Investigation of the influence of various curing regimes on the early-stage compressive strength of ultra-high-performance concrete

This paper investigates the effect of various moisture and temperature curing regimes on the early-stage compressive strength of ultra-high-performance concrete (UHPC). The primary aim of this research is to determine the optimal curing conditions for achieving maximum compressive strength in this advanced concrete type. The UHPC mixture utilized in this study included sand as the fine aggregate, high-purity silica fume, Type ۱ Portland cement, water, and a polycarboxylate-based superplasticizer for reducing the water-to-cement ratio. A key aspect of UHPC curing process is the activation of silica fume, which requires suitable temperature for chemical reactions in order to develop superior mechanical properties. Therefore, this study examined the impact of different moisture and temperature conditions on ۵۰-mm cubic samples. The UHPC specimens were cured at three temperatures: ۲۵°C (ambient temperature), ۵۰°C, and ۱۱۰°C, to clearly observe the effect of temperature on the pozzolanic reactions of silica fume and cement hydration process. Submerged water curing at ۱۱۰°C proved to be the most effective method for enhancing UHPC early-stage compressive strength, leading to the attainment of the highest compressive strength. These findings emphasize the importance of providing sufficient moisture alongside appropriate temperature to accelerate reactions and optimize UHPC performance.

کلیدواژه ها:

Ultra-High-Performance Concrete (UHPC) ، Early-stage Compressive Strength ، Moisture and Temperature Curing ، Silica Fume