An Experimental Investigation of Utilizing Waste Red Mud in Soil Grouting

In this work, the utilization of Red Mud (RM) with Portland Cement (PC) in soil grouting was investigated. For this study, samples were prepared with cement and 0%, 5%, 10%, 15%, 20%, 25%, and 100% red mud contents to grout a poorly graded Sand Soil (SP). Unconfined compressive strengths of the grouted and pure grout samples were determined after 7 and 28 days hydration. Furthermore, XRD, SEM, and TG/DTG analyses were performed on the pure grout samples after 28 days of hydration. The texture of the grouted and pure grout samples were examined using digital cameras capable of zoom photography. The maximum unconfined compressive strength was obtained from the grouted and pure grout samples composed of 15% red mud and 85% Portland cement. Incorporating the red mud with Portland cement increases the consumption of portlandite (Ca(OH)(2)) formed during cement hydration; this was observed in the XRD, SEM, and TG/DTG analyses. Spherical voids were formed in the grouted and pure grout samples after 28 days of hydration depending on the amount of red mud. It was shown that using 15% red mud in the soil grouting gave positive results in terms of strength and portlandite content.