• Eadara Ramesh Babu

The effect of thermal stresses and deformations on the performance of structure due to increase in temperaturehas been studied by experimental investigations carried out on the behavior of self-compaction Concrete Filled Steel Tube (CFST) under cyclic loading at elevated temperatures. The raise in temperature due to fire causes the structural elements to expand and if the expansion is restrained, the internal stresses are introduced which intern effects the expectedload carrying capacity of the structure also results in decrease of stiffness and strength which significantly influences the structural performance. The study includes experimental investigation on a total of 128 specimens that includes 32 specimens of hollow and 96 specimens filled with SCC of grades M20, M30, and M40. The various parameters such as geometry of the specimen – circular section, different L/D ratios, and different grades of self-compaction concrete infill have been selected. The specimens including four L/D ratios and having 33.7 mm outer diameter andconstant thickness 3.2 mm,whichweresubjectedtodifferentelevatedtemperature(i.e.,30°C. 60°C,90°C,120°C, 150°C, 180°C, 200°C and 300°C) and tested. The experimental column strengths are compared with values obtained by Euro code -4. The experimental results indicates that with increase in temperature, the load carrying capacity of CFST decreases. The ultimate load carrying capacity is higher for SCC filled tubes than the hollow tubes and higher for higher grade ofSCC. The required mathematical formula has been proposed to reduce the variation of experimental results in comparison with Euro code-4 formula.

CFST, cyclic loading, elevated temperature, self-compactionconcrete,buckling load

"EXPERIMENTAL INVESTIGATION ON CFST COLUMNS UNDER CYCLIC LOADING SUBJECTED TO ELEVATED TEMPERATURE", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.5, Issue 8, page no.986-992, August-2018, Available :http://www.jetir.org/papers/JETIR1808294.pdf

"EXPERIMENTAL INVESTIGATION ON CFST COLUMNS UNDER CYCLIC LOADING SUBJECTED TO ELEVATED TEMPERATURE", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.5, Issue 8, page no. pp986-992, August-2018, Available at : http://www.jetir.org/papers/JETIR1808294.pdf