Geotechnical study in Numancia de la Sagra

In Numancia de la Sagra, the geological subsoil is dominated by limestones, dolomites and marbles, with sandstone, conglomerates and flysch appearing frequently, which generally gives the ground good bearing capacity for foundations. More sporadically, gravels, compacted sands and small areas containing gypsum, anhydrite and salts can be found; these materials may present problems associated with dissolution. The dominant soils favour shallow foundation solutions, although in the presence of soluble materials, a more detailed analysis will be needed to determine long-term stability. In addition, the existence of aquifers, albeit moderate, may influence the hydromechanical behaviour of the ground and the choice of the most suitable foundation type.

Seismicity within the municipality is very low, with a single event and a maximum magnitude of 2.1 over the last 30 years, so it does not constitute a relevant constraint in structural design. However, the presence of karst makes it mandatory to carry out a thorough assessment of the ground before executing any foundations, as cavities or associated dissolutions may exist, especially in areas with gypsum and salts. Likewise, the identification of locally predominant expansive clays represents a clear risk to stability and must be given special attention during the geotechnical study. In conclusion, the main precaution in Numancia de la Sagra is the specific verification of both karst risk and the expansive potential of the clays present in certain sectors.