Faculty Publications
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Item Constructive scope on implementation of copper slag as replacement for natural fine aggregate—an overview(Springer Science and Business Media Deutschland GmbH, 2021) Thilak Kumar, Y.T.; Arpitha, D.; Sudarshan, V.J.; C, C.; Puttaswamy, N.This paper communicates organized work on copper slag drawn from scientific literature which comprises evaluation of physical and chemical characteristics, mechanical and durability properties in the marine environment. Analysis of test data derived from previously available sources reveals that copper slag having similar basic characteristics is an acceptable alternative material to river sand to produce concrete of all grades. The lesser water absorption property of copper slag is very significant peculiarity which attributes to develop high strength in concrete. The behaviour of concrete produced using copper slag to the concrete made corresponding to sand component shows identical behaviour in the fresh and hardened states. As an aggregate, copper slag has an ability to be replaced with fine aggregate, thereby the advance progress in the concrete technology will revolutionize the mixture of different conventional ingredients to uplift the expected properties of concrete to renew its definition. Hence, alternative materials to be used as fine aggregate will reduce the burden on the environment which is being extensively investigated all over the world looking to the significant requirements, quality and properties which have been a global consensus on the materials. © Springer Nature Singapore Pte Ltd 2021.Item Influence of copper slag properties on behaviour of cement mortars and concrete(Springer Science and Business Media Deutschland GmbH, 2021) Arpitha, D.; C, C.The promotion of green infrastructure as an alternative to traditional concrete, known as grey infrastructure, is not as benign as many people think. In this concern, many alternative materials have been kept in place as a solution for the problems faced by the construction industry. The knowledge of understanding the basic property of a material is significant as the characteristics cannot be directly assumed that it can be compared to FA while mixing concrete. In this work, Copper Slag (CS) is used as a partial replacement for Fine Aggregate (FA), and a major focus is to understand the behaviour of the material based on its particle size, texture shape and surface characteristics as it decides the quality of concrete. Also, the importance of optimizing water/cement ratio (w/c) and dosage of Superplasticizer (SP) is a major consideration in this work which has a great impact on workability and strength parameter as it affects durability performance of concrete. Marsh cone test to decide optimum SP was carried out for PCE-based SP and Portland Pozzolana Cement (PPC). Optimal w/c ratio was decided based on the trials carried out using flow test for mortars, and mortar cubes were prepared and tested for 3, 7 and 28 days compressive test. In order to check the behaviour of CS in concrete, cubes were prepared and subjected to compressive strength for 7, 28 and 90 days based on the ideal water–cement ratio (w/c) and SP obtained from various trials conducted to achieve required workability and strength. Test results revealed that CS mortars and concrete exhibited higher strength than the control mix. The chemical reaction between the cement matrixes, incorporation of CS and SP for optimized w/c and dosage of SP not only enhanced the strength but also provided the required workability though CS has less water absorption capacity. © Springer Nature Singapore Pte Ltd 2021.Item Study on Compatibility Issues and Flow Behavior of Copper Slag-Based Mortars(Springer Science and Business Media Deutschland GmbH, 2021) Thilak Kumar, Y.T.; Arpitha, D.; Sudarshan, V.J.; C, C.; Puttaswamy, N.With the growing constructions industries, sand availability has become a headache for the builders and engineers. In this paper an attempt has been made to understand the flow characteristics of partially replaced copper slag (10, 20, 30, and 40%) in mortars with varied water binder ratio (0.35, 0.4, and 0.45) for different percentages of superplasticizers dosage (0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, and 2.0). Thus, the test results drawn help to identify the optimum dosage of superplasticizer required for different percentage replacement of fine aggregates and water binder ratio and understand the flow behavior characteristics of mortars. © 2021, Springer Nature Singapore Pte Ltd.Item A Sustainable Approach to Turn Plastic Waste into Useful Construction Blocks(Springer Science and Business Media Deutschland GmbH info@springer-sbm.com, 2021) Monish, K.; Jesuran, J.J.; Kolathayar, S.The world economy is surging and newer technologies are evolving with the time. The construction sector is about to undergo a huge transformational change. The people of the world are looking forward to residing in houses made of sustainable materials. The people are concerned about increasing levels of greenhouse gases in the atmosphere. The cement production is accompanied by huge greenhouse gas emissions. On the other hand, waste plastics are becoming a nightmare for the people residing in developed and underdeveloped countries, as the waste management becomes difficult in those places. This research discusses a potential solution to address the above-stated issues of concern, i.e., plastic waste into construction blocks with lower cost and rapid construction phases. A study was conducted to examine the effectiveness of using LDPE (Low-Density Polyethylene), (major sources of waste and least recycled plastic) with waste materials like bottom ash, copper slag, and ceramic in different proportions to create blocks. This study compares the mechanical properties of different mix proportions of raw materials to find an optimum composition. This paper also investigates the pre-eminence of the newly developed composite block over the conventional brick in terms of economic viability, environmental sustainability, and construction superiority. © 2021, Springer Nature Singapore Pte Ltd.Item Performance of alkali activated slag concrete mixes incorporating copper slag as fine aggregate(Elsevier Ltd, 2016) Mithun, B.M.; Narasimhan, M.C.In this present study, copper slag (CS) is proposed as an alternative to river sand as fine aggregate in alkali-activated slag concrete (AASC) mixes. The relative performance of alkali activated slag concrete mixes with CS as fine aggregate is compared to conventional Ordinary Portland Cement