Faculty Publications
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Item Experimental Studies on Self-Compacting Alkali Activated Slag Concrete Mixes Incorporating Reclaimed Asphalt Pavement as Fine Aggregate(Trans Tech Publications Ltd, 2023) Joy, A.; Manjunath, R.; Neha, S.N.; Prashanth, M.H.Here performance evaluation of Self Compacting Alkali Activated Slag Concrete incorporating Reclaimed Asphalt Pavement as fine aggregate was carried out. Investigation on mechanical properties by replacing the fine aggregate by Reclaimed Asphalt Pavement in different proportions were also evaluated. Development of Self Compacting Alkali Activated Concrete mixes (SCAAC) was made with GGBFS and Lime are used binders, with binder content varying between 550 to 650 kg/m3 of fresh concrete and lime content varying from 10% to 20% of binder content. The net W/B ratio of the mixes was kept around 0.57. The fine aggregate was replaced by Reclaimed Asphalt Pavement with percentage replacement from 50 to 100% of Crushed Stone Sand. The alkaline solutions had Na2O dosage percentages in the range 5-6% with a constant activator modulus maintained at 1. By using Minitab Statistical Software nine mixes were produced with 4 factors and 3 levels. In this study the TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) optimization technique was carried out to know the effectiveness. Results showed the slump flow greater than 650 mm, with their L–Box, U-box and V-Funnel values ranging between 0.85,20mm and10s respectively, results showed enhanced mechanical properties as compared to control OPCC mix. © 2023 Trans Tech Publications Ltd, All Rights Reserved.Item Numerical Modeling of Geopolymer Concrete Short Columns Reinforced with GFRP Bars Under Different Loading Conditions(Springer Science+Business Media, 2025) Guruprasad, T.N.; Prashanth, M.H.; Narasimhan, M.C.; Manjunath, L.Infrastructure developments are on the increase all around the world. Building these modern infrastructural facilities requires large amounts of steel and concrete. India is one of the world's largest producers of steel and cement. However, to produce one ton each of steel and cement, 1.85 tons and one ton, respectively, of CO2 is released into the environment, contributing immensely to global warming. Again, embedded steel bar corrosion is the main threat to the durability of the reinforced concrete elements. So, Glass fiber-reinforced polymer bars and geopolymer concrete can be employed in RC elements, like columns, for enhanced sustainability. A sustainable and green alternative to OPC concrete is geopolymer concrete (GPC), which uses waste residues such as GGBS, flyash, and aggregates to prevent extraction of raw materials and reduce demand for disposal of waste. The current investigation aims to find the effectiveness of using short geopolymer concrete columns reinforced with GFRP bars. The present study performs a 3D finite element analysis over geopolymer concrete-based short columns with GFRP bars. A representative with a total 1200 mm height and 160 mm × 260 mm cross-section is considered for the GFRP bars reinforced columns under different conditions of loading. Results of FEA analysis carried out using the commercial ANSYS software show that reinforcing the RC short columns with GFRP bars is effective in that they exhibit 10% more buckling strength and 40% more in compression under concentric loading as compared to eccentric loading and also the deformation in the eccentrically loaded column is 50% more when compared to concentrically loaded GFRP RC short column. © 2025 The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG.Item Experimental and numerical studies on compressive behaviour of CFRP wrapped cylindrical concrete specimens subjected to different pre-loading conditions(Elsevier Ltd, 2020) Sathwik, M.C.; Prashanth, M.H.; Naik, S.C.; Satish, A.Numerous concrete structures have reached the end of their service life, either due to deterioration of the concrete caused by environmental factors or due to being functionally obsolete. Most of them are in serious need for restoration, retrofitting and rehabilitation. Carbon fibre reinforced polymer sheets are well suited for this because of their high strength to weight ratio, good fatigue properties and excellent resistance to corrosion. Their application has been rapidly growing in the civil engineering field and is becoming a promising solution for strengthening the deteriorated structures. Since CFRPs are easy to apply, they minimize labour costs and leads to significant savings in the overall costs of the project. In the present study, concrete specimens were damaged to a different extent by subjecting it to uniaxial compression followed by wrapping with CFRP sheets. Then, the effects of CFRP wrapping on the strength of pre-damaged concrete specimens are studied experimentally. Thereby the behaviour of normal concrete and CFRP wrapped concrete specimens are studied. The experimental results obtained are compared with the numerical results obtained using ABAQUS software. © 2019 Elsevier Ltd. All rights reserved.Item Analysis of anchorage zone stresses in post-tensioned concrete girders(Springer Science and Business Media Deutschland GmbH, 2021) Dipindas, C.D.; Prashanth, M.H.; Lakshmy, P.Application of pre-stressed concrete for the construction of civil engineering structures especially bridges has increased tremendously. In the pre-stressed post-tensioned concrete structures, anchorage zone is the critical area