Dominant Frequency Characteristics of Acoustic Emissions in White Marble During Direct Tensile Tests

Excerpt

Acoustic emission (AE) is defined as elastic waves associated with a rapid release of localized stress energy that is propagated within a material. It has been proven to be a useful tool for studying rock fractures (e.g., Lavrov 2003; Prikry et al. 2003; Tham et al. 2005; Amann et al. 2011; Shukla et al. 2013; Liu et al. 2015; Moradian et al. 2016; Zhang et al. 2016). Parametric and waveform data are two basic forms of recordable AE data. In the past few decades, parameter analysis has been widely used to observe progressive damage processes resulting from AE, as well as to evaluate the degree of damage (e.g., Butt 1999; Baddari et al. 2011; Xie et al. 2011; Zhao et al. 2013; Zhang et al. 2015). However, a single complicated AE waveform still might conceal important information, or may even present misleading information, since it is discriminated by only a few parameters (Behnia et al. 2014). Thus, it may be difficult to adequately discriminate the characteristics of AE waveforms using such parameter-based approaches. …