The Cracking Resistance Behavior of Geosynthetics-Reinforced Asphalt Concrete under Lower Temperatures Using Bending Test

Abstract

Asphalt is a kind of temperature-sensitive material. With the decrease of temperature, the deformation capacity of an asphalt mixture will be significantly reduced. When the temperature is greatly reduced, the asphalt layer will produce large shrinkage tensile stress and strain, resulting in cracking. Therefore, the cracking resistance behavior is essential for the asphalt. In order to study the cracking resistance behavior of geosynthetics-reinforced asphalt under lower temperatures, the bending tests were carried out indoors at a temperature of −10 °C. The results showed that compared with the unreinforced asphalt sample, the flexural tensile strength at failure of the geogrid-reinforced sample was increased by 14.1% and 12.3%, corresponding to AC-13C and AC-20C. Additionally, the geotextile-reinforced sample was reduced by 2.5% and 3.6%, corresponding to AC-13C and AC-20C. The values of the bending stiffness modulus of the geogrid- and geotextile-reinforced samples were reduced by 6% and 1%. The cracking energy of the geogrid-reinforced asphalt provides by 45.2% and 30.8% more than unreinforced asphalt, corresponding to AC-13C and AC-20C. The cracking energy of the geotextile-reinforced asphalt is increased by 4.5% and 0.6% compared with unreinforced asphalt, corresponding to AC-13C and AC-20C. The cracking resistance behavior of geogrid-reinforced asphalt is better than unreinforced and geotextile-reinforced asphalt. The asphalt shows obvious brittleness at a temperature of −10 °C, and the existence of the geosynthetics does not change the shape of the load–deflection curves.