Geotechnical study in Orcera

In Orcera, the predominant soils are phyllites and schists, followed by relevant proportions of limestones, dolomites and marbles, as well as the occasional appearance of gypsum formations and soft expansive clays. In general, the bearing capacity will be conditioned by the phyllitic or schistose nature of the ground, which is of low permeability and offers good competence for conventional shallow or semi-deep foundations. The carbonated formations require a specific analysis of the rock mass, whereas the isolated presence of gypsum and salts introduces a certain vulnerability to ground dissolution and subsidence phenomena.

From the standpoint of hazard, there is moderate seismic activity (11 events in 30 years, with Mmax of 1.9), insufficient to significantly condition structural design. It is nevertheless essential to pay attention to the possible presence of karstification in carbonated media; for this reason, it is imperative to verify the existence or absence of cavities or voids before carrying out deep foundations. No significant risk of expansivity is detected, as the substrate is not clayey, with the main technical constraint focused on verifying karst and the possible development of processes related to the dissolution of gypsum.