of concrete ahead of the anchorage device. During application and diffusion of the pre-stressing force in a post-tensioned girder, tensile bursting stresses are developed at some distance ahead of the anchorage device in a region known as the general zone. These stresses often lead to serviceability problems and congestion of reinforcement at the anchorage zone. In this paper, a rectangular end block of 600 × 600 mm, with a bearing plate size of 214 × 214 mm, subjected to a concrete pre-stressing force of 2204 kN was analysed using the methods like elastic method, deep beam analogy, strut-and-tie model approach, finite element analysis and also using the codal provisions specified in IRC: 18 and British code BS: 8110. From the analysis of 2D finite analysis, it was observed that the variation of bursting stress in the end block is parabolic in nature. It was observed that with increase in eccentricity of bearing plate, there was a decrease in bursting tensile stress, whereas the value of spalling tensile stresses increases drastically. However, with increase in the size of the bearing plate, both the spalling and bursting stresses decrease considerably. It was also found that the grade of concrete has negligible effect on the distribution which is of bursting tensile stress. The finite element analysis of anchorage zone with multiple anchors indicates that spalling stresses are more critical than the bursting stresses for the design of anchorage zone. © Springer Nature Singapore Pte Ltd 2021.Item Deflection Surface Analysis of Thin Plate Structures Using Regression Technique(Springer Science and Business Media Deutschland GmbH, 2023) Singh, V.; Prashanth, M.H.Deflection analysis of any structure is of common interest while designing the structure. Analysis for deflection in thin plate structures is generally done with the help of Kirchhoff’s plate theory, also known as classical plate theory. Kirchhoff’s plate theory helps in developing a fourth-order partial deflection equation relating the deflection of a plate to the loading condition on the plate and the material or bending rigidity of the plate. The present study focuses on the analysis of a simply supported thin concrete plate that is subject to uniform loading over the entire plate area. The deflection surface of the plate is developed using Navier’s double trigonometric Fourier series. Regression analysis is done to understand how various plate parameters like material rigidity, loading on the plate, and area of the plate could affect the magnitude of deflection of the plate. Also, the effect of the mentioned plate parameters on the magnitude of bending moments, twisting moments, and shear forces acting on the plate is studied. Regression modelling is used to achieve the same. Statistical metrics like R-squared error, Root Mean Square Error (RMSE), and Mean Absolute Percentage Error (MAPE) are used to check the efficiency of regression analysis. In the present study, the regression modelling technique is also used to solve the fourth-order partial differential equation. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.Item Study on the effectiveness of prefabricated cage system reinforcement in columns(Institute of Physics, 2023) Thejarathnam, T.; Prashanth, M.H.; Kuttagola, I.The concrete is the primary vertical load bearing component in a reinforced concrete column whereas the steel cage provides additional vertical load carrying capacity along with the confinement of core concrete. The research paper will focus on the performance of Prefabricated Cage System (PCS) Reinforcement in square columns. Eight columns were casted and tested, out of which two are rebar reinforced columns and six are PCS reinforced columns. There were two test groups, each group containing one rebar column and three PCS columns. In this study work is done to compare the performance of a PCS reinforced column to a rebar reinforced column, in addition comparing PCS cages of differently sized grid openings. The objective is to theoretically, experimentally, and numerically investigate the PCS column for its load carrying capacity and displacement capacity. From the results it is observed that as the size of opening of a PCS reinforced column increase, the load carrying capacity increases as the concrete running through the openings can strengthen the connection. Hence to improve the effectiveness of the PCS columns the spacing of openings should be increased. Further, the stiffness and energy absorption are more in rebar reinforced column compared to all PCS columns. © Published under licence by IOP Publishing Ltd.Item Numerical investigation of the hybrid reinforced concrete beam using GFRP bars(Institute of Physics, 2023) Kumar, A.; Prashanth, M.H.; Kuttagola, I.The numerical study of the hybrid reinforced concrete beam using GFRP bars has been explored in this research. Finite element software ABAQUS had been used for numerical investigation. In the present research, the use of GFRP bars as a replacement to steel reinforcing bars for longitudinal reinforcement is attempted. Further, a RC beam by using GFRP as longitudinal reinforcement and steel rebars as transverse reinforcement is compared with the conventional steel reinforced concrete beam. The beams are tested for three-point bending using numerical simulation under displacement control. By performing the numerical modelling, load, strain and displacement data has been attained. Further, by using the output data, stress-strain curves