Environmental and economical friendly ultra-high performance-concrete incorporating appropriate quarry-stone powders

Quarry stone powder is one of the solid waste, which can create obvious environmental risks. To solve this problems, 22.2%-44.4% of cement is replaced by two types of quarry stone powder (basalt and limestone powders) in producing an environmentally-friendly ultra-high performance concrete (UHPC) in this study. The material mix design is followed on the basis of the modified Andreasen and Andersen (MAA) model. Then, the impact of the quarry stone powders on fresh and hardened properties of UHPC are investigated, including flowability, compressive strength, early hydration kinetics, and durability. The results indicate that the incorporation of quarry stone powder can significantly improve the flowability, slow down the early hydration rate of cement and decrease autogenous shrinkage of UHPC during early age. Besides, the addition of quarry stone powder could decrease the strength of UHPC at 7 days, while its strength is comparable with the reference mix at 56 days. The carbon dioxide (CO2) emissions calculation shows that application of quarry limestone powder can significantly reduce the environmental burden of UHPC, which means the produced UHPC can be treated as a green building material with advanced properties in the near future. (C) 2020 Elsevier Ltd. All rights reserved.