Investigation of Fire Damage in Concrete by Post-peak Control Technique Associated with Acoustic Emission
This paper presents a new test method to investigate the influence of fire damage on stiffness, strength, toughness in macro-view and localization of micro-crack in micro-view of concrete by conducting uniaxial compressive test associated with acoustic emission (AE) after specimen subjected to heating with different thermos-conditions such as the rate of heating, maximum temperature, exposure time, as well as cooling condition. During the testing, the extensometer was used as feedback signal control to stabilize crack growth; the complete loading curve including pre- and post-peak stage was then obtained. Therefore, the evolution of AE microseismic sources with respect to loading process was also examined. The test results in macro-view show that the stiffness, strength, and toughness decrease with an increase in maximum temperature; the post-peak behavior from snapback (Class II) converts to snap through (Class I) at maximum temperature ranged 200–400 °C, whereas, in micro-view, the AE localization occurred earlier as the maximum temperature increased. When the maximum temperature reached 600 °C, the AE localization cannot be found during the uniaxial compressive test.
KeywordsFire damage Concrete Uniaxial compressive test Acoustic emission
Exposure time (min)
Heating rate (°C/min)
Load level (%)
Load level of AE localization (%)
Maximum temperature (°C)
The authors acknowledge the funding supplied by the Architecture and Building Research Institute, Ministry of the Interior, ROC (Taiwan).
- 1.Tovey, A. K. (1986). Assessment and repair of fire-damaged concrete structures-an update. ACI Special Publication, 92, 47.Google Scholar
- 2.Luo, B. Y. (2008). Fire-resistance property of reinforced lightweight aggregate concrete wall. Master Thesis, National Chung Hsing University, Taiwan.Google Scholar
- 3.ASTM. (1999). Standard definitions of terms relating to acoustic emission. American Society for Testing and Materials.Google Scholar
- 4.Kaiser, J. (1953). Undersuchungen Uber Das Aufrterten Geraucchen Beim Zevgersuch. Ph.D Thesis, Technische Hochschule, Munich.Google Scholar
- 9.Chen, L. H. (2001). Failure of rock under normal wedge indentation. Dissertation, University of Minnesota.Google Scholar