Effect of Red Mud Content on the Physical and Mechanical Properties of the Composites Fabricated using Recycled Pet Resin

Background: Red Mud (RM) is a solid waste produced by alumina production in the Bayer process. At present, it is being stored or dumped on the land or in the oceans. To utilize RM, extensive work has been done by the researchers to develop various techniques. The production of PC (Polymer Concrete) is one of the economical and efficient methods to recycle the RM. Methods: In this study, the RM has been utilized to fabricate the PC using the recycled PET resin as the binder with fly ash, silica fume and foundry sand as the fillers. By varying the RM content, the influence on the workability, shrinkage, ultrasonic velocity, toughness, modulus of elasticity, mechanical strength, water absorption and acid resistance has been observed. Results: For the specimens cured for 56 days, the values of compressive strength, flexural strength and split tensile strength have been increased by 20.26%, 49.11% and 61.99%, respectively. The water absorption has been reduced by 23.5%. Also, the loss in compressive strength under the effect of the 30%HCl has been decreased by 25%. Conclusion: The specimens containing 20% of red mud content have shown maximum values. Fine particles of RM have increased the mortar compactness and produced high-density PC with reduced density, and the ultrasonic pulse velocity has been reduced due to a decrement in density and modulus of elasticity values.