Mix design and comprehensive road performance assessment of fluid mastic asphalt

Marshall method and Superpave method often lead to problems such as bleeding and decreased high temperature stability when increasing asphalt content. It is difficult to take into account high temperature stability and low temperature crack resistance. In order to break through this limitation, based on the design concept of Mastic Flow for Filling method (MaFF), the paper develops a new FMA-13 mixture by optimizing the skeleton structure and asphalt mastic design. Taking AC-13 mixture as the reference group, the key road performance of FMA-13 mixture, such as high temperature stability, low temperature crack resistance, water stability, fatigue durability and surface skid resistance, was systematically evaluated. The test results show that the comprehensive road performance of FMA-13 (7.0) is significantly better than that of AC-13. In terms of high temperature stability, the dynamic stability of FMA-13 (7.0) is 41.6% higher than that of AC-13. The maximum bending strain of FMA-13 (7.0) mixture reached 3764με at -10°C, and the fracture energy of the SCB test was 1.94 times that of AC-13 at 5°C. This shows that FMA-13 (7.0) not only improves the high temperature stability, but also significantly improves the low temperature crack resistance, which effectively solves the contradiction between the two. In addition, FMA-13 has excellent water stability, and the residual stability of immersion Marshall is as high as 98.8%. Under the strain levels of 400με, 600με and 800με, the fatigue life of FMA-13 (7.0) is 2.56 times, 2.17 times and 1.62 times that of AC-13, respectively. And the initial BPN value of FMA-13 (7.0) can reach more than 67, which has good anti-sliding performance. What’s more, the attenuation rate of BPN and TD is 27.9% and 26.3% lower than that of AC-13 under 300,000 times of wear. In summary, FMA-13 mixture shows significant advantages in the comprehensive road performance, which provides a new technical way to improve the durability and sustainable development of asphalt pavement and has broad application prospects.