Location

London

Event Website

http://www.csce2016.ca/

Description

In this paper, acoustic emission (AE) monitoring was used to evaluate the bond behaviour of corroded reinforcement in reinforced concrete prism samples. The embedded reinforcing steel bars were pre-corroded to successive levels of corrosion up to 5% mass loss of steel by impressed current accelerated corrosion process. A total of 24 samples with variable bar embedded length (50 and 200 mm) and corrosion exposure (0%, 1%, 2%, 3%, 4%, and 5% of steel mass loss) were tested under pull-out tests. Two attached AE sensors were mounted at the surface of each specimen to continuously record the emitted AE signals throughout the pull-out tests. Several AE signal parameters (cumulative number of hits, signal strength, amplitude, and duration) were analyzed to characterize the extent of bond deterioration. These AE parameters were compared with the corresponding values of bond stress and free end slip until failure. Furthermore, an intensity analysis on AE signal strength was implemented for the condition assessment of bond integrity, which yielded two additional AE parameters: historic index (H (t)) and severity (Sr). The analysis of cumulative signal strength, H (t), and Sr results permitted the identification of two stages of bond degradation (micro- and macro-cracking) before bond splitting failure. Besides, intensity classification charts were developed using H (t) and Sr to quantify the bond damage (micro- and macro-cracking and bar slip) of existing concrete structures.


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Jun 1st, 12:00 AM Jun 4th, 12:00 AM

STR-845: CONDITION ASSESSMENT OF CORRODED REINFORCEMENT BOND TO CONCRETE BY ACOUSTIC EMISSION MONITORING

London

In this paper, acoustic emission (AE) monitoring was used to evaluate the bond behaviour of corroded reinforcement in reinforced concrete prism samples. The embedded reinforcing steel bars were pre-corroded to successive levels of corrosion up to 5% mass loss of steel by impressed current accelerated corrosion process. A total of 24 samples with variable bar embedded length (50 and 200 mm) and corrosion exposure (0%, 1%, 2%, 3%, 4%, and 5% of steel mass loss) were tested under pull-out tests. Two attached AE sensors were mounted at the surface of each specimen to continuously record the emitted AE signals throughout the pull-out tests. Several AE signal parameters (cumulative number of hits, signal strength, amplitude, and duration) were analyzed to characterize the extent of bond deterioration. These AE parameters were compared with the corresponding values of bond stress and free end slip until failure. Furthermore, an intensity analysis on AE signal strength was implemented for the condition assessment of bond integrity, which yielded two additional AE parameters: historic index (H (t)) and severity (Sr). The analysis of cumulative signal strength, H (t), and Sr results permitted the identification of two stages of bond degradation (micro- and macro-cracking) before bond splitting failure. Besides, intensity classification charts were developed using H (t) and Sr to quantify the bond damage (micro- and macro-cracking and bar slip) of existing concrete structures.

http://ir.lib.uwo.ca/csce2016/London/Structural/29