▎ 摘　　要

NOVELTY - Concrete admixture comprises fiber system (I), and fiber system (II), where fiber system (II) comprises chopped basalt fibers coated with silane, the fiber system (II) comprises 80,000 wt.% of the total volume of the admixture, the fiber system (II) comprising chopped basalt fibers coated with silane 9.734 wt.% of the total volume of fiber system (I), graphene nanoplatelets under 10 microns in size 1.027 wt.% of the total volume of fiber system (I), calcium sulfide 2.053 wt.% of the total volume of fiber system (I), calcium chloride 2.053 wt.% of the total volume of fiber system (I), magnesium oxide 2.053 wt.% of the total volume of fiber system (I), and nano clay 3.080 wt.% of the total volume of fiber system (I), where fiber system (I) comprises 20,000 wt.% of the total volume of the admixture. USE - Concrete admixture for preparing cementitious composition with non-potable water such as potable water, fresh water, saltwater, and brackish water. ADVANTAGE - The concrete admixture has increased the overall compressive strength and has been reduced by the amount of admixture added to shorten cure times, has reducing the amount of cement used, and introducing locally sourced aggregates, coarse and fine, to yield ultra-high-Performance concrete, has increased compression strength, has improved cure times, has reduced water consumption and corrosion, has increased durability and workability, drastically has reduced freeze-thaw effects, and has superior crack control. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a cementitious composition, which comprises a cement, the concrete admixture, and non-potable water with a salinity of 30,000-40,000 mg/L, such as saltwater.