Performance Evaluation on the Strength of Nano-Enhanced Ultra-High-Performance Concrete under different Curing Regimes

Abstract

Ultra-High-Performance Concrete (UHPC) is characterized by its exceptional mechanical strength and dense microstructure; however, its performance is strongly influenced by curing conditions and the incorporation of advanced nano-scale materials. In this research the impact of nano-titanium dioxide (Nano-TiO₂) on the mechanical performance of UHPC under various curing regimes is investigated experimentally. UHPC mixture of M120 grade was prepared by incorporating Nano-TiO₂ at dosages of 1%, 2%, and 3% by weight of the cement binder. The prepared specimens were subjected to normal water curing, oven curing and accelerated thermal curing conditions, and their compressive strength was evaluated at different curing ages. The results reveal that the strength development of UHPC is considerably modified by the addition of nanomaterial, with the level of improvement varying according to the type of nanomaterial and the curing regimes. Due to improved particle packing, dispersion effects, and cementitious matrix modification, a 2% nano-material content often produced the best mechanical performance among the studied dosages. Nano-TiO₂ exhibited a positive influence on the strength development of M120 UHPC, with its effect becoming more evident at later curing ages. Overall, the results show that maximizing strength development, improving the UHPC matrix, and attaining superior mechanical performance all depend on the synergistic optimization of nano-material dosage and curing regime. This provides an effective method for the production of high-strength and high-performance UHPC.