Study of the Interlocking Filling–Graded Composition Design Method of an Asphalt Mixture Mixed with Shape-Memory Epoxy Resin Fibers

Abstract

Under the comprehensive action of environmental temperature and vehicle loads, asphalt pavement is prone to certain issues, such as high-temperature wheel ruts. Thermally activated shape-memory epoxy (SMEP) resin is a new kind of intelligent polymer material that can sense temperature changes and respond by adjusting the mechanical parameters back to their initial state. Adding thermally activated shape-memory epoxy resin to an asphalt mixture can improve its high-temperature performance and water stability. This paper incorporated shape-memory epoxy resin fibers into asphalt mixtures. First, AC-13 asphalt mixtures mixed with and without SMEP were tested with a Marshall experiment. The results showed that the AC-13 asphalt mixture mixed with SMEP swells. To solve this problem, an interlocking filling–graded composition is proposed. A local optimization algorithm was used to study the graded composition, and the corresponding equations and processes are proposed. The Marshall test of the interlocking filling–graded composition indicated that the values of porosity and voids in mineral aggregate (VMA) of the asphalt mixture produced with 4.75-mm sieve pores were greater than the values obtained for the asphalt mixture produced with 2.36-mm sieve pores. Moreover, the bulk density and stability of the asphalt mixture produced with 4.75-mm sieve pores were less than those obtained for the asphalt mixture produced with 2.36-mm sieve pores. The optimal interlocking filling–graded composition was produced with 2.36-mm sieve pores and a 6% mineral powder. The interlocking filling–graded composition in this paper solves the aforementioned expansion problem when incorporating SMEP into an ordinary graded composition, enriching the graded composition design method of asphalt mixtures.