EVALUATION OF PLASTIC DAMAGE IN CONCRETE BY ACOUSTIC-EMISSION

This paper presents an experimental observation of the relation between the plastic damage and the acoustic emission (AE) events in concrete subjected to uniaxial compressive loading. To examine the effect of the degree of the initial deterioration on the plastic damage, both undamaged and damaged concrete specimens were tested. In the damaged specimens, the damage was induced using different numbers of freezing-thawing cycles to achieve different initial deterioration before loading. It is found that as the plastic damage increases the activity of AE signals increases. Moreover, it is noticed that the degree of the nonlinearity of plastic damage-AE event relationship depends significantly on the initial deterioration. The current investigation may provide a new procedure for core testing to evaluate concrete deterioration because the conventional strength and Young's modulus are less sensitive to the damage.