Crack Formation in Asphalt Mixtures in the Wheel Tracking Test at High Temperature

Dense graded asphalt

The formation of internal cracks in asphalt mixtures in the wheel tracking test at high temperature was investigated in dense graded (13F) and drainage asphalt mixtures prepared outside. Such cracks are caused by movement of aggregates in asphalt mixtures with distance separation in the crossing direction under passes of the testing wheel. The movement of aggregates during the wheel tracking test (1 h, 2500 passes) at 0 passes, 600 passes, 1900 passes and 2500 passes was analyzed by photography. Greater deformation of aggregates in asphalt mixtures occurred at 50-60 mm from both tire ends in the case of dense graded asphalt mixture (13F) and at both tire ends in the case of drainage asphalt mixture. Local strain in those areas exceeded the maximum failure strain of the mixtures in the tensile test. Internal cracking may occur under passes of the wheel at high temperature, and cracks may appear in the surface with time, which has not been considered until now.