Faculty Publications
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Item Corrosion Characteristics of Metal Matrix Composites(Elsevier, 2021) Bhat Panemangalore, D.; Bhat K, U.To tackle significant challenges posed by industries and environment with respect to materials degradation, we need to have a clear understanding of the impact of corrosion in different components. Composites are designed for a specialized application using different material combinations. This article presents an overview on different corrosion characteristics of metal matrix composites. Several types of corrosion have been addressed along with different corrosion methodologies. Corrosion of aluminum MMCs, magnesium MMCs, etc., have been discussed, along with different processing related problems. Different aspects involved in determining the corrosion behavior of metal matrix composites have been addressed. © 2021 Elsevier Ltd. All rights reserved.Item Microstructural Aspects of Metal-Matrix Composites(Elsevier, 2021) Bhat Panemangalore, D.B.; Shabadi, R.Microstructures play a very important role in deciding the end properties of an alloy or a composite. Optimized microstructure could be obtained by a careful choice of processing technique and selection of materials. Metal-matrix composites (MMCs) that have been developed significantly over the last five decades possess valuable properties. MMCs can be tailored with myriad of variations to suit for a particular application and hence they belong to a unique class of materials. However, it is important to understand the microstructural aspects to understand the behavior of the component in different environmental and working conditions. This article presents an overview on different microstructural aspects of metal matrix composites. © 2021 Elsevier Ltd. All rights reserved.Item Numerical Study on Bearing Capacity Estimation of Circular Footing on Sand Reinforced with Sisal Geotextile(Springer Science and Business Media Deutschland GmbH, 2025) Jena, S.; Khatri, V.N.; Nainegali, L.This paper presents a study on estimating the bearing capacity of shallow circular footings on sand. In this regard, finite element analysis is conducted, assuming that the sand follows Bolton’s model with a relative density of 75%. Initially, the bearing capacity is determined for unreinforced sand conditions, followed by the placement of geotextile at different depths. The results indicate a significant increase in the ultimate bearing capacity of the footing, up to 2.68 times, compared to the unreinforced case, precisely when the geotextile is placed at a depth of 0.25 times the footing diameter. These findings suggest that sisal geotextile can effectively serve as a reinforcement material for addressing various temporary foundation-related problems. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.Item With a view to study the response to impacts, epoxy-fly ash systems, with filler particles treated with silane material to their surface were fabricated. The test coupons made from the cured thermoset cast slabs were subjected to impact in an instrumented test set up, where, provision existed for recording both load and total energy absorbed with respect to time. The investigation shows that the crack path shift was highest for unreinforced ones, which, display river marks.(Carl Hanser Verlag, Correlating failure features to impact data in epoxy systems without and with silane surface bearing fly ash filler particles in varying amounts; Korrelation von versagensmerkmalen und schlagzähigkeitsdaten in epoxidsystemen mit und ohne silanbeschichtete flugascheteilchen in unterschiedlichen volumenanteilen) Kishore; Ravikumar, N.L.; Kulkarni, S.M.2004Item Strength behaviour of geogrid reinforced shedi soil subgrade and aggregate system(2006) Ravi Shankar, A.U.R.; Suresha, S.N.Shedi soil (Lithomargic clay), a yellowish-white silty soil underlying lateritic soil, is densely deposited along Konkan belt of India. The strength behaviour of Shedi soil under varying moisture content is major problem for road construction projects in this region. In the present investigation, the subgrade is stabilized with geogrid, keeping the geogrid at different positions from top of subgrade, to locate its optimum position. The plate load tests were also conducted at soaked and unsoaked conditions for unreinforeced, reinforced (with Geogrid) subgrade with aggregate base course. An equation has been established based on load-deflection values recorded for subgrade of un-reinforced and reinforced with geogrid at different levels. The deflection values obtained from equation and from the laboratory investigation were compared. In the case of reinforced subgrade with aggregate base course, the theoretical deflection values were computed based on Burmister's theory and compared with laboratory deflection values.Item Stone Columns with Vertical Circumferential Nails: Laboratory Model Study(2010) Shivashankar, R.; Dheerendra Babu, M.R.D.; Nayak, S.; Manjunath, R.This paper presents results from a series of laboratory plate load tests carried out in unit cell tanks to investigate the improvement in stiffness, load carrying capacity and resistance to bulging of stone columns installed in soft soils. A new method of reinforcing the stone columns with vertical nails installed along the circumference of the stone column is suggested for improving the performance of these columns. Tests were carried out with two types of loading (1) the