The aim of this investigation is firstly to evaluate the effect of different methods used for confining the reinforced concrete (R.C) columns either internally or externally. Secondly, the effect of overheating on the performance of confining methods was conducted using the computer program “ANSYS 5.4”. Beside the traditional transverse steel ties, the internal confinement was satisfied by steel fibers or a cage of expanded metal mesh inside the ties, while external confinement was achieved by wrapping the studied columns with GFRP sheets or ferrocement layers. Six R. C columns were prepared, namely, the control column reinforced traditionally with transverse ties only, two columns containing 1% and 2% steel fibers, one column reinforced additionally with a cage of expanded metal mesh, two columns wrapped with either glass fiber reinforced plastics (GFRP) or ferrocement laminates. The columns were tested under axial loads to evaluate the effect of the different confining methods on the ultimate capacity and ductility. It was found that adding 2% steel fibers or reinforcing the column with a cage of expanded metal mesh inside the ties gave almost similar results (26% increase in the ultimate capacity compared with that of the control column). Despite that the ultimate capacity of the column wrapped with GFRP was the highest among the studied columns (36% increase in the ultimate capacity), its ductility was the lowest. The parametric study using ANSYS 5.4 showed that the R.C columns contain steel fibers were less affected by fire than the other columns. It was also found that the ultimate capacity of R.C columns wrapped with GFRP was reduced by fire to a high degree (approximately 53% reduction in the ultimate capcity).
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