Stress Memory in Acoustic Emission of Rock Salt Samples in Cyclic Loading under Variable Temperature Effects

Abstract

The behavior of acoustic emission in uniaxial cyclic loading of rock salt samples from the Kaliningrad deposit is determined. The samples were tested under varied temperatures and ratios of maximal stresses in sequential loading cycles. The experimental curves of acoustic emission activity and maximal stress and temperature of the previous cycle are obtained. Stress memory in acoustic emission manifests itself equally stably under constant higher and lower temperatures. Memory of the maximal stress of the previous cycle persists under higher temperature in the next cycle and vanishes under lower temperature in the next cycle. In case of the same maximal stresses and constant or higher temperatures in the successive cycles, the stress memory effect is vague: the stress estimated on this base is lower than the maximal stress of the previous cycle.