Title:
Pullout Behavior and AE Analysis of Large-Size Rebars (D43 and D57) from Concrete (Prepublished)
Author(s):
Yu-Cheng Kan, Kuang-Chih Pei, and Jyun-Ruei Wu
Publication:
Structural Journal
Volume:
Issue:
Appears on pages(s):
Keywords:
acoustic emission (AE); bond; concrete; large reinforcing bar; pullout test
DOI:
10.14359/51749301
Date:
11/6/2025
Abstract:
This study investigates the bonding behavior of large-diameter steel bars (D43 and D57) embedded in concrete using pull-out tests coupled with acoustic emission (AE) monitoring. These large bars, commonly used in nuclear containment structures from the 1970s, were compared with conventional steel bars (D19 and D32) across three concrete strength levels. All tests were performed under displacement-controlled loading using an MTS testing machine. Results indicate that ACI 408R provisions remain valid for large-diameter reinforcing bars. The test results showed that when specimens reached ultimate bond stress, the D57 bar developed only 12 to 16% of its yield strength, whereas the D19 bar reached at least 70%. AE monitoring effectively captured the debonding process, and cumulative AE hit counts correlated with the strain energy released at each loading stage, offering insight into bond failure mechanisms.