Abstract
The detection of material damage is most important issue for maintenance and management of in-service concrete structures. In recent years, concrete damage is quantitatively evaluated by relation between newly development parameters and mechanical properties. By the author, damage evaluation parameters for concrete is developed by using acoustic emission (AE) method based on stress field. The AE is one of the useful methods for detection of elastic waves in stress field. In this study, damage evaluation of in-service concrete road wall is conducted by AE energy parameters analysis in core test. Testing structure is appeared to accumulation of cracking damage. The detected AE is compared to mechanical properties. Thus, the detected AE waves are closely associated with damage accumulation. This phenomenon is indexed by the detection of high energy AE at the initial loading stage, which is closely related to the strain energy calculated from the stress-strain curve. Therefore, the degrees of damage in concrete samples are quantitatively evaluated by AE energy parameter, even when the initial mechanical properties of concrete structure at the time of construction are unknown.
