Title Quantitative Damage Estimation of Reinforced Concrete Beams on Strengthen with CFRP Sheet based on AE Characteristic
Authors Lee Young-Oh ; Yun Hyun-Do ; Seo Soo-Yeon
Page pp.27-34
ISSN 12269107
Keywords Carbon Fiber Reinforced Plastic ; Reinforced Concrete beam ; Acoustic Emission ; b-value ; Damage Estimation
Abstract CFRP(Carbon Fiber Reinforced Polymer) has been widely used for reinforcement and rehabilitation of damaged concrete structure, and that offer many advantages when compared to conventional steel. Reinforced concrete structure reinforced with CFRP is difficult to estimate for damage, but characterization of acoustic emission (AE) can be demonstrated the micro damage that was not discovered from visual observation and it become known to an advantage that was discriminated from the existing nondestructive technique method. This study was investigated the evolution of fracture damage of reinforced concrete (RC) beams strengthened in flexure with CFRP sheets using AE technique, and developed an AE monitoring strategy that can determine the structural integrity of RC beams strengthened by external bonding of CFRP sheets. In order to analysis the acoustic emission signal of concrete beams reinforced with CFRP, a total of 4 specimens were tested under four point bending. CFRP is reinforced a bottom, side 40% and side 100% of specimen. And AE sensor is attached a side of specimen by triangle method. The aim of this study was to examine the emission of acoustic signals from four CFRP reinforced concrete beams at cracking, failure processes and the failure mechanism of specimens. The AE signal of the RC beams strengthened with CFRP was evaluated using the AE parameters, such as AE counts, amplitude, hits, duration time, amplitude/rise time and b-value. The two-dimensional AE source location was successful in measuring crack initiation and propagation in the RC beams strengthened with CFRP.