Abstract:

Asphalt concrete roads will be subjected to various factors such as vehicle loads， temperature changes， and rainwater erosion during long-term use， resulting in some disease problems. To effectively enhance the performance of concrete， the influence of polypropylene fibers on the properties of modified asphalt concrete is studied. The polypropylene fiber was pretreated by pretreatment， and the fiber modified asphalt concrete was prepared by mixing the treated polypropylene fiber with matrix asphalt and aggregate. The performance of asphalt concrete prepared with different matrix asphalt dosage and different fiber content was tested by Marcel mix ratio design method to determine the content of matrix asphalt and fiber， and the influence of fiber length on the performance of the asphalt concrete was determined by rut test. The test results showed that the content of matrix asphalt increased. The volume relative density and stability of asphalt concrete first increase and then decrease， and the performance is the best at 4%. The volume density and stability are improved when the content of 3% polypropylene fiber is increased， but the performance is reduced when excessive. The longer polypropylene fiber reduces the damage probability， but the longer polypropylene fiber affects the fiber dispersibility. The asphalt concrete rutting test results are the best when the fiber length is 26 mm.

Key words: Polypropylene fiber, Asphalt concrete, Fiber length, Marshall, Rutting test