on the behavior of asphalt mixtures