Recycling coral waste into eco-friendly UHPC: Mechanical strength, microstructure, and environmental benefits.

On islands far away from the mainland, the raw materials for concrete production are often more difficult to obtain. Converting the coral waste generated during the island construction process into a marine ultra-high performance concrete (UHPC) mixture is an eco-friendly strategy. Coral powder (CP) is used to partially replace cement and silica fume (SF), and its mechanical strength, microstructure and environmental benefits are evaluated.

Microstructure of ultra high performance concrete containing lithium slag.

Lithium slag (LS) is discharged as a byproduct in the process of the lithium carbonate, and it is very urgent to explore an efficient way to recycle LS in order to protect the environments and save resources. Many available supplementary cementitious materials for partial replacement of cement and/or silica fume (SF) can be used to prepare ultra high performance concrete (UHPC). The effect of LS to replace SF partially by weight used as a supplementary cementitious material (0%, 5%, 10% and 15% of binder) on the compressive strengths and microstructure evolution of UHPC has experimentally been studied by multi-techniques including mercury intrusion porosimetry, scanning electron microscope and nanoindentation technique.