entire area in the unit cell tank loaded, to estimate the stiffness of improved ground and (2) only the stone column loaded, to estimate the limiting axial capacity. It is found that stone columns reinforced with vertical nails along the circumference have much higher load carrying capacity and undergo lesser compression and lesser lateral bulging as compared to conventional stone columns. The benefit of vertical circumferential nails increases with increase in the diameter, number and depth of embedment of the nails. The improvement in the performance of stone column was found to be more significant, even with lower area ratio. It is found that reinforcing stone column with vertical circumferential nails at the top portion to a depth equal to three times the diameter of stone columns, will be adequate to prevent the column from excessive bulging and to improve its load carrying capacity substantially. © 2010 Springer Science+Business Media B.V.Item Performance appraisal of RC beams using welded wire fabrics as lateral reinforcement in seismic zones(CAFET INNOVA Technical Society 1-2-18/103, Mohini Mansion, Gagan Mahal Road, Domalguda, Hyderabad 500029, 2011) Gowda, H.C.C.; Babu Narayan, K.S.; Venkataramana, K.Ductility is the key to design earthquake resistant structures. More rigid the structure or the element, more it attracts inertia forces. Structures and elements of infinite rigidity are out of question. Codes of practice also advocate design philosophies wherein effects of small earthquakes are to be absorbed with little or no damage, medium with damage to such extents that rehabilitation is possible and large earthquake effects to be catered without collapse. To absorb the tremendous energies that are input to structures and elements unless ductility is ensured, performance levels proposed by codes and standard practices cannot be attained. Lateral ties hold longitudinal reinforcement of R.C.elements in place and also confine the concrete. The basis of the present work is the usage of welded wire fabrics as lateral reinforcement in RC beams. A series of beams were tested with lateral ties and welded wire fabric at discrete locations and welded wire fabric alone throughout the beam with different mesh opening sizes. This paper presents the encouraging results with marginal increase in strength and considerable improvement in ductility in addition to reduced crack widths as observed for specimens having welded wire fabric with smaller mesh openings as lateral reinforcement by confining concrete. © 2011 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Shear strengthening of unreinforced masonry walls using GFRP (glass fiber reinforcement polymer) bars(2012) Zyad, T.; Bajpai, K.K.Unreinforced masonry (URM) walls exhibits poor seismic performance under moderate and high seismic demand. The present experimental and analytical study, performed on brick masonry panels strengthened by glass fiber reinforcement polymer (GFRP) bars, was aimed to investigate the effectiveness of alternate shear reinforcement technique to reduce seismic damage. A series of three unreinforced masonry (URM) panels and three strengthened panels were subjected to diagonal compression tests according to ASTM E519. Tests were also carried out to determine compression strength of masonry prism, coefficient of friction and bond strength between masonry and mortar. Different reinforcement configurations were evaluated based on analytical studies, to come up with the most effective design for strengthening. The study pointed out that the reinforcement in the diagonal direction increases the effective bond length of the bars intersecting the diagonal crack, thus making the reinforcement design, more effective and more economical. © 2012 Cafet-Innova Technical Society.Item Accelerated consolidation of coir reinforced lithomargic laterite soil blends with vertical sand drains for pavements(2012) George, V.; Hegde, R.N.; Vardhana, M.V.; Santosh, G.; Gotamey, D.It is found that sub-grade soils of lateritic origin encountered in the construction of highway embankments in various regions of India, often comprise intrusions of soft lithomargic soils that result in large settlements during constructions, and differential settlements at later stages. This necessitates the use of appropriate soil improvement techniques to improve the load-carrying capacity of pavements. This work deals with the accelerated consolidation of un-reinforced and coir-reinforced laterite and blended lithomargic soils, provided with three vertical sand drains. The load-settlement characteristics were studied for various preloads ranging from 50kg (0.0013 N/mm2) to 500kg (0.013N/mm2). Studies were performed using circular ferro-cement moulds. It was observed that at lower preloads of up to 250kg, the relative increase in consolidation (Rct) for randomly reinforced soil with vertical drains was significantly higher than that of un-reinforced soil without vertical drains. Also, the Rct for un-reinforced soil with vertical drains was quite higher than that of un-reinforced soil without vertical drains, with an average value of 20.84%. In the case of higher preloads the Rct values for randomly reinforced soil with vertical drains were moderate with an average value of 22.67%. An additional increase of up to 27% at lower pre-loads and 11.83% at higher pre-loads was observed due to the effect of random reinforcement when compared to use of vertical drains alone. © 2012 ejge.