Thermal anti-cracking investigation of asphalt-based seal technology for airport base layer in frozen ground region

Abstract

In frozen ground regions, the problems of subgrade frost damage and slab cavity were common distresses of cement concrete pavement in civil airports, causing the major safety hazard during the daily operation of airport. It was necessary to explore prevention technology of airport pavement subgrade due to frost damage. This research investigated the anti-cracking and thermal properties of asphalt-based composite seal as intermediately isolated airport base layer in cold regions. The stiffness and stress relaxation behaviors of binders were evaluated at low temperatures by bending beam rheometer test, in terms of various modifiers with styrene-butadiene rubber and liquid nitrile rubber. Based on the dissipation energy method, the viscoelastic characteristics of asphalt materials were analyzed with Burgers model. Additionally, the response regions of low-temperature rheology were expanded through the master curve establishment of flexural creep compliance. The thermal properties of binder were characterized by thermal gravity analysis and differential scanning calorimetry test. Finally, the relationships between various indices were conducted to release the polymer modification impacts on thermal cracking resistance of asphalt-based seal technology through statistical analysis. This study revealed that the cracking resistance and thermal properties of asphalt-based composite seal at low temperature was essential and efficient and should be recommended the consideration for airport pavement in cold regions.