ANALYSIS OF MECHANICAL PROPERTIES OF CONCRETE PARTIALLY REPLACED BY QUARRY DUST AND GROUND GRANULATED BLAST FURNACE SLAG

Abstract

Industrial by-products were used in concrete production because natural river sand resources were depleted and traditional concrete manufacturing methods created environmental problems. The research examined how M30 grade concrete performed through its mechanical strength testing and durability assessment and microstructural analysis when it used sandstone quarry dust to partially replace natural sand. The researchers created concrete mixes with different replacement levels of quarry dust which included 10% 20% 30% 40% and 50% to test workability and density and compressive strength and split tensile strength and water absorption and captivity and chloride ion permeability across various replacement percentages. The research findings showed that workability declined as quarry dust content increased because the dust particles possessed angular shapes and contained more fine material. The 40% replacement level showed a density and mechanical strength improvement because of better particle packing and lower porosity. The control mix reached 28-day compressive strength of 36.13 MPa which increased to 41.83 MPa at 40% replacement for the test. The split tensile strength showed the same improvement as the other strength test results.

The study showed that building materials achieved better durability through the addition of quarry dust because their water absorption and sorptivity values decreased with higher replacement amounts, which resulted in better water resistance. The test results for rapid chloride permeability demonstrated that the material at its optimal replacement rate showed enhanced protection against chloride ion penetration. The microstructural examination through SEM found that the material developed fewer pores while attaining better bonding strength between its components, and the XRD analysis showed that quarry dust functioned mainly as an inert filler which did not change the cement hydration process. The study results proved that the ideal quarry dust replacement amount for construction materials should be set at 40% because this proportion delivers optimal strength, durability, and workability properties. The research established that quarry dust serves as a sustainable substitute for natural sand which enables the production of concrete that exhibits long-lasting strength while maintaining environmental sustainability.