Paper Title
Concrete Repair Materials Under Severe Fire Or Freeze-Thaw Condition

Abstract
Some concrete structures exposed to severe environmental conditions which might require maintenance or strengthening. In this study, Reactive Powder Concrete （RPC）was used to investigate the effect of strengthening concrete members by fire-damage test or freeze-thaw test. The results show that the mechanical properties of RPC possess high strength, toughness, and freeze-thaw resistance. The CFRP (carbon fiber reinforced plates) wrapping specimens exposed at 300 ℃ showed totally failure with the deterioration of the adhesive. The RPC with bonding 10 mm thickness specimens exposed at 400 ℃ still in good shape. The RPC with 1-cm or 2-cm thickness on strengthening concrete members could be obtained specific retrofit effects. The performance of RPC specimens is better than those of CFRP wrapping specimens during high temperature exposure. Index Terms- RPC, CFRP, freeze-thaw, Strengthening