Gypsum is widely distributed in Tunisia occurring in the formation of Triassic age. The gypsum deposit of Mellegue is the alabastine type with a little of the porphyroblast type and contains traces of clay minerals an...Gypsum is widely distributed in Tunisia occurring in the formation of Triassic age. The gypsum deposit of Mellegue is the alabastine type with a little of the porphyroblast type and contains traces of clay minerals and calcite. It is a moderately strong rock in terms of its unconfined compressive strength of 16 Mpa and tensile strength of 3.35 Mpa. Triaxial testing values indicated an apparent cohesion of 10 Mpa and an angle of friction of 26°. The gypsum studied had a percentage of SO<sub>3</sub> of 41.71% and a percentage of CaO of 32.9%. All the samples had low densities according to the International Association of Engineering Geology (IAEG) classification and exhibited a moderate porosity whether effective or absolute. The gypsum proved to be moderately strong when tested in unconfined compression and tensile strength. Thermal analysis indicated a total weight loss of 20.27% and the whiteness index about 90%. This proved a high degree of whiteness. The time of setting can be considered short and medium, which is quite favorable for industrial application compared with other gypsum deposits currently operated.展开更多
文摘Gypsum is widely distributed in Tunisia occurring in the formation of Triassic age. The gypsum deposit of Mellegue is the alabastine type with a little of the porphyroblast type and contains traces of clay minerals and calcite. It is a moderately strong rock in terms of its unconfined compressive strength of 16 Mpa and tensile strength of 3.35 Mpa. Triaxial testing values indicated an apparent cohesion of 10 Mpa and an angle of friction of 26°. The gypsum studied had a percentage of SO<sub>3</sub> of 41.71% and a percentage of CaO of 32.9%. All the samples had low densities according to the International Association of Engineering Geology (IAEG) classification and exhibited a moderate porosity whether effective or absolute. The gypsum proved to be moderately strong when tested in unconfined compression and tensile strength. Thermal analysis indicated a total weight loss of 20.27% and the whiteness index about 90%. This proved a high degree of whiteness. The time of setting can be considered short and medium, which is quite favorable for industrial application compared with other gypsum deposits currently operated.