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Granite cutting waste is becoming a serious concern as the amount of waste produced is reaching monstrous proportions, thus making it virtually impossible to ensure proper disposal. The large volume of waste generated is dumped on to the dumping grounds nearby factory location. This unattended waste poses serious environmental and health threats and is an alarming call to seek out methods of production which may utilize this waste and thus lead to a cleaner environment. The research study aims at assessing the durability characteristics of the concrete incorporating this waste as a partial replacement for fine aggregate. The aim of the paper is to present a comprehensive, detailed and systematic picture of performance of the concrete thus obtained under adverse exposure conditions in terms of response to carbonation attack, sulphate attack, chloride ion penetration, acid attack and elevated temperature with variable w/c ratios. The test results clearly showed that modified granite cutting waste substituted concrete exhibits enhanced resistance to carbonation, chloride ion penetration, acid attack and exposure to elevated temperature at optimum granite cutting waste replacement of 25%. No loss in weight was observed at all durations of exposure to MgSO 4 solution. The specimen with 25% granite cutting waste replacement exhibited greater intensity and peak area for hydration products namely C–S–H and ettringite as compared to the control specimen. [ABSTRACT FROM AUTHOR]

Granite dust is a waste produced during cutting and grinding process of granite stone. The waste generation from granite stone industry is in the form of non-biodegradable fine powder, the utilisation of this waste in concrete will help in sustainable and greener development. Published literature shows huge potential of granite dust as a replacement of natural fine aggregate. The depletion of reserves of sand and stricter mining laws have made the need for substitution of natural sand in concrete an absolute necessity. A comprehensive overview of the published literature on the use of granite dust in concrete is being presented. Effect of granite dust on the properties of concrete such as workability, setting times, compressive strength, split tensile strength, flexural strength, shrinkage, durability & microstructure of concrete have been presented. [ABSTRACT FROM AUTHOR]

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]

In the present study, limestone (famous as Kota stone) mining waste reformed into aggregates of size between 19 mm and 0.075 mm were used to make bituminous concrete (BC) and dense bituminous macadam (DBM) by replacing conventional (Basalt) aggregates. Properties of LSW as aggregates was evaluated on the basis of physical parameters and mix performance. The mixes were evaluated on the basis of strength, durability, resistance to moisture and rutting. Results indicated suitability of LSA (Kota stone aggregates) as pavement material. Up to 50% replacement of conventional stone (CS) by LSA in BC mixes and 25% in DBM gave satisfactory results for moisture susceptibility, resistance to rutting and low temperature cracking. It was recommended to use LSA for making medium to low traffic roads. [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]

The paper explores the usefulness of hybridizing two distinct nature inspired computational intelligence techniques viz., Artificial Neural Networks (ANN) and Genetic Algorithms (GA) for modeling slump of Ready Mix Concrete (RMC) based on its design mix constituents viz., cement, fly ash, sand, coarse aggregates, admixture and water-binder ratio. The methodology utilizes the universal function approximation ability of ANN for imbibing the subtle relationships between the input and output variables and the stochastic search ability of GA for evolving the initial optimal weights and biases of the ANN to minimize the probability of neural network getting trapped at local minima and slowly converging to global optimum. The performance of hybrid model (ANN-GA) was compared with commonly used back-propagation neural network (BPNN) using six different statistical parameters. The study showed that by hybridizing ANN with GA, the convergence speed of ANN and its accuracy of prediction can be improved. The trained hybrid model can be used for predicting slump of concrete for a given concrete design mix in quick time without performing multiple trials with different design mix proportions. [ABSTRACT FROM AUTHOR]

