In seismology, Gutenberg-Richter relationship log N=a−bM is an empirical relationship be- 10 tween the magnitude of earthquake and its recurrence frequency. The constant ‘b’, a damage parameter, in the expression is called the b-value and is the log linear slope…
In seismology, Gutenberg-Richter relationship log N=a−bM is an empirical relationship be- 10 tween the magnitude of earthquake and its recurrence frequency. The constant ‘b’, a damage parameter, in the expression is called the b-value and is the log linear slope of frequency-magnitude distribution. An analogy is drawn between fault rupture and failure process in concrete. Acoustic emission (AE) energy is released, in the form of waves having certain peak amplitudes, during the failure process of concrete. Peak amplitudes of the AE signals are being used while estimating the b-value during fracture. Right from the onset of cracks till fail- ure, the AE events are recorded with their peak amplitudes and corresponding absolute energies. Interestingly, the AE energy release has been observed to be in clusters. These clusters have been called by the authors as AE quanta. They are utilized as groups instead of using magnitudes of arbitrary group of events for obtaining the b-value. Unlike in seismology, wherein the b-value could be nearly unity, it is found more interestingly that the b-value from quanta is much less than that obtained from the amplitudes.