The mechanical, transport and chloride binding characteristics of ultra-high-performance concrete utilising seawater, sea sand and SCMs

•Studied the durability of seawater and sea sand-based ultra-high-performance concrete (SWSS-UHPC) with supplementary cementitious materials (SCM).•Non-destructive tests (i.e., ultrasonic pulse velocity, and electrical resistivity) were correlated to the mechanical and durability properties.•The chloride binding capacity was determined.•SCMs offer a significant enhancement in transport properties and durability.•Electrical resistivity can successfully predict chloride penetration resistance.