• SF, MSP, and FA were incorporated in HSSCC mixes as potential cement substitute. • Mechanical, abrasion and microstructural performance of HSSCC mixes were assessed. • The Ca/Si ratio played an important role in the strength development. • The collective use of 10% MSP and 15% FA, with 5% SF showed excellent performance. An experimental program was conducted to evaluate the impact of silica fume (SF), marble slurry powder (MSP), and fly ash (FA) on the mechanical properties and abrasion resistance of high strength self-consolidating concrete (HSSCC). For this, Ordinary Portland Cement (OPC) was replaced by SF, MSP, and FA in various proportions in individual and simultaneous manner. Altogether sixteen numbers of concrete mixes were prepared. The mechanical properties were evaluated by performing compressive strength, split tensile strength, flexural tensile strength, pull-off strength tests. The microstructural analysis was also carried out using field emission scanning electron microscope (FESEM) and Energy-dispersive X-ray spectroscopy (EDS) techniques. Amalgamation of MSP and FA in HSSCC resulted in better mechanical performance. The combined use of SF, MSP, and FA in HSSCC at 5%, 10%, and 15%, respectively has produced the best results in terms of mechanical performance. The EDS analysis showed the effect of Ca to Si ratio in strength development and this ratio found to be crucial. A statistical approach also shows the significance of the SF, MSP, and FA on the test results. [ABSTRACT FROM AUTHOR]

• Improved fresh properties were found by introducing MCSW and FA in HSSCC. • FA used up to 25% in ternary mixes resulted in comparable compressive strength with the 5SF mix. • Combined use of MCSW up to 10% and FA up to 15% along with 5% SF resulted in better resistance to water absorption. • SEM analysis indicated improved microstructure by combined use of MCSW up to 10% and FA up to 15% along with 5% SF. Disposal of marble cutting slurry waste (MCSW) has acquired a disastrous proportion and is a leading cause of environmental and health-related issues. On the other hand, high strength self-compacting concrete (HSSCC) is being widely used which requires a higher quantity of cement and ultimately resulting in the substantial CO 2 emission to the environment. The aim of this study is to produce economical and eco-efficient HSSCC using MCSW, fly ash (FA), and silica fume (SF). This would help to beneficially use MCSW and minimize the need to use large quantities of cement in HSSCC production, thus significantly reducing CO 2 emissions. Total sixteen number of HSSCC mixes in binary, ternary and quaternary form were prepared by incorporating MCSW, FA, and SF as a replacement of cement. Among all HSSCC mixes, one mix was prepared with a 100% cement binder which was named as control mix. The impact on fresh properties was assessed by slump flow, T 500 time, V-funnel time, fresh density, L-box height ratio, J-ring flow, and J-ring step height. Mechanical performance in terms of compressive strength, and other properties like percentage of water absorption, percentage of voids, and dry bulk density were also examined. The microstructural investigation was carried out using the Scanning electron microscope (SEM) and Fourier transform infrared radiation (FTIR) techniques. It was observed that the incorporation of MCSW and FA improved the fresh properties of HSSCC. A combined use of 10% MCSW and 15% FA with 5% SF as cement replacement resulted in enhanced mechanical performance and amended microstructure. [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]

Industrial by products such as granite cutting waste (GCW) are suspected to have a detrimental effect on environment. This paper emphasizes on a sustainable way of getting rid of GCW by using it as a partial replacement of natural fine aggregate (river sand) in conventional concrete. In this paper, strength and durability behaviour of concrete containing GCW is examined so as to determine its viability in concrete production. Concrete was prepared with GCW in 4 different proportions i.e. 10%, 20%, 30%, and 50% and various tests such as compressive strength, flexural strength, abrasion resistance and permeability test were performed and the experimental values were compared with the control mix. Microstructural studies of control mix (CM) and mixes with different percentages of GCW were also performed using SEM and XRD techniques to identify effect of incorporating GCW on performance of concrete with respect to C–S–H gel, silica and other hydration products, which has not been investigated in the past. Microstructural investigation helps in understanding the variation in strength of concrete with different percentages of GCW. Test results, SEM and XRD analysis of concrete mixes indicates that optimum replacement percentage of fine aggregate with GCW is about 30% as the performance of concrete is significantly improved at this replacement level. Hence, GCW can be used as a partial substitute of river sand and thereby reducing cost of concrete production. Optimal replacement of sand by GCW can open up new avenues in sustainable construction techniques and reduce the detrimental effect on environment due to waste disposal. [ABSTRACT FROM AUTHOR]