Coupling transport of chemical species and damage of bonded geomaterials

The purpose of this paper is to describe a solution strategy to model the transport of a dilute solute into a porous material, the subsequent reactions, the evolution of material degradation and the mechanical response of the solid in terms of inelastic strains. The convection-diffusion reactive equation is split in a pure advection system of PDEs solved using a Taylor–Galerkin discretization technique and a system of ordinary differential equations solved with a fourth-order Runge–Kutta algorithm. The constants defining the rate of the chemical reaction, in this case, the dissolution of calcite under acid action, are determined with experimental tests. The constitutive model used to represent the debonding process has been developed by Nova and co-workers and implemented in the Finite Element computer code GeHoMadrid. The experimental response obtained in carbonatic soft rock specimens using a “weathering test device” is reproduced by means of the proposed strategy. Finally, a time dependent geotechnical application concerning the weathering induced subsidence of a shallow foundation is presented by comparing experimental results and numerical simulations.