Sustainable Approach for Using M-Sand Slurry as a Controlled Low Strength Material

Abstract

The national-level practice of handling and disposal of industrial wastes create many challenging environmental implications including extensive pollution, resource seclusion and economic losses. The assessment of potentiality for their reuse and/or recycling has conceived tremendous opportunity in various engineering applications with a clear insight of circular economic sustainability. Meanwhile, the handling and disposal of mining wastes were posing serious environmental challenges for their substandard engineering properties. To restore the conventional, backfill materials, a flowable fill known as controlled low strength materials (CLSM) consisting of various ingredients of fine aggregate-sized materials can be employed. In general, CLSM mixtures consist of routinely available materials such as Portland cement, fly ash, fine aggregate, and water. It was expected that the vital characteristics of the mixture, such as flowability, excavatability, and requirements of minimum mechanical strength compared with concrete enable the use of industrial wastes for the production of CLSM. The present study deals with the feasibility of regenerating the silt fraction of M-Sand, known as M Sand Slurry (MSS), to be used for the creation of flowable fills. Mix proportions are developed based on the plastic and mechanical properties with a small quantity of cement and water content. Preliminary plastic (flowability) and hardening properties (compressive strength) results indicate that' s the possibility of the effectiveness of MSS by minimizing the cement addition (up to a maximum of 6%) to attain the unconfined compressive strength above 0.7MPa as per the specifications recommended by ACI standards. It was proposed that an optimum combination of materials can be effectively incorporated in preparing CSLM materials while reducing the requirements of cement, thereby analysed the cost benefits for sustainable developments.