The objective of this study was to evaluate the in-situ serviceability of cellulose fiber reinforced concrete (CFRC) pipes using Acoustic Emission (AE). Three-edge-bearing test was conducted on CFRC pipes in the laboratory in accordance with ASTM C497-05. Pipes were saturated in water for various periods of time to simulate the practical field situations of CFRC pipes with different service life exposed to moisture effects. AE sensors and LVDT were installed on pipes detect the damage phases during loading. Both monotonic and cyclic loading modes were conducted on the CFRC pipes. Results showed that the CFRC pipes generally exhibited the nonlinear load-displacement behavior before failure, yet the level of ductility was reduced with longer exposure to moisture condition. AE data were evaluated through two feature signals, that is, intensity analysis and calm ratio analysis. Results showed that AE can detect the onset of damage and the ultimate failure of CFRC pipes. Additionally, the analysis on CFRC pipes subjected to various moisture effects showed different features of AE results. It is found that intensity analysis can distinguish different periods of exposure to moisture and levels of ductility, which make it feasible to monitor the health of CFRC pipes under moisture effects.
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