Life cycle assessment of composite concrete columns made of high-performance concrete skin with recycled aggregate concrete core

Abstract

Concrete and cement production are among the largest industrial sources of CO₂ emissions. Reducing their carbon footprint relies on enhancing concrete durability and promoting the use of recycled materials. This study explores a hybrid structural concept combining a high-performance concrete (HPC) skin with a recycled aggregate concrete (RAC) core. The environmental advantages of HPC stem from its superior mechanical strength and durability, which enable the design of slender structures, thus minimizing material consumption. In this composite system, the durable HPC skin safeguards the more permeable RAC core against carbonation, thereby extending service life. Simultaneously, the RAC core contributes to the overall ductility and fire resistance of the structure. This integrated approach expands the structural applicability of RAC while ensuring efficient use of HPC. The primary objective of this study is to assess and quantify the environmental benefits arising from the use of these composite systems.