Evaluation of mechanical properties and durability of concrete with provided marble dust from Kurdistan

Marble dust is an industrial by-product that has recently been used as a mineral powder to improve the mechanical properties of concrete. Furthermore, since large amounts of marble dust is available in the waste of stone crushing plants in areas like Kurdistan, employing this powder in the process of making concrete reduces both environmental pollution and the final price of concrete. In this paper, an experimental study was conducted to evaluate the effects of using marble dust as a partial replacement of sand in concrete on slump, 28-day compressive strength, and durability at 28 days. To this end, 180 cubic specimens with 30 mixing designs were tested at the age of 28 days. Studied mixing designs by considering two general groups include three ratios of water to cement (0.4, 0.45, and 0.5) with five ratios of marble dust to sand (0, 0.05, 0.1, 0.15, and 0.2) for each water to cement ratios, and two fineness moduluses of 2.4, and 3 for each groups. The results indicated that partial replacement of sand with marble dust in concrete has different effects on concrete slump. Whereas, it improves compressive strength and decreases permeability of concrete. Moreover, it was found that for each of water to cement ratios, and for both quantities of fineness modulus of sand, increasing marble dust-to-sand ratio from 0 to 20%, increases the compressive strength by 5 to 16% with respect to its respective control specimen. In addition, the results indicated that for each of water to cement ratios, and for both amounts of fineness modulus of sand, increasing the marble dust to sand ratio from 0 to 20%, decreases the depth of water penetration by 55 to 79% with respect to its respective control specimen.