Geotechnical study in Sant Antoni de Portmany

In the municipality of Sant Antoni de Portmany, hard materials predominate, such as limestones, dolomites and marbles, together with a significant proportion of compacted gravels and sands. These soils usually provide good bearing capacity, which favours the choice of shallow, direct foundations in many projects. However, the occasional presence of overconsolidated clays and marls and the low percentage of loose sands or expansive clays indicate that, although localised areas of lower competence may exist, the overall setting is conditioned by a solid, stable substrate.

Seismic activity in Sant Antoni de Portmany is moderate, with 24 recorded events over the last 30 years and a maximum magnitude of 3.2, suggesting low structural risk from ground movements. However, as this is an environment where carbonate materials predominate, it is essential to verify the existence of karst phenomena before defining the foundation solution, since the presence of cavities can seriously affect stability. In view of this situation, checking for karst is the main geotechnical constraint to consider in any geotechnical study of the area.