The Influence of Fibers on the Flexural and Tensile Properties of Asphalt Mastic Based on Finite Element Simulation

To improve the low-temperature crack resistance of asphalt pavement, this paper investigates the effects of fiber length, content, and type on the flexural and tensile properties of asphalt mastic. Firstly, a numerical program was developed in MATLAB to establish a three-dimensional finite element model of asphalt mastic with an uneven fiber distribution in ABAQUS. Then, the Burgers model selected for simulation was obtained through the asphalt low-temperature bending beam rheological test (BBR). Constructing a three-point bending virtual test of asphalt mastic using a three-dimensional fiber model and systematically analyzing the influence of fiber parameters on bending and tensile properties. The accuracy of the three-dimensional fiber model was verified through BBR experiments. The finite element simulation results show that the addition of fibers can significantly improve the tensile performance of asphalt mastic; increasing the fiber content or length can reduce the peak stress at the bottom of the mid-span and delay cracking. The higher the fiber elastic modulus, the smaller the vertical displacement of the specimen. The model established in this article can effectively elucidate the mechanism of fiber reinforcement, providing a theoretical basis for optimizing fiber parameters and improving the crack-resistance performance of asphalt pavement.