Chemo-mechanical modeling of artificially and naturally bonded soils

• Published in: Geomechanics for energy and the environment 2019-06, Vol.18, p.13-29
• Main Authors: Gajo, Alessandro, Cecinato, Francesco, Hueckel, Tomasz
• Format: Article
• Language: English
• Subjects: Bonded geomaterials; Chemo-mechanical coupling; Constitutive modeling; Destructuration; Dissolution; Micro–macro relationships
• ISSN: 2352-3808; 2352-3808
• DOI: 10.1016/j.gete.2018.11.005

Chemo-mechanical effects are known to be significant in a number of applications in modern geomechanics, ranging from slope stability assessment to soil improvement and CO2 sequestration. This work focuses on coupled chemo-mechanical modeling of bonded geomaterials undergoing either mechanical strengthening, due to increased cementation, or weakening, due to cement dissolution. A constitutive model is developed that accounts for the multi-scale nature of the chemo-mechanical problem, introducing some cross-scale functions establishing a relationship between the evolution of microscopic variables and the macroscopic material behavior, realistically following the evolution of the reactive surface area, cross-sectional area and the number of bonds along with dissolution/deposition. The model presented here builds up on a previously introduced framework. However, at variance with existing works, it is specialized on materials with only reactive bonds, such as carbonate cemented sandstone or microbially cemented silica sand. Model validation is provided upon reproducing different types of chemo-mechanical experimental datasets, on different naturally and artificially cemented materials, to establish the reliability of the proposed framework. •A chemo-mechanical model for bonded geomaterials is developed and tested.•The model is specialized for materials with only reactive bonds, and inert grains.•Unrealistic modeling situations are avoided thanks to key cross-scale functions.•The framework can be readily expanded to more complex constitutive assumptions.