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This paper provides an outlook on the effects of climate change and the severity and frequency of extreme weather events on the performance of flexible pavements across North America. Now more than ever, the climate is changing at a rapid pace, which will alter long-term environmental loading parameters and extreme weather events. Such alterations will pose implications for the design, maintenance, and rehabilitation of flexible pavements, especially in terms of their serviceability, safety, and functionality. In northern Canada, roads are founded on various terrain types, including thaw-sensitive ice-rich permafrost underlying terrains. Such roads have experienced signs of embankment and pavement damage, which are usually induced by the degradation of the underlying permafrost due to climate change. Therefore, the development and implementation of new permafrost thaw mitigation techniques for vulnerable roads are essential and will be discussed in this paper. Resilient flexible roads should be designed to withstand the conditions that are likely to occur during their design life, taking into account the impact of the climate change on pavement performance in response to daily and seasonal changes in heat, precipitation, freeze–thaw cycles, and extreme weather events. [ABSTRACT FROM AUTHOR]

The warming weakening of permafrost strength as a result of different scenarios of climatic warming ranging from 0 to 5°C over the next century has been predicted using a one-dimensional geothermal model. These predictions are based on the results of an intensive geotechnical program carried out in a warm ice-rich silty permafrost in Northern Quebec. The dependency of permafrost strength on temperature was assessed from cone penetration tests performed at regular intervals over a 2-month period during the seasonal warming of the upper permafrost layer in spring 2000. A thermomechanical subroutine taking into account this dependency has been then added to the one-dimensional geothermal model for the simulation of the weakening of permafrost strength as it warms. A warming rate of 0.02°C/year over the next century leads on a slow decrease in permafrost strength corresponding to a relative loss of strength of about 50%. For a warming rate of 0.05°C/year, the strength weakening is much more pronounced and almost reaches the unfrozen state at the end of the warming period corresponding to a relative loss of 98%. [ABSTRACT FROM AUTHOR]