Abstract: For Bangladesh fire is the single most disaster causing maximum loss of life and economy after natural disaster. To understand the effect of fire on mechanical properties and microstructure of steel re-bars, 3 different grades (500W TMT, 400, 300 grade) of locally produced bars of 8 mm diameter has been investigated. Each grade of rebar was tested at 3 different temperature (500°C, 600°C & 650°C) in steady method at a strain rate of 0.5 mm/min. Their high temperature chemical composition, mechanical properties and microstructure were determined and compared with the ones from the as received condition. The test results demonstrated all grades of local steel bars loses their mechanical properties with increasing temperature. It is to be noted that, 300 grade bar lose their strength much easily than the 500W TMT. The deterioration of mechanical properties with increased temperature was due to the tempering of steel above 560°C.
Authors: Rashidun Nawaz Shaown, Sayem Shahriar, Shubhrodev Bhowmik
Keywords:high temperature deformation, reduction factor, grades of steel rebars