Geotechnical study in Blanca

In the municipality of Blanca, the geological substratum is composed mainly of limestones, dolomites and marbles, together with significant proportions of sandstones, conglomerates and flysch. These materials, generally compact and competent in nature, offer a good bearing capacity for shallow foundations. However, the occasional presence of overconsolidated clays and marls, although in the minority, requires their correct identification in geotechnical studies to ensure the stability of structures and to avoid problems associated with differential settlement. Fine sands and silts, for their part, could present a lower bearing capacity and should be assessed particularly in localised areas.

Seismicity in Blanca is moderate, with 26 recorded events in the last 30 years and a maximum magnitude of 3.1, which implies limited seismic risks although worthy of review depending on the structural scope of the project. It is important to highlight that the karst environment associated with the limestones and dolomites requires precise verification of the development of cavities before any foundation work, as the presence of voids or dissolution can significantly compromise the safety and stability of constructions. The non-clayey substratum rules out the risk of expansivity, so the main focus should be on the assessment and mapping of the karstification and the continuity of the bedrock substratum.