Effect of Marble Powder Waste as a Partial Replacement of Cement on Fresh and Mechanical Properties of Self Compacted Mortar

Self-compacting concrete and mortar have revolutionized the construction sector but are more expensive to produce due to higher cement consumption and additives. To reduce the cost, cement can be replaced by CRMs. In this study, the main focus was to produce a high quality together with environmentally friendly self-compacting mortar. For this purpose, MD as CRM was employed at 0, 5, 10, 15, 20, and 30% fractions for both NSC and HSC series with w/c ratios of 0.50 and 0.38, respectively. Fresh properties of SCM were evaluated by slump flow, flow rate, consistency retention, air content (%), and setting time. While the hardened properties of SCM were assessed by unit weight, compressive, splitting tensile, flexural strengths, water absorption, drying shrinkage, and heat degradation at (100 ºC, 200 ºC) which evaluated by the change in compressive strength, rebound number by Schmidt hummer, and UPV by pundit. Observed data indicates that the spreading flow and the air content (%) were decreased with increasing the replacement level, while the flow rate T20, and setting time were increased. The lowest spread flow, and air content (%) were found at a 30% replacement level. Similarly, the lowest prolonging in flow rate T20, and setting time were found at a 5% replacement level compared to the control mix. Moreover, there was a decline in unit weight, strength values, and drying shrinkage. While there was an increase in water absorption when increasing the replacement level. The lowest decrease in unit weight, compressive, splitting, and flexural strengths compared to the control mix was at 5% MD for both NSCM and HSCM series. Likewise, the lowest reduction in the drying shrinkage was found at a 15% replacement level for both NSCM and HSCM series. Furthermore, a satisfactory mortar quality with MD before and after heat exposure was demonstrated by Pundit test results. After exposure to the heat of 100 and 200 degree centigrade, a decrease in compressive strength, Schmidt hummer, and UPV were noted. Keywords: Marble Dust (MD), Cement Replacement Materials (CRM), Normal Strength Self-Compacted Mortar (NSCM), High Strength Self-Compacted Mortar (HSCM), Workability, Mechanical Properties, Durability.