Part of Special Issue "Precursory phenomena, seismic hazard evaluation and seismo-tectonic electromagnetic effects" Abstract. The spontaneous electrification of marble samples was studied while they were subjected to uniaxial stress. The Pressure Stimulated Current (PSC) technique was applied to measure the charge released from compressed Dionysos marble samples, while they were subjected to cyclic loading. The experimental results demonstrate that, in the linear elastic region of the sample, no PSC is recorded, while beyond the stress limit (s>0.60), observable variations appear, which increase considerably in the vicinity of sample failure, reaching a maximum value just before the failure. The emitted current is reduced on each loading cycle and it has a reciprocal dependence to the normalized Young modulus. The MCD model, applied out of the vicinity of sample failure explains successfully the above findings. The existence of a "memory-like" behavior of the sample, could justify the weakness or absence of electrical earthquake precursors, during an aftershock sequence.

No abstract

No abstract

No abstract

This paper focuses on the investigation of the three‐point bending tensile strength of Dionysos marble. Using the classical relationship obtained from the theory of elasticity, the effect of the span length, the thickness/width ratio and the orientation of the specimens in the indirect tensile strength were investigated. In total, 42 experiments were carried out, divided in three sets of specially designed beams. Finally, the calculated bending tensile strength is compared with the corresponding value obtained from Brazilian indirect tension as well as ring tests.