Retrofitting Reinforced Concrete One–Way Damaged Slabs Exposed to High Temperature

Exposure of reinforced concrete buildings to an accidental fire may result in cracking and loss the bearing capacity their major components, columns, beams, slabs. It is a challenge for structural engineers develop efficient retrofitting techniques that enable RC slabs restore integrity, after being exposed intense fires long period time. Experimentalinvestigation was carried out on twenty one slab specimens made self compacting concrete, eighteen them are retrofitted with CFRP sheets burning loading till failure while three (which represent control specimens) sheet without burning. All had been tested simply supported span subjected two-point loading. The main variables were effect different temperature levels (300ºC, 500ºC 700ºC),different compressive strength (20MPa, 30MPa 40MPa) cooling rate (gradually sudden conditions) behavior way .The response each specimen investigated terms load-deflection behavior, ultimate load carryingcapacity mode failure. experimental results, generally, indicate using restored flexural values nearly equal or lower than those reference slabs, exhibited larger deflection at loads. Retrofitted regained about 93.95% 97.92% original capacity(before retrofitting) other from 42.% 84% specimens. Most failed by crushing mid partial debonding certain systems also observed few cases