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The excessive consumption of river sand as a construction material has led to its acute scarcity. Researchers across the globe have attempted to utilize waste of copper slag, rubber tyre, recycled glass, pond ash, foundry sand, plastic, stone etc. as a partial or complete substitute of river sand in concrete. The present study investigates the feasibility of using granite cutting waste (GCW) as a partial substitute of river sand in high strength concrete based on strength, durability & microstructural attributes. Eighteen concrete mixes were cast at 0.30, 0.35 and 0.40 water cement ratios (w/c) by substituting 0%, 10%, 25%, 40%, 55% and 70% river sand by GCW. The concrete mixes were tested for compressive, flexural strength, abrasive resistance, permeability, water absorption, carbonation, corrosion and microstructure; changes in morphology and hydration were also studied. Test results suggested that 25–40% river sand can be substituted by the GCW with a favourable influence on the investigated parameters. The optimum amount of GCW to be used in concrete depends significantly upon water-cement ratio of concrete. [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]

• 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]