This　study　explores　the　use　of　granite　powder　(GP),　a　by-product　of　manufactured　sand,　as　a　partial　replacement　for　sand　and　fly　ash　(FA)　in　three-graded　concrete.　Experimental　results　show　that　replacing　10-15%　of　sand　with　GP　improves　workability,　with　an　optimal　water-powder　ratio　of　0.37　increasing　slump　by　17.6%.　Compressive　and　flexural　strengths　peak　at　15%　GP　replacement,　with　increases　of　6.73%　and　3%,　respectively,　at　28-day.　Moderate　GP　levels　enhance　cracking　resistance,　increasing　cracking　time　by　20.67%.　Microscopic　analysis　reveals　improved　matrix　compactness　and　reduced　porosity　due　to　the　filler　effect　of　GP.　Excessive　GP,　however,　reduces　strength　due　to　higher　water　demand.　This　study　demonstrates　GP＇s　potential　to　enhance　concrete　performance　while　promoting　sustainable　waste　recycling,　reducing　reliance　on　natural　sand,　and　lowering　carbon　emissions,　offering　an　eco-friendly　solution　for　hydraulic　engineering　applications.