Role of Aggregrate Types on De-Icing Salt Resistance of Ultra-High-Performance Conrete

In recent years, ultra-high-performance concrete (UHPC) has attracted interest from the research community because of its excellent physical, mechanical, and durability properties. However, due to its very high production cost, utilization of UHPC is very limited. In this context, a detailed experimental investigation was conducted to utilize locally-available fine aggregates in producing UHPCs that will help in reducing their production cost. This study reports on freeze-thaw resistance with deicing salt of the non-propriety UHPCs containing different fine aggregate and cementitious materials. Two distinct fine aggregate types, plaster sand and masonry sand, were each combined with coarser concrete sand to create a unique aggregate blend for the studied UHPCs. A total of 12 plain and fiber-reinforced UHPCs were batched using a uniform water-to-cementitious materials ratio of 0.21. The aggerate-to-cementitious materials ratio of 1.2 was kept uniform for all studied UHPCs. Due to the dense microstructure of the studied UHPCs, both masonry and plaster fine aggregates displayed similar resistance to freezing and thawing with deicing salt with mass losses ranging from +0.05% to −0.15% after 60 F–T cycles. The studied tertiary UHPCs exhibited reduced mass loss in comparison to that of the equivalent reference UHPC.