Frost-Heave and Thaw-Weakening Susceptibilities of Granular Recycled Pavement Materials: Experimental Results

In the wake of escalating environmental concerns and the urgent need for sustainable constructions, recycled materials have been widely studied and employed for road projects, while their durability especially under freeze-thaw cycles limits the applications in seasonal frost regions. This technical note presents laboratory testing results and preliminary assessment regarding the freeze-thaw performance of granular recycled pavement materials. Utilizing recycled portland cement concrete (RPCC), recycled asphalt pavement (RAP), and RPCC/RAP mixtures, this research evaluates the frost-heave and thaw-weakening susceptibilities under controlled laboratory conditions. Key findings indicate that California bearing ratio (CBR) values cannot reliably predict frost-heave susceptibility, with RPCC/RAP mixtures displaying balanced performance and relatively low CBR reduction after freeze-thaw cycles, underscoring their potential for pavement base applications. The study also reveals no direct correlation between frost-heave and thaw-weakening susceptibilities, highlighting the complexity of freeze-thaw dynamics. These insights contribute significantly to the development of durable, ecofriendly pavement materials, promoting sustainable development in the construction industry.