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Item Investigations on compatibility of cement-superplasticizer interaction and its influence on mortar workability incorporating copper slag as fine aggregate(Institute of Physics Publishing helen.craven@iop.org, 2018) Arpitha, D.; C, C.; Puttaswamy, N.Interaction between cement and water is a complex phenomenon to understand. Sometimes achieving the desired results is quite challenging due to the contrast spotted in the characteristics of cement, type and dosage of superplasticizers (S.P) as the behaviour is insignificant. Influence of different types of cement fineness on pastes with different superplasticizers which represents the compatibility between cement with water reducing admixture in order to obtain well-defined saturation dosage and with the partial replacement of fine aggregates (F.A) by copper slag (C.S) to study the mortar behaviour is focused in this work. A methodology based on fundamental properties of cementitious systems using marsh cone and mini-slump cone tests results to identify the suitable and compatible combinations between cement and superplasticizers for the enhancement of flow behaviour of mortar mixes. © Published under licence by IOP Publishing Ltd.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 Assessment on performance of steel slag and processed granulated blast furnace slag as an alternative for fine aggregate—an assertive review(Springer Science and Business Media Deutschland GmbH, 2021) Sudarshan, V.J.; Arpitha, D.; Thilak Kumar, Y.T.; C, C.; Puttaswamy, N.Sand has always been an integral part of construction in our civilization. It has been the most easily available and acceptable source for the same. However, the depletion of river sand availability has started looking at the alternatives including some industrial by-products. One of them is slag obtained from manufacture/refining of metals which would help in the utilization of industrial waste and conservation of natural resources to have a sustainable construction. This paper provides the gist of organized overview involving the evaluation of physical and chemical characteristics, assessment of mechanical and durability properties for the effective utilization of steel slag and processed granulated blast furnace slag (PGBS) that could be modelled from previous researches related to the study. The basic properties of steel slag and PGBS exhibit requisite properties like river sand which is an indication for a possible alternative material to the conventional aggregate. The multiple processing of slag has its influence on strength, durability, and workability of concrete. These recent innovations have made the slag economically viable and environmentally friendly, and also profitable salvaging of processed by-product. © 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 Influence of Superplasticizers on Blended Cement and Their Effect on Flow Characteristics by Incorporating PGBS as Partial Replacement for Fine Aggregates(Springer Science and Business Media Deutschland GmbH, 2021) Arpitha, D.; Sudarshan, V.J.; Thilak Kumar, Y.T.; C, C.Currently the upsurge practice of the mineral admixtures as an alternative for cement to cut down the carbonic gas emission, to reduce the cement cost, and to progress some technical recitals is truly the indispensable novelty advanced in construction industry. Mortars with different w/c require the use of appropriate and compatible chemical admixtures to achieve desirable consistency. The principal tactic delivered to contest in contradiction to this exertion is to choose the furthermost effective twosome cement–superplasticizer, facilitating to attain a determined water reduction, an enhanced flow, and an adequate rheology. Processed Granulated Blast Furnace Slag (PGBS) incorporated as partial replacement for Fine Aggregates (FA) along with different types of Superplasticizers (SP) for different dosages, which were chemically based on Lignosulfonate (LS), Sulphonated Naphtha Formaldehyde (SNF), and Polycarboxylate Ether (PCE), was used to check the behavior of flow characteristics in this work. The fusion of Portland pozzolana cement (PPC) along with partial replacement of fine aggregates has resulted to understand the better flow interaction between the cementitious materials and under different water–cement ratio (w/c). © 2021, Springer Nature Singapore Pte Ltd.Item Investigations on Flow Characteristics of Mortars Using Partial Replacement of Fine Aggregates with Processed Granulated Blast Furnace Slag(Springer Science and Business Media Deutschland GmbH, 2021) Sudarshan, V.J.; Arpitha, D.; Thilak Kumar, Y.T.; C, C.; Puttaswamy, N.Sand has always been an integral part of construction in our