Chemical softening and hardening of geomaterials in situ
نویسنده
چکیده
Dependence of mechanical properties of geomaterials on the variable chemical environment or advancement of chemical or mineralogical reactions is known to be a crucial factor in many cases of mechanical stability of geo-masses. Processes of mineral dissolution usually results in material weakening while precipitation of minerals such as of silica in aging or calcite in clay fractures may lead to material strengthening. Experimental background of the process of aging of deep sediments is presented. It is postulated that aging consist of two processes of dissolution and precipitation affecting two different structural components. Their respective chemical softening and chemical hardening within plasticity theory is described. The joint response of the two components to further loading is then modeled.
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