of concrete, load versus strain variations in tension bars and load versus deflection curves are plotted. The stresses, deflections, strain developed in longitudinal bars, load carrying capacity, energy absorption are then calculated using the data and are compared. From the results it is observed that, the load carrying capacity decreases by 16% and the energy absorption increases by 29% when longitudinal steel bars are replaced by GFRP bars. © Published under licence by IOP Publishing Ltd.Item Numerical study on the behavior of RC beams by using GFRP bars as an alternate to steel bars(Elsevier Ltd, 2023) Kuttagola, I.; Prashanth, M.H.; Kumar, A.The numerical study of the behavior of reinforced concrete beams by using Glass fiber reinforced polymer (GFRP) bars as an alternate to steel bars has been explored in this research. The numerical modelling of the beams is done using Finite element analysis (FEA) software ABAQUS. In the present study the beam with Glass fiber reinforced polymer (GFRP) bars as both longitudinal & transverse reinforcement is compared with conventional reinforced concrete beam. The numerical simulation is performed for three-point bending for displacement control. The results of load, strain and deflection data has been obtained from the numerical modelling. Stress versus strain curves, load versus strain curves and load versus deflection curves are plotted using the output data. The displacement, strain developed in longitudinal bars and stirrups, load carrying capacity, energy absorbed are then calculated using the data and are compared. From the results, it is observed that the Glass fiber reinforced polymer (GFRP) reinforced concrete beams have load carrying capacity par with conventional reinforced concrete beam. Further, Glass fiber reinforced polymer (GFRP) reinforced concrete beams have higher yield strains and experienced more energy absorption over conventional reinforced concrete beam. © 2023 Elsevier Ltd. All rights reserved.Item Numerical study on fracture behavior of alkali activated concrete mixes for different beam sizes(Elsevier Ltd, 2023) Annappaswamy, G.M.; Channappa, T.M.; Prashanth, M.H.The present study considers the use of AAC mixes, since the raw materials that are being used to produce concrete are non-renewable natural resources, particularly Ordinary Portland Cement (OPC). Also, production of OPC contributes a greater amount of CO2 to the environment. Hence, an attempt has been made to study alternative construction materials keeping in mind sustainable development. The present numerical study compares the fracture behaviour and size effect of Alkali Activated Concrete (AAC) mixes with Ordinary Portland Cement Concrete (OPCC) mixes by numerically modelling the beams of AAC and OPCC using FEA software ABAQUS. Three different mixes of AAC, characterized by the variation of percentage volume of water-quenched slag (WQS) as a substitute for Natural sand (RS) and one OPCC mix, were studied. A three-point bending test was performed in ABAQUS for the beams of three different sizes, which are geometrically similar with constant thickness. Numerical simulation is performed under displacement control. Load versus CMOD graphs are plotted from the output data obtained from the numerical modelling. Fracture parameters such as Fracture energy (GF), Brittleness number (B), Characteristic length (lch), and Stress intensity factor (KIC) are then calculated from the obtained data and compared to understand the influence of fracture properties and size effect on the behaviour of structural elements since limited research works are available from the literature. From the results, it is observed that OPCC mixes show superior strength, high resistance to crack propagation, more toughness, and high fracture energy when compared to AAC mixes. AAC-50 concrete mix has shown better performance compared to the other two AAC mixes, i.e., AAC-0 and AAC-100. The results of this work can certainly be used to predict the non-linear behaviour of concrete and can be adopted in the design of structural elements. © 2023 Elsevier Ltd. All rights reserved.Item The load carrying capacity of reinforced concrete columns subjected to elevated temperature using simplified method(Elsevier Ltd, 2023) Akkannavar, C.; Prashanth, M.H.; Banasode, S.The present work proposes a method to determine the load-carrying capacity of the reinforced concrete column at elevated temperatures. The method uses the zone method mentioned in Eurocode to determine the temperature-dependent material properties of steel and concrete. Later the design equations, as per Indian standard guidelines, are used to determine the load-carrying capacity of the column. The loads considered here include both axial loads as well as uniaxial moments. The results obtained are validated with experimental data from the literature. Once Puand Muare determined using temperature-dependent materials properties, interaction curves are plotted at various temperatures mentioned in the standard time-temperature curve. The results obtained are validated against the experimental results from the literature. The Paper also investigates the behaviour of reinforced columns by varying design parameters like the size of the column and the grade of concrete. The work also discusses the relevancy of the 500° Isotherm method and the zone method mentioned in Eurocode when designing columns at elevated temperatures per Indian Standard guidelines. © 2023 Elsevier Ltd. All rights reserved.