civilization. It has been the most easily available and acceptable source for the same. However, the depletion of river sand availability has led us to start looking at the alternatives including some industrial by-products. Processed Granulated Blast Furnace Slag (PGBS) is an alternative slag sand for fine aggregate which is being extensively utilized. Low density and strength issues concerned with Granulated Blast Furnace Slag (GBS) have led to the innovation of PGBS. PGBS is considered as an economically viable and environmentally acceptable alternative material for replacing river sand having tremendous economic impact, conservation of natural resources, and gainful recycling of process by-products. In this study, mini slump cone test is conducted for mortars using 10, 20, 30, and 40% partial replacement of Fine Aggregates (FA) (River sand) with PGBS to study the flow behavior and to identify the suitable combinations of water binder ratio (W/B) (0.4, 0.45, and 0.5) and superplasticizer dosage (0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, and 2.0). © 2021, Springer Nature Singapore Pte Ltd.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 Study on Processed Granulated Blast Furnace Slag as a Replacement for Fine Aggregates for the Greener Global Construction(Springer Science and Business Media Deutschland GmbH, 2023) Arpitha, D.; C, C.; Kappadi, P.As innovation in concrete technology advances and the environment weakens, it is currently evident that the boundless utilization of construction materials and its initial expense being the common determination model has become a routine with regard to the past. Since there is great interest for raw materials and natural resources are rare, it is expected to utilize a high volume of alternative materials in concrete that would be monetarily beneficial like crushed sand, blast furnace slag, etc. An experimental investigation was carried out to examine the behaviour of mortars incorporating partial volumes of secondary material to fine aggregates. Processed granulated blast furnace slag (PGBS), newly processed slag which had overcome the limitations of granulated blast furnace slag obtained as a by-product during the extraction of steel was tested for fine aggregate (FA) replacement. Several combinations of mortar mixes were prepared using Lignosulfonate (LS), Sulphonated Naphthalene Formaldehyde (SNF) and Polycarboxylate Ether (PCE)-based superplasticizers (SP) for 0 and 50% replacement levels of FA by PGBS to recognize the feasible optimum dosage of SP required to achieve desired flow characteristics of mortars. Based on the optimum dosage of SP and w/c obtained, mortar cubes were prepared and cured for 3, 7, and 28 days. These cubes were tested for compressive strength periodically, the results revealed that PCE-based SP exhibited better performance concerning flow behaviour and strength gain parameters along with the effective reduction in w/c for both 0 and 50% FA replaced mixes. PGBS exhibited higher strength when compared to 0% replaced mixes though there was a slight increase in water content required for the cohesive mix. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Item Suitability study of processed granulated blast furnace slag (PGBS) as fine aggregate replacement in mortar exposed to the marine environment(Elsevier Ltd, 2023) Salihi, A.; Arpitha, D.; C, C.With the increasing demand for infrastructures and other buildings in all over the world the demand for natural sand as fine aggregates is growing. Various parts of the world are facing an acute shortage of natural aggregate. Despite that, every year, millions of tons of industrial waste are being produced and dumped, which is a good alternative for natural aggregate. This paper is mainly about the partial replacement of advanced and processed form of GBS (generated in steel plants) call as PGBS (Processed Granulated Blast Furnace Slag) which has similar properties as natural sand, as fine aggregate (FA) and to find out the effects on mortar mixes exposed to the marine environment. Mortar cubes and prisms were prepared with the following percentages of PGBS (10%, 30%, 50%) compared to normal mixes (0%). The specimens were exposed to the marine environment and normal water conditions. Harden properties like compressive strength and drying shrinkage of mortar were observed for 7, 14, 28 and 90 days. The study mainly focused on drying shrinkage, which is a significant issue in today's concrete industries. The study finds out that drying shrinkage and compressive strength properties of mortar improved by an increase in the percentage of PGBS and recommends suitable use of PGBS in mortar mixes. © 2023 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).