Understanding the ternary interplay among mechanical, environmental and economic attributes of seawater sea-sand engineered cementitious composite (SS-ECC)

Seawater sea-sand engineered cementitious composite (SS-ECC) not only offers a solution to the challenge of natural resource depletion but also exhibits excellent properties, rendering it highly promising for widespread marine applications. Nonetheless, its environmental impact assessment remains unclear, and the correlation between mechanical performance and environmental effect lacks detailed investigation. In order to tackle this problem, this study conducts a comprehensive analysis. First, normal-strength and high-strength SS-ECC are reinforced with polyvinyl alcohol (PVA) and polyethylene (PE) fibers, respectively, with counterparts utilizing river sand and freshwater as the control group. Uniaxial tensile tests on dog-bone specimens and compression tests on cubic specimens are performed to determine the mechanical properties of ECC in relation to saline content. Furthermore, an assessment of abiotic depletion fossil (ADP), global warming potential (GWP) and cost of ECC are performed in accordance with prevailing standards. Major findings indicate that saline content enhances the early compressive strength of normal-strength (by 28.6 %) and high-strength (by 13.3 %) ECC. High-strength SS-ECC exhibits superior tensile performance, achieving an early tensile strength of 6.94 MPa and a tensile strain of 6.85 %. Additionally, saline content significantly reduces the ADP (by 9.07 %), GWP (by 7.04 %) and cost (by 9.10 %) per compressive strength unit in high-strength ECC. Further research reveal that high-strength SS-ECC outperformed normal-strength SS-ECC in national infrastructure project with scores enhanced by 210.94 %. • SS-ECC demonstrates ultimate tensile strength of 6.94 MPa and tensile strain of 6.85%. • Trade-off relationship between mechanical performance and environmental effect is established. • Saline content reduces SS-ECC's ADP by 9.07%, GWP by 7.04% and cost by 9.10%. • High-strength SS-ECC scores 210.94% higher than normal-strength SS-ECC.