concrete (OPCC) mix in terms of their workability, strength and durability parameters. The results indicate that, AASC mixes with CS, as a replacement to sand upto 100% (by volume), show no marked loss in strength characteristics. AASC mixes with either sand or CS possess similar modulus of elasticity, lower total porosity, lesser water absorption and reduced chloride ion penetration as compared to OPCC. Strength-retention characteristics of AASC mixes with sand/CS on exposure to sulphate and acid-rich environment are also studied. Use of AASC mixes for structural application reduces carbon footprint, decreases water consumption and cost. Use of CS as fine aggregate reduces river sand consumption as an added benefit. © 2015 Elsevier Ltd. All rights reserved.Item Study on Durability Properties of Sustainable Alternatives for Natural Fine Aggregate(Springer, 2021) Arpitha, D.; C, C.The present work focused on the durability performance of copper slag (CS) and processed granulated blast furnace slag (PGBS) as a partial replacement (0% to 50%) for natural fine aggregate (NFA) in concrete, cured for 365 days. This work was carried out to determine the ingression of chloride, sulphate, and sodium ions. Compressive strength test and splitting tensile test conducted for the specimens showed that PGBS concrete attained higher strength followed by CS concrete when compared to conventional concrete. The ingression of chloride and sulphate ions decreased in both CS and PGBS concrete after 90 days of curing. Sodium ions ingression also decreased after 180 days of curing. Microstructure studies were carried out using scanning electron microscope (SEM) which showed the dense formation of C–S–H gel in the matrix and high amount of Ca and Si ions in CS and PGBS concrete was observed using energy-dispersive spectroscopy (EDS) analysis. The basic properties like particle size and water absorption of CS and PGBS aggregates have majorly contributed in the reduction in voids in concrete. PGBS concrete has found to be an effective alternative in terms of performance, cost, availability, and environmentally friendly when compared to already exiting CS aggregates and NFA. © 2021, The Institution of Engineers (India).Item Stabilized Lithomargic Soil Subgrades for Low Volume Road Design Using Industrial Wastes(Springer, 2024) Marathe, S.; Bhat, A.K.; Ashmitha, N.M.; Akarsh, P.K.Lithomargic soil is considered a major group of “residual soil” which is identified as a problematic soil in the coastline region of Karnataka state of India. Previous studies reveal that the soil will cause several serious pavement deterioration problems when used as a pavement material. The present study focuses on the stabilization of this problematic shedi soil to make it suitable as a pavement subgrade material using fly ash (FA) and copper slag (CS) additives as stabilizers. In this investigation, various geotechnical properties were investigated to study the improvements in the mechanical soil properties with different percentages of FA and CS additions. For this investigation, relevant Indian standard (IS) codal guidelines were used. Initially, the effect of CS is studied by adding the various trial dosages of the CS from 0 to 50% (by weight) to the soil. The unconfined compressive strength (UCS) test revealed that the soil sample with 25% of CS has shown satisfactory results. Further, by maintaining the 25% CS dosage as constant, the FA dosage was introduced at an increment interval of 2% (by weight). The IS light compaction and UCS results revealed that a 6% dosage of FA had led to maximum strength gain. The improved mechanical performance includes an improvement in standard maximum proctor density from 15.22 to 18.16 kN/m3, soaked CBR value from 2.40 to 10.51%, and UCS value from 93 to 312 kPa. Further, the developments in the UCS and california bearing ratio (CBR) were studied by subjecting the virgin and modified soil to sustained desiccator curing at different intervals up to 56 days, the corresponding results indicated a strength gain of about 22% for the modified lithomargic soil. The durability tests were performed by subjecting the UCS specimens to alternate wetting–drying conditions and alternate freezing–thawing cycles. The test results were compared with that of the un-modified shedi soil. The test results were satisfactory for the application as the pavement subgrade material. The pavement design for the low-volume roads has been carried out using IRC: SP-72 guidelines and the pavement analysis is carried out using KENPAVE software. The results indicate that the use of 25% of CS along with 6% of FA in lithomargic soil could lead to a reduction of 46.15% of design pavement thickness and a reduced maximum deflection value upon stabilization. © The Author(s), under exclusive licence to Chinese Society of Pavement Engineering 2023.Item Microstructural insights of geopolymer mortar using binary blended sustainable fine aggregates(Elsevier Ltd, 2025) Clement, D.; C, R.; Agarwal, S.; Pratap, M.The socio-economic growth of a nation depends heavily on the availability of adequate infrastructure, which relies on essential materials like river sand (RS) and cement. However, the rising demand for RS, combined with its excessive extraction causing ecological damage, and its increasing cost, has raised significant concerns. At the same time, the production of cement contributes significantly to environmental damage, especially through CO2 emissions. In this scenario geopolymer technology has emerged as a sustainable alternative to cement, offering environmental benefits and reducing the carbon footprint of construction materials. This study investigates the impact of replacing RS with copper slag (CS) and laterite soil (LS) in geopolymer mortar (GM) on key properties such as setting time, flowability, compressive strength, and microstructure. The results showed that as LS content increased, setting time and flowability decreased considerably, while increasing CS content caused a reduction in these values. Unlike the other observed parameters, the compressive strength values showed no distinct upward or downward trend. Moreover, the microstructural analysis, including SEM, EDS, XRD, FTIR, TGA and BET, provided valuable insights to support the observed results across various mix designs. Overall, the findings highlight that optimised binary blends of CS, LS and RS not only improved the compressive strength but also enhanced the microstructural characteristics of geopolymer mortar, reinforcing their potential as sustainable and high-performance alternatives to conventional fine aggregates. © 2025 The Authors