Faculty Publications
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Item Studies on iron tailings towards usage for paving blocks manufacture(2010) Mangalpady, M.; Sampath Kumar, N.N.Disposal of mill tailings is one of the major problems in mining industry. Investigations are being done all over the world to utilize tailings for useful purposes. The scope of this work is to study the utilization of iron ore tailings in manufacture of concrete paving blocks. Five reference mixes were prepared using cement, jelly dust and baby jelly. Ten paving blocks were prepared from each type of mix, out of which five specimens were cured for 7 days and five were cured for 28 days. By using sand and tailings as fine aggregates, two modified mixes were prepared by replacing jelly dust partly in reference mixes. Similar to reference mix, five mix ratios were made and ten paving blocks were prepared from each type of mixtures. From each set of paving blocks, five specimens were cured for 7 days and the other five specimens were cured for 28 days. Laboratory tests were conducted to assess water absorption and compressive strength of specimens, and graphs were plotted for their comparison among each type of respective mix ratios. In all the comparisons, compressive strength of tailing based mix was higher than the respective reference mix. Similar trend is shown by the graphs plotted for water absorption. © 2010 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Portable low cost drill set-up for estimating rock properties(CAFET INNOVA Technical Society cafetinnova@gmail.com 1-2-18/103, Mohini Mansion, Gagan Mahal Road, Domalguda, Hyderabad 500029, 2014) Masood; Vardhan, H.; Mangalpady, M.The mechanical strength of rock is one of the most important factors of concern to engineers involved in mining operations. Information about rock strength is used in rock excavation planning and design operations in civil and mining engineering. Drilling is widely carried out in hard rock’s for blasting the rock mass so that the blasted material can be easily loaded by the excavators. The drillability of rock depends on many factors including rock properties. Whereas properties such as compressive strength, porosity, density etc. are uncontrollable parameters during drilling process. A number of studies have been reported recently on the application of sound level, which have been concentrated on using either CNC or jack hammer machine for drilling purpose. It is worth mentioning that neither CNC machine nor jack hammer drill set-up is the normal way of drilling in rock, nor in mining, civil or any other operations, not even in working with rock in installation of countertops. Therefore, it is difficult to exactly say whether the noise generated during drilling is only from the rock drilling or from the drilling unit itself. In view of the above, it is important to fabricate a new drilling set-up which is a silent unit in itself. Such unit when used for drilling purpose will clearly indicate the change in sound level produced with different rock properties. © 2014 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Investigating the Utility of Iron Ore Waste in Preparing Non-fired Bricks(Springer India sanjiv.goswami@springer.co.in, 2017) Lamani, S.R.; Mangalpady, M.; Vardhan, H.Iron ore waste is a major problem for mine owners due to the difficulty involved in its storage, handling and other environmental related issues. An alternative solution to this is utilisation of iron ore waste (IOW) as some value added product in construction industry. An attempt has been made in this paper in examining the possibility of making non-fired bricks from iron ore waste with some additives like cement and fly-ash. Each of the additives were mixed with IOW in different ratios and different sets of bricks were prepared. The prepared IOW bricks were cured for 7, 14, 21 and 28 days and their respective compressive strength and percentage of water absorption were determined. The results show that IOW bricks prepared with 9% and above cement and with 28 days of curing are suitable for brick making and meet the IS specifications. It was also observed that the weight of the prepared bricks with 9% cement with 28 days of curing varies between 2.35 and 2.45 kg whereas the weight of compressed fire clay bricks varies from 2.80 to 2.89 kg. Results also