Geotechnical study in Alhendín

In Alhendín, the predominant soils are composed of limestones, dolomites and marbles, accompanied by a significant proportion of gypsum, anhydrite and salts. The presence of carbonate materials gives the subsoil a notable bearing capacity, making it favourable for shallow foundations, provided that the degree of fracturing is not excessive. However, the presence of gypsum and salts introduces a potential risk of dissolution, so it is essential to identify any potentially unstable areas. Fine sands, silts and hard clays occur in smaller proportions and usually show good compactness, although layers of muds or peats are hardly detected and should be avoided as support for foundations.

Seismic activity in the municipality is notable, with 126 recorded events over the last 30 years and a maximum magnitude of 3.9, which must be taken into account in any detailed geotechnical assessment for buildings. As this is a carbonate area, there is the possibility of karst phenomena, so verification of voids, conduits or subsidence is a priority before founding. The absence of an clayey bedrock rules out risks of significant expansivity. The main constraint for the geotechnical study in Alhendín lies in characterising the possible karst and assessing the solubility of the salts and gypsum present in the soil.