Nondestructive Evaluation of Concrete Structures by Advanced Acoustic Emission Techniques
By Masayasu Ohtsu
Concrete Journal, Vol.35, No.12, Dec. 1997
- Synopsis
- Research on acoustic emission (AE) has been conducted actively and extensively in concrete engineering. Originally, it was started as one of nondestructive testings for concrete. Then, the techniques for the measurement are properly developed and under standardization. AE techniques are practically applied to the inspection of concrete structures for maintenance. A new application is attempted to be developed. In a similar manner to the process control of manufacturing, AE measurements are applied to the construction process of concrete structures. These examples on the inspection and the process control are reviewed and discussed. Because AE waves are elastic waves due to microfracturing, identification of fracture mechanisms in concrete has been studied via AE technique. An advanced waveform analysis based on the moment tensor representation is developed. The procedure is successfully applied to fracture mechanics of concrete, clarifying the fracture process zone of concrete. Thus, the applications of advanced AE techniques to concrete engineering are updatedly summarized.
- Keywords:
- Acoustic Emission, Nondestructive Evaluation of Concrete, Moment Tensor Analysis, Maintenance, Process Control, Fracture Mechanics