show that the cost of bricks prepared with cement ranging from 9 to 20% is comparable to that of commercially available compressed bricks. © 2016, The Institution of Engineers (India).Item Physicomechanical Properties and Characterization of Gold Ore Tailings and the Utilization in Manufacturing of Geopolymer Concrete with Class F Fly Ash and Recycled Coarse Aggregates(American Society of Civil Engineers (ASCE), 2023) Lokesha, E.B.; Mangalpady, M.; Kumar Reddy, S.K.; Srinivasa, A.S.The mining industry generates a large amount of waste, particularly in the form of tailing dumps, which creates major environmental difficulties such as air pollution, water pollution, soil erosion, and acid mine drainage. Previous studies confirmed that the mine waste could be used in making building materials, such as bricks, tiles, concrete blocks, pavement blocks, and precast concrete elements. However, gold ore tailings (GOTs) are recognized as major mine residues in the mining industry. In this study, GOTs were utilized as partial replacement material (0%, 5%, 10%, 15%, 20%, 25%, and 30% by weight) to fine aggregates such as river sand (RS) and low calcium fly ash (FA) as binder material in the manufacture of geopolymer concrete (GPC) along with recycled coarse aggregates. The GPC samples were cast and cured at room temperature until the curing ages; subsequently, the compressive strength of the samples was determined. This study demonstrated that the RS can be partially substituted in the manufacture of GPC by GOTs up to 15% with a slump value of 38.6 mm and the maximum compressive strength of 35.8 MPa. The mineralogical and chemical composition of raw materials (i.e., GOTs and FA) was analyzed using X-ray diffraction (XRD) and X-ray fluorescence (XRF), respectively. The XRD analysis revealed that the quartz has the highest peak intensity of 55% in GOTs and 50% of corundum in FA. The XRF analysis exhibited that GOTs and FA have high silicon oxides up to 39% and 38%, respectively. The crushed GPC samples were analyzed using field emission scanning electron microscopy to observe the morphological changes. The GPC sample comprised 15% GOTs exhibited denser and compacted microstructures. © 2023 American Society of Civil Engineers.Item Development of Regression Model and Optimization of Mechanical Properties of Geopolymer Concrete Prepared Using Gold Ore Tailings(American Society of Civil Engineers (ASCE), 2023) Lokesha, E.B.; Mangalpady, M.; Kumar Reddy, S.K.; Srinivasa, A.S.In this study, 11 mix proportions of geopolymer concrete (GPC) beam and cylinder samples were prepared by partially replacing the class F fly ash (FA) as the binder with ground granulated blast furnace slag (GGBFS) in steps from 10% to 100%, along with gold ore tailings (GOTs) [as a partial substitute to the river sand (RS) in steps from 5% to 30%] and recycled coarse aggregates (RCAs). The laboratory tests demonstrated a maximum split tensile strength of 5.99 MPa and flexural strength of 7.98 MPa for Sample GOT-11-15 (11 indicates Mix Proportion-XI and 15 indicates 15% of GOTs) of Mix Proportion-XI. In addition to the previous 11 mix proportions, one more set of cylinders and beams was prepared using FA, GOTs, and natural coarse aggregates (NCAs), which are designated as Mix Proportion-XII. For Mix Proportion-XII, the highest split tensile strength of 4.17 MPa and flexural strength of 6.13 MPa was achieved for Sample GOT-15 (15 indicates 15% of GOTs). Among the 12 types of mix proportions, Sample GOT-0 of Mix Proportion-XII (i.e., FA 100%, GOT 0%, and NCAs 100%) showed a maximum slump value of 89.3 mm. Sample GOT-1-0 of Mix Proportion-I (i.e., FA 100%, GOT 0%, and RCA 100%) exhibited the maximum slump of 65.3 mm. The field emission scanning electron microscopy (FESEM) analysis indicated that silicon (Si) and aluminum (Al) were the two main constituents of the GOTs and FA. In addition, this analysis revealed the existence of uneven forms of quartz particles in GOTs and the spherical shapes of the FA particles that adhered to the RCAs. The multiple regression analysis exhibited the root mean square (R2) values of 89.0% and 85.5%, respectively, for the split tensile and flexural strengths. The p-value for the developed model was <0.05; therefore, the developed model was considered significant and the best-fit model. © 2023 American Society of Civil Engineers.