Damage Assessment in Syracuse Limestone Specimens by Frequency Analysis of Elastic Emissions

This paper investigates the mechanical behaviour and the damage evolution on four different size scale Syracuse limestone specimens, under compressive loading through the frequency spectra analysis of elastic emissions (ELE). ELE are detected in a very low frequency range (from 20 kHz down to few hertz) and are characterized by high levels of released energy. In the damage process, approaching to the large fractures and the final collapse of the material, bursts of ELE are observed. Amplitude, cumulate number, rate in time and frequency peak distribution of ELE indicate the specimen degradation, from the integrity state to its irreversible plastic deformations. This study focuses on the estimation of the ELE amplitude and frequency distribution in order to achieve informations and analytical previsions about damage evolution both on the laboratory scale and in situ, such as Syracuse Athena Temple.