Engineering Properties of Red Mud and other by-Products based Controlled Low-Strength Material

Abstract

Controlled low-strength material (CLSM) also known by names such as flowable fill or controlled density fill is self-compacted in nature and used in civil engineering works such as backfills, void fills, conduit bedding and many more. These materials have strength lesser than 8.3 MPa. Generally it consists of Portland cement, fine aggregate, fly ash and water but several other materials such as foundry dust, quarry dust can also be used. In this study the different engineering properties of CLSM with different mix proportion was evaluated. Mix proportion mainly consists of red mud having 70%, 60% and 50% by weight of total composition along with fly ash, crusher dust and phosphogypsum was studied. Portland cement was used as the binder material in all the composition in the proportion of 10% and 7% of the above composition. For different mix proportions considering flow value as an important parameter firstly percentage of water required for desired flow value (150-300mm) was evaluated by trial method and then then at those water content along with above mixture other important engineering properties of CLSM such as compressive strength, bleeding and durability was evaluated. Except the property of reexcavatibility (strength lesser than 2.1 MPa) for some composition all the other properties of all the composition were within the permissible limit. In overall it can be stated that Red mud can be effectively used as one of the material in CLSM.