Permafrost roadbed protection and potential application of lightweight cellular concrete as an eco–friendly protection technology in China: A review

Road construction in frozen areas faces significant challenges due to frost heaving, thaw settlement, and permafrost degradation, which compromise infrastructure stability and longevity. Traditional protection methods, however, often struggle to balance efficiency, cost–effectiveness, and environmental sustainability. Through a comprehensive review of previous studies, this work summarizes existing protection technologies, highlighting their advantages and limitations and emphasizing the urgent need for sustainable, eco–friendly, and cost–effective materials to improve permafrost roadbed protection. Lightweight cellular concrete (LCC) is proposed as a promising alternative. This study systematically reviews the development, classification, and current applications of LCC in road engineering. The related properties of LCC are also discussed, with particular emphasis on its low density, high strength–to–weight ratio, and unique porous structure, which enhance thermal insulation and freeze–thaw resistance. In addition, LCC reduces the use of non–renewable aggregates, lowers material consumption, and facilitates reuse. Incorporating fly ash and silica fume further improves sustainability and strength while reducing CO 2 emissions. Carbonation curing of LCC enhances durability and CO 2 sequestration. Future research should focus on improving early strength, integrating industrial byproducts, and scaling up CO 2 –curing. As LCC technology advances, it is expected to make a significant contribution to the sustainable development of permafrost infrastructure and the reduction of greenhouse gas emissions. • Existing protection techniques are difficult to balance efficiency, cost-effectiveness, and environmental sustainability. • Lightweight cellular concrete (LCC) offers low density, high strength-to-weight ratio, and superior thermal insulation. • LCC reduces non-renewable aggregate use, enhances freeze-thaw resistance, and allows material reuse. • Integrating fly ash, silica fume, and CO 2 curing improves strength, durability, and carbon footprint. • Future should focus on early strength enhancement, large-scale industrial byproduct use, and CO 2 -curing optimization.