Numerical Simulation-Based Investigation of Fatigue Fracture Mechanisms in Hot In-Place Recycling of Asphalt Pavement

Hot in-place recycling (HIR) technology rejuvenates a certain depth range (typically not exceeding 6 cm) of old asphalt concrete pavement in a single step. Suitable for early-stage surface pavement distresses, it prevents them from progressing into deeper layers. Despite numerous experimental studies on the fatigue and fracture properties of hot recycled materials, limited research exists on numerical simulation of fatigue fracture in such materials. Numerical simulations, offering cost-effectiveness and overcoming size constraints, are the focus of this paper. The study uses a developed fatigue fracture co-simulation program to investigate fatigue fracture behavior in pavement structures under wheel load and temperature effects. It explores the influence of material properties, layer configurations, and initial crack positions of HIR materials on fatigue cracking occurrence. The research provides valuable insights into fatigue fracture patterns in HIR material pavement structures, offering a theoretical foundation for preventing fatigue fracture in such materials.