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The performance of bituminous materials is mainly affected by the prevailing maximum and minimum temperatures, and their mechanical properties can vary significantly with the magnitude of the temperature changes. The given effect can be observed from changes occurring in the bitumen or asphalt mixture stiffness and the materials’ serviceable life. Furthermore, when asphalt pavement layer are used, the temperature changes can be credited to climatic factors such as air temperature, solar radiation and wind. Thus in relevance to the discussed issue, the contents of this paper displays a comprehensive review of the collected existing 38 prediction models and broadly classifies them into their corresponding numerical, analytical and statistical models. These models further present different formulas based on the climate, environment, and methods of data collection and analyses. Corresponding to which, most models provide reasonable predictions for both minimum and maximum pavement temperatures. Some models can even predict the temperature of asphalt pavement layers on an hourly or daily basis using the provided statistical method. The analytical models can provide straight-forward solutions, but assumptions on boundary conditions should be simplified. Critical climatic and pavement factors influencing the accuracy of predicting temperature were examined. This paper recommends future studies involving coupled heat transfer model for the pavement and the environment, particularly consider to be made on the impact of surface water and temperature of pavements in urban areas.

Since 2001, the Highways Agency in the UK have been involved in a joint research project on economic evaluation of long life pavements, in collaboration with a number of national institutions under the umbrella of the Organisation for Economic Co-operation and Development/European Conference of Ministers of Transport. Specifically, the project examined the feasibility of introducing road surfacing materials with a service life in excess of 40 years [also known as long life surface course]. This target service life is at least twice as long as that typically expected from surfacings currently used in road pavements and would need to be demonstrated by the performance of any candidate materials. Herein the findings from an assessment of asphalt surfacing materials typically used in the UK, but modified with an epoxy binder, and their suitability for use in long life surface course, are presented. The work reported focuses upon evaluation of stiffness and tensile strength of manufactured specimens; in other related work, significant improvement in deformation resistance of epoxy asphalt has been reported. The research compliments other studies by participating laboratories in Denmark, New Zealand and the USA which have confirmed epoxy asphalt as a premium material that outperforms conventional binders on the important indicators of potential long service life.

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