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In recent years, construction industry has seen huge demand for non-renewable materials such as stones, fine aggregate, coarse aggregate, etc., resulting in exponential growth in mining operation. In parallel to this, the quarrying of dimensional stone generates vast amount of waste in both solid and powder forms. Sustainable disposal of these wastes has emerged as a big challenge around the globe. The present research focusses on minimizing the environmental pollution which is often due to unplanned disposal of slurry waste generated during the cutting process. To carry out this study, eleven mortar mixes were prepared with dimension limestone slurry waste as a replacement of fine aggregate. These mixes were tested for their workability, porosity, ultrasonic pulse velocity, dynamic modulus of elasticity, water absorption, compressive strength, flexural strength and adhesive strength. The behavior of internal structure of mortar matrix was evaluated on selected mixes by TGA, FTIR, SEM and MIP techniques. Tests results revealed that up to 40 percent replacement of fine aggregate with dimensional limestone slurry improved strength and sustained necessary rheological parameters of mortar mixes. Results of microstructure studies substantiate these improvements. [ABSTRACT FROM AUTHOR]

• Potential use of dimensional limestone waste in cement mortar mixes has been evaluated. • Effect of dimensional limestone waste on drying shrinkage of mortar mixes has been studied. • Micro-structure analysis like FT-IR, XRD and SEM has been carried out on mortar mixes. The present study was undertaken to evaluate the potential of dimensional limestone waste (DLW), generated during cutting and polishing activity, as fine aggregate in mortar mixes. For this, the generated waste was used in two forms, first as slurry and second as manufactured sand. A total of fourteen mortar mixes (volumetric ratio 1:3 and 1:6) were prepared by replacing conventional fine aggregates (river sand) between 0 and 60% with dimensional limestone slurry (DLSS) and manufactured dimensional limestone crushed sand (DLCS). These mortar mixes were evaluated on the basis of workability, compressive, flexural, adhesive and tensile bond strengths, drying shrinkage, water absorption, porosity, density, ultrasonic pulse velocity, and dynamic modulus of elasticity. A positive impact of DLW on strength properties of mortar mixes was observed between 20 and 60% replacement of conventional river sand. Use of DLW resulted in a much denser and homogeneous mixture, reducing water-cement ratio, and improving the workability of mortar. Using DLW as partial replacement of fine aggregate resulted into improved strength properties of mortar. However, above 20% replacement, the drying shrinkage of all mortar mixes increased continuously. Structural matrix of mortar mixes, analyzed by scanning electron microscopy (SEM) images, Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) substantiate the above results. Use of DLW as partial substitution of conventional river sand may help to conserve the non-renewable natural resources with alternative building material. [ABSTRACT FROM AUTHOR]

The rapid rate of solid waste generation has led to a huge quantum of unattended wastes posing a major threat to the ecosystem. Over the years, concrete industry has acquired the credentials of being one of the largest consumers of some of the most vital natural resources. The cost of production of concrete has observed a sustained rise over a period of time and there has been an increasing shortage of fine aggregates, thus aggravating the situation further. Some serious concerns have been raised repeatedly over the detrimental effects of reckless extraction of fine aggregate from river beds. Cleaner production, which is a completely sustainable production process seems to be the calling of the hour, which on one hand aims a the eco-friendly disposal of this huge quantum of industrial waste and on the other hand provides an economical and viable source of raw material for concrete industry. The paper reviews the feasibility of a wide variety of industrial by-products such as bottom ash, waste foundry sand, copper slag, plastic waste, recycled rubber waste, crushed glass aggregate etc., as a potential replacement for fine aggregate in the concrete manufacturing process in terms of strength and durability characteristics. A framework for further research has been proposed to attain reliable, robust, eco-friendly and economic concrete as the end product. [ABSTRACT FROM AUTHOR]

• Review of studies pertaining to use of dimensional stone waste in mortar mixes. • Dimensional stone waste as fine aggregate in mortar improve strength and durability. • At higher substitution level dimensional stone waste as fine aggregate increase water demand and shrinkage characteristics. Dimensional stones are natural rocks that exhibit distinctive texture, vibrant colour and unique patterns. They are hard and durable, and, hence can be easily shaped into various shape and sizes; to be used as floor and cladding decorative purpose. Mining of these stones is highly unsustainable process producing tons of solid and slurry waste which pollutes the local environment. Studies are available where this discarded waste is used as a substitution of conventional construction and building material. The present review paper explores the effect of dimensional stone waste on workability, strength and durability properties when used as partial to full replacement in variety of mortar mixes. Reviews of studies suggest that the discarded waste improve compressive and tensile strength, enhances the durability characteristics and bond properties of mortar. However, the inclusion of this waste also increases the overall water demand to achieve the desired workability. The review of literature also highlights the shortcoming in the available literature and possible scope of research which are required in order to establish the use of dimensional stone waste as a construction material for mortar. [ABSTRACT FROM AUTHOR]