Swelling can be defined as the volume increase experienced by any solid body when wetted. Many lithotypes (carbonate rocks, sandstones, igneous rocks) have expansive components in their composition; anhydrite and clay minerals are the two best-known expansive components in stone materials. Swelling strain can be easily quantified and swelling pressure determination is accessible in many geotechnical laboratories. This paper deals with the decay of stone due to swelling of clays and discusses the ways to take the swelling behaviour into account when the assessment of stone durability is concerned. It analyses the role of swelling in stone conservation and reviews some cases where this decay mechanism has a relevant role, explicit or implicitly.
Delgado, J. (2001). Evaluación del comportamiento expansivo de las rocas y su interés en conservación. Materiales De Construcción, 51(N°263-264), 183–195. https://doi.org/10.3989/mc.2001.v51.i263-264.363