Thermo-mechanical performance evaluation of pavement materials in cold regions

Arian Asefzadeh
2019
A pavement system is a multi-layer structure that provides ease of ride for commuters by successfully transferring the traffic-induced loadings to the ground. A typical flexible pavement structure is comprised of Hot Mix Asphalt (HMA), the strongest material in terms of strength, overlying the Granular Aggregate Base (GAB) layer placed on top of subgrade soil which is the weakest material. Each pavement material has its own properties and mechanical characteristics, thus, each respond to
more » ... and environmental loading, differently. Pavement materials in cold regions are exposed to inclement weather conditions including prolonged winter seasons, short thawing periods and long summer days. Therefore, pavements are prone to several damages and distresses in cold regions. Rutting and fatigue failure are the two main distresses which occur due to lack of sufficient stiffness in the HMA and subgrade layers. This research study aims to evaluate the performance of spring load restriction models used by transportation agencies during crucial periods using field environmental and falling weight deflectometer tests data. HMA is highly sensitive to temperature changes which significantly affect its dynamic modulus. Subsequently, because of high temperature variation between cold and warm seasons in cold regions, the HMA layer experiences damages such as thermal cracking and rutting in cold and warm seasons, respectively. Statistical temperature prediction models were developed and successfully calibrated based on the environmental data collected from field. To evaluate the field performance of HMA layer, statistical temperature prediction models were developed and calibrated based on field weather and asphalt temperature data. Implementing triaxial testing, the permanent deformation and resilient modulus of subgrade materials were evaluated and modeled. The effect of using waste recycled material such as bottom ash and tire derived aggregates were evaluated on the strength of the subgrade soil and fatigue life performance of the pavements. This study was fruitful and proved the satisfactory fatigue life performance of pavements constructed on embankments made with tire derived aggregates. iii
doi:10.7939/r3-4539-y997 fatcat:gvzs7xsv7jdatkts3ke4f7wiym