Geotechnical study in Roquetas de Mar

In Roquetas de Mar, fine sands, silts and compacted gravels predominate, accompanied by a significant proportion of limestones, dolomites and marbles. In general, these materials exhibit good bearing capacity, although the layers of fine sands and silts may show some compressibility in localised areas, thus recommending an appropriate investigation into stratigraphic uniformity. The occasional presence of gypsum, anhydrite and salts should be considered in view of its potential risk of dissolution, and the masses of groundwater suggest a medium permeability, which may require particular attention when selecting the foundation formation level to avoid problems with differential settlement or the presence of a high water table.

Seismicity in the municipality is moderate, with 24 events recorded over 30 years, and a maximum magnitude (Mmax) of 4, sufficient for seismic actions to be taken into account in the structural analysis. The subsoil is not clayey, so the risk of expansivity is ruled out. It is worth bearing in mind the possibility of karstification in the carbonate materials, meaning that verification of this is required before executing any foundation, as the presence of cavities or dissolution processes may compromise the stability of the structures. For all these reasons, ground characterisation and hydrogeological monitoring constitute the main constraints for the geotechnical study in Roquetas de Mar.