  The observations show that the collapse of underground limestone mines
results from a progressive failure due to gradual weathering of the rockmass.
The following stages can be considered for the limestone weathering and
degradation process in underground mines: condensation of the water on the roof
of the gallery, infiltration of water in the porous rock, migration of the air
CO2 molecules in the rock pore water by convection and molecular diffusion,
dissolution of limestone by CO2 rich water and consequently, reduction of the
strength properties of rock. Considering this process, a set of equations
governing different hydrochemo-mechanical aspects of the weathering phenomenon
and progressive failure occurring in these mines is presented. Then the
feasibility of numerical modelling of this process is studied and a simple
example of application is presented.
