Estudio geotécnico in Isona i Conca Dellà

In Isona i Conca Dellà, sandstones, conglomerates and flysch predominate as the substrate, accounting for the majority of the ground present and providing good bearing capacity for shallow foundations, except in the case of discontinuities or localised alterations. Limestone, dolomites and marbles are also found in smaller proportions, as well as some white expansive clays and hard clays/marl, although the latter are considered occasional and can normally be managed in the foundation design approach. The overall low permeability of the materials limits infiltration, which may benefit conventional substructures; however, it is necessary to take into account local aquifers in new-build projects.

In terms of natural hazards, Isona i Conca Dellà has a very low level of seismicity, with only a single recorded event over 30 years and a maximum magnitude of 1.5, meaning that seismic action does not pose any relevant constraint for structural design. However, the presence of carbonate formations requires considering the possible occurrence of karstic phenomena: it is essential to verify the absence of voids or instability before any foundation project, as this could compromise structural safety. The non-clayey substrate rules out the problem of expansivity in most cases, with karst being the main factor of concern in local geotechnical studies.