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Item Partial replacement of steel slag aggregates in concrete as fine aggregates (induction blast furnace slag)(Springer, 2019) Sundaramoorthi, S.; Hemalatha, T.; C, C.In this study, an attempt has been made to investigate the effect of partial replacement of conventional river sand with steel slag aggregate. The replacement of river sand by slag aggregate provides dual advantage of reducing disposal problems in steel industries and conserving the natural resources. In this study, slag aggregate originated from induction blast furnace has been used. The physical and chemical properties of slag aggregate evidenced the feasibility of using this material as a substitute for river sand. Total of three mixes made with Ordinary Portland Cement (OPC), cement replaced with fly ash and river sand replaced with slag aggregate have been considered for this study. The mix is designed for M40 grade. First mix (Control mix 0M0) made of OPC as a binder and 100% river sand, second mix (0M50) made of OPC and 50% slag aggregate and third mix (25M50) made of 25% OPC replaced by fly ash and 50% river sand replaced by slag aggregate. Mechanical and durability properties of all the three concretes are studied. It is found that the strength results of 0M0 and 0M50 are comparable indicating the suitability of using slag aggregate as an alternative for river sand. However, the third mix with fly ash replacement in binder showed reduced strength in comparison with control concrete. Hence, it is concluded that when slag aggregate is used as a partial replacement for river sand (50%), it is advisable to use OPC than the Pozzolanic Portland Cement (PPC). © Springer Nature Singapore Pte Ltd. 2019.Item Performance of eco-friendly mortar mixes against aggressive environments(Techno-Press info@techno-press.com, 2020) Saha, S.; C, C.; Gupta, P.Past research efforts already established geopolymer as an environment-friendly alternative binder system for ordinary Portland cement (OPC) and recycled aggregate is also one of the promising alternative for natural aggregates. In this study, an effort was made to produce eco-friendly mortar mixes using geopolymer as binder and recycled fine aggregate (RFA) partially and study the resistance ability of these mortar mixes against the aggressive environments. To form the geopolymer binder, 70% fly ash, 30% ground granulated blast furnace slag (GGBS) and alkaline solution comprising of sodium silicate solution and 14M sodium hydroxide solution with a ratio of 1.5 were used. The ratio of alkaline liquid to binder (AL/B) was also considered as 0.4 and 0.6. In order to determine the resistance ability against aggressive environmental conditions, acid attack test, sulphate attack test and rapid chloride permeability test were conducted. Change in mass, change in compressive strength of the specimens after the immersion in acid/sulphate solution for a period of 28, 56, 90 and 120 days has been presented and discussed in this study. Results indicated that the incorporation of RFA leads to the reduction in compressive strength. Even though strength reduction was observed, eco-friendly mortar mixes containing geopolymer as binder and RFA as fine aggregate performed better when it was produced with AL/B ratio of 0.6. © 2020 Techno-Press, Ltd.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 EXPERIMENTAL INVESTIGATIONS ON THE PROPERTIES OF CONCRETE CONTAINING PRE-SOAKED RECYCLED FINE AGGREGATE(Associated Cement Companies Ltd., 2022) Saha, S.; C, C.; Ganiger, M.S.; Sajjan, S.Recycled fine aggregate (RFA) becomes very significant and promising alternative materials for natural fine aggregate (river sand) to be used in the production of concrete. But, most of the past research works indicated higher water absorption capacity of RFA as one of the key factor to affect the properties of fresh concrete. Therefore, an experimental attempt has been made to address the issues related to water absorption capacity of RFA by soaking it in water for 24 hours prior to use as alternative fine aggregate for the production of the fresh concrete. Mechanical properties of concrete such as compressive strength, splitting tensile strength, and flexural strength, and durability properties such as resistance against acidic and alkaline environment, chloride permeability test for ordinary Portland cement (OPC) and Portland pozzolana cement (PPC) based concrete mixes made with soaked recycled fine aggregates (SRFA) are determined, and analysed. For OPC, and PPC based concrete, respectively 4.32, and 20.75 % in compressive strength at 28 days; 2.69, and 27.24 % increase in flexural strength; 6.38, and 40 % increase in splitting tensile strength at 28 days were observed for the concrete mixes with SRFA compared to the mixes with RFA. Experimental results indicated notable improvement of the mechanical, and durability properties of concrete mixes when recycled fine aggregates were soaked in water prior to use. © 2022, Associated Cement Companies Ltd.. All rights reserved.Item PERFORMANCE ASSESSMENT OF STEEL SLAG AGGREGATES AS PARTIAL REPLACEMENT OF RIVER SAND IN CONCRETE(Associated Cement Companies Ltd., 2023) Sundaramoorthi, S.; Hemalatha, T.; C, C.In order to bring sustainability in construction, nowadays, many industrial solid wastes are used as a partial replacement for cement as well as aggregates. Using industrial wastes in construction solves dual problem of waste disposal and depletion of natural resources. Steel aggregate is one such industrial solid waste having potential to replace the conventional river sand. In this study, an attempt has been made to investigate the performance of steel slag aggregates in concrete as a partial replacement for conventional river sand. Three mixes were made for this study, first mix made of ordinary Portland cement (OPC) and 100 % river sand (0M0), second mix (0M50) made of OPC and 50 % river sand replaced by slag aggregates and third mix (25M50) made of 25 % fly ash and 75 % OPC, and 50 % slag aggregates. Tests for assessing the mechanical and durability properties were conducted. The results showed that the strength and durability of concrete made with steel slag aggregate and river sand were comparable. This study shows the suitability of using 50% steel slag aggregates as a partial replacement for river sand in concrete. © 2023, Associated Cement Companies Ltd.. All rights reserved.