Macro-Microscopic Deterioration Behavior of Gypsum Rock after Wetting and Its Constitutive Model Based on Acoustic Emission

Gypsum rock is highly sensitive to a water environment due its unique physical and chemical properties, such as high solubility. After wetting, the internal microstructure of gypsum damaged, mechanical properties deteriorate accordingly, leading serious engineering problems for gypsum-bearing geotechnical structures. Therefore, it particularly necessary investigate deterioration behavior after wetting. In this paper, rocks with different contents were studied. The relationship between content immersion time was established through test. scanning electron microscope (SEM) images showed that became looser more complex increased. fractal dimensions SEM calculated quantify degree damage These increased increasing time, but increase rate tended be slow. responses by triaxial compression tests, concomitant acoustic emission (AE) characteristics in loading processes had positive correlation AE frequency negative cumulative count. Based on characteristics, constitutive model function developed can reproduce