Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
3 results
Search Results
Item 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.Item Assessment of thermally deteriorated concrete by drilling resistance test and sound level(Maik Nauka Publishing / Springer SBM compmg@maik.ru, 2017) Kulkarni, K.S.; Yaragal, S.C.; Babu Narayan, K.S.; Vardhan, H.Concrete being the most versatile and widely used construction material finds application in varied range of structures. Many of these like chimneys, furnaces and reactors have to sustain high temperatures and perhaps all structures have to perform at elevated temperatures in the event of fire accidents. Concrete at elevated temperatures undergoes changes in its physical structure and chemical composition and loses its strength characteristics. Need for quick assessment of fire damaged concrete for strength characteristics, has motivated this work, which explores the potential of drilling resistance test on concrete as a Non Destructive Testing (NDT) tool. Drilling times, penetration depths and sound level measurement while drilling have been recorded and analysed to provide monograms that are handy as reckoners in failure forensics. © 2017, Pleiades Publishing, Ltd.Item Core recovery: a damage diagnosis tool for thermally deteriorated concrete(Emerald Group Holdings Ltd., 2019) Kulkarni, K.S.; Yaragal, S.C.; S.k, B.N.Purpose: This paper aims to study and assess residual strengths of concrete specimen exposed to elevated temperatures by core recovery tests. Design/methodology/approach: The appraisal of concrete structures is typically carried out by means of partially destructive tests such as tests on concrete cores taken from the structure and non-destructive testing. Findings: This paper presents results associated with determination of residual compressive strengths of plain and reinforced concrete elements exposed to elevated temperatures by core recovery test. Physical observations and results of compressive strengths of cores extracted from plain cement concrete, as well as from reinforced concrete beam elements exposed to elevated temperatures, have been presented. Originality/value: The empirical relations have been proposed between standard cube and core extracted for compressive strength of concretes exposed to elevated temperatures are useful for damage diagnosis. © 2019, Emerald Publishing Limited.