The Indication of Damage in Concrete by Amplitude-Frequency of Acoustic Emission Signal

When the concrete is in the process of load, the curve of amplitude - frequency shows significant characteristic of exponential. As the load increases, the acoustic emission signals gradually become complete, the more obvious features of this exponential function. Using the least squares method, we can get an empirical function expression by fitting the data.Function expression has different regression coefficients in different load stages, and regression coefficients changing with load also presents certain rules, which has a good indication to qualitative process of structural damage.