Faculty Publications

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    Effect of Heating and Fluid Saturation on Certain Physico-Mechanical and Fracturing Behaviour of Concrete
    (Springer Science and Business Media Deutschland GmbH, 2024) Gafur, I.A.; Anilkumar, A.; Parappalli, A.N.; Srinivasan, V.
    Understanding the fracturing characteristics of construction materials under varying environmental conditions is very important in considering the safety of infrastructural facilities for sustainable civil structures. Concrete has been extensively used in construction, and with recent advancements in offshore structures, its strength in adverse conditions is pivotal and hence requires significant attention. This study investigates the variation in the mechanical properties and fracturing behaviour of M25 concrete cubes under different environmental conditions. The cubes were subjected to five different conditions: heating, saturation, and a combination of heating and saturation. Saturation was carried out separately using water and brine solutions. Three cubes were cast for each condition. The physical properties included density and Ultrasonic pulse velocity, followed by mechanical testing for strength. Acoustic emission monitoring was carried out simultaneously along the mechanical testing. Acoustic emission techniques are used to visualize fracturing behaviour of concrete cubes. Fracture thresholds are established to find crack closure and elastic region, and regions of stable crack propagation and unstable crack propagation. The results show that the combination of heating and fluid saturation significantly impacts the physico-mechanical properties of concrete, reducing its compressive strength and increasing its susceptibility to fracture. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.
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    Performance of hybrid fibre-reinforced concretes at elevated temperatures
    (Emerald Group Holdings Ltd., 2017) Shirsath, S.K.; Yaragal, S.C.
    Purpose – This study reports the performance of thermally deteriorated concrete with and without fibres. Attempts have been made to find the suitable performance of steel polypropylene (PP) hybrid fibre combination that could significantly enhance the performance of mechanical properties at elevated temperatures. Design/methodology/approach – In this experimental investigation, concrete cubes of 100 mm in size of various compositions were cast and water-cured for 28 days, and later exposed to elevated temperatures of either 200 or 400°C or 600 and or 800°C with a retention period of 2 h. The properties like change in colour and percentage weight loss were evaluated. Ultrasonic Pulse Velocity test was used to obtain qualitative information of strength variation. Residual strength of thermally deteriorated concrete specimen was measured by destructive testing. Findings – Steel fibre volume fraction of 1 per cent improves the compressive strength of concrete in the temperature range of 400 to 800°C. The addition of steel fibre and PP fibre (Mix 3) improves the splitting strength of the concrete at elevated temperature range of 400 to 600°C. Originality/value – Performance enhancement is observed with hybrid fibres for temperature endurance of concrete. © Emerald Publishing Limited.