Workability, strength, and shrinkage of ultra-high-performance seawater, sea sand concrete with different OPC replacement ratios
Shameer Saleh, Yinglei Li, Ehab Hamed, Aziz Hasan Mahmood, Xiao‐Ling Zhao
Abstract
An experimental investigation on the chemical, physical, mechanical, and shrinkage of seawater and sea sand-based ultra-high-performance concrete (UHP-SWSSC) with supplementary cementitious materials (SCM) (i.e. slag and silica fume) is reported. Several mixes were designed with varying proportions of SCMs (25%, 37.5%, 50%, and 62.5% of binder), aggregate source, and water-to-binder ratio. Heat evolution, density, workability, compressive strength development, and long-term autogenous and drying shrinkage of UHP-SWSSC were monitored. Seawater accelerates cement hydration as reflected in the heat evolution, and consequently, dictates the early-age strength, and autogenous shrinkage. SCM addition although limits the early-age strength development offers a comparable 90 days strength. The chloride content increases from marine resources and may limit the application to nonstructural components. Nonetheless, a UHP-SWSSC mix with 50% OPC replaced by 37.5% slag and 12.5% silica fume is recommended in this study, which can achieve satisfactory workability, long-term strength, and shrinkage properties.