Effect of Microstructure and Relative Humidity on Strength and Creep of Gypsum

Abstract The wide range of gypsum facies observed all over the world and strong heterogeneity that may be present even within a single often cause an inhomogeneous mechanical response that, if neglected, particularly dangerous in framework underground excavations. In addition, is sensible to presence water. high relative humidity conditions registered quarries imply additional worsening properties. study, strength creep natural rock are investigated, considering influence material conditions. material, quantified with MIP SEM analyses, strongly affect response. To this intrinsic variability, external parameter as generate reduction increase strain rate long-term tests. effect these elements quarry discussed constitutive model experimental results provided.