Road Performance of Hot Central Plant Versus Hot In-Place Recycling Asphalt Mixtures: A Quantitative Comparison and Adaptability Analysis

Despite being crucial for sustainable pavement construction, the widespread application of hot recycled asphalt mixtures in high-grade surface courses is hindered by concerns over their long-term performance, particularly regarding cracking resistance and moisture stability. This study systematically evaluates the road performance of hot central plant recycling (HCPR with 30% RAP) and hot in-place recycling (HIPR with 80% RAP) mixtures, benchmarked against virgin hot mix asphalt (SMA-13), through comprehensive laboratory simulations. The enhancing effect of basalt fibers (BFs) was thoroughly investigated. Results revealed a significant performance trade-off; while the recycled mixtures exhibited superior high-temperature stability (e.g., an 80.7% increase in dynamic stability for HIPR), their cracking resistance substantially decreased with higher RAP content (e.g., reductions of 60.8% in low-temperature flexural strain and 22.1% in intermediate-temperature fracture energy for HIPR). Both recycled mixtures also showed susceptibility to moisture damage, evidenced by stripping in Hamburg wheel-tracking tests. The incorporation of BFs effectively mitigated these deficiencies. It comprehensively improved the performance, enabling the HCPR mixture to meet specifications for severely cold regions and elevating the HIPR mixture to compliance level for cold regions. Furthermore, BF significantly enhanced rutting resistance under coupled hydrothermal conditions. These findings demonstrate that basalt fiber reinforcement can bridge the performance gap of recycled mixtures, thereby expanding their application scope and providing a robust technical basis for selecting and optimizing recycling strategies in high-grade pavement engineering.