Chemo-Mechanical Coupling in Bonded Geomaterials: Representations in Two Scales

Chemo-mechanical couplings in geomaterials have received increasing attention in recent years for a number of applications, ranging from the stability of slopes and coastal structures to geological CO2 sequestration. Chemical processes may result in strengthening or weakening effects, the latter being particularly critical for safety assessment in civil and energy engineering applications. In this work, coupling of chemical and mechanical processes in cemented soils and rocks is investigated by means of a micro-structure inspired model, consisting of an assembly of grains and bonds undergoing dissolution or deposition of mineral mass, affecting geometrical characteristics of the system and thus determining the evolution of specific surface area and of bond cross-sectional area at the micro-scale, and of porosity at the macro-scale, which become key variables linking the micro-scale and macro-scale mechanisms. The resulting micro- to macro-scale model is validated against the available experimental evidence, consisting of a number of different chemo-mechanical experiments on calcarenite. The model is thus shown to provide a flexible framework for consistent interpretation of experimental loading paths, and can be readily extended to more complex materials or to incorporate additional effects.

Duke Scholars

Author Tomasz Hueckel Civil and Environmental Engineering