Low-carbon concrete pavement incorporating LC3: Mechanical, durability, and environmental evaluation

The extensive use of Ordinary Portland Cement (OPC) in concrete pavements has become a major concern due to its significant contribution to greenhouse gas (GHG) emissions and environmental degradation. In recent years, the use of various materials to replace and reduce clinker consumption in the production of various types of pavement concrete has expanded. Limestone Calcined Clay Cement (LC3) has gained attention as a sustainable option for reducing environmental pollutants and improving mechanical properties, with a composition of 55% OPC, 30% calcined clay, and 15% limestone powder. In this study, mechanical properties including compressive strength and flexural strength, durability against freeze-thaw cycles, relative dynamic modulus of elasticity, and environmental analysis of pavement concretes made with LC3 and OPC at binder contents of 300, 400, and 500 kg/m3 were comprehensively evaluated and compared. The results of this research showed that LC3 concretes exhibited better compressive and flexural strength at 90 days compared to OPC concretes. Additionally, the durability of LC3 samples against damage caused by freeze-thaw cycles was significantly higher, and they exhibited less reduction in the dynamic modulus of elasticity. Environmental indicators were also examined, revealing that using LC3 in concrete pavements reduced CO2 emissions by up to 36% and significantly improved the Human health, Ecosystems, and Resources indicators. Overall, the results of this study indicate that LC3 has significant potential for constructing pavements with high mechanical properties and a lower environmental impact.