Mechanical, tidal erosion, and drying shrinkage behaviour of high performance seawater concrete incorporating the high volume of GGBS and polypropylene fibre

Abstract

Utilization of seawater as a mixing water can reduce demand for freshwater and lowers the carbon footprint of concrete production, making it an environmentally significant solution. This study explored the effect of incorporating polypropylene fibre (PPF) and a high volume of ground granulated blast furnace slag (GGBS) (as a 50% replacement of ordinary Portalnd cement) on the strength and durability parameters of high-performance concrete (HPC). According to the results, the use of seawater has an enhancing effect on the early-stage strength of HPC made with or without GGBS, as it accelerates the hardening process. In long term (over 28 days), the strength properties of seawater concrete produced with 100% OPC were slightly reduced as compared to corresponding freshwater concrete. However, for seawater mixes made with GGBS, strength properties improved with the age, and these mixes achieved high later strength than the seawater mixes made with 100% OPC. The inclusion of seawater and PPF yield a positive effect on the early-stage strength of GGBS-containing mixes. The drying shrinkage strain increased with the use of seawater, and it further increased due to the incorporation of GGBS. However, PPF reinforcement drastically reduced the shrinkage problem of the seawater mix. The wetting-drying cycle-induced erosion was significantly reduced by the inclusion of both GGBS and PPF, indicating their benefit in controlling the degradation of seawater mix in a tidal environment.