Geotechnical study in Leioa

In Leioa, limestone, dolomite and marble strata predominate, which form the most usual base for foundations in the area. In general, these materials exhibit good mechanical properties, providing a high bearing capacity and favourable conditions for the execution of shallow direct foundations, except in localised areas where fine sands, silts or anthropogenic fill are present. It is essential to identify bodies of water and less competent materials, such as urban fill, in order to avoid differential settlement or stability problems.

Seismic activity in the municipality is notable, with 94 events over the last three decades and a moderate maximum magnitude (Mmax 3.7), which requires an appropriate assessment but without reaching the most severe constraints. No risks of karstification or expansive soils have been detected, since the substrate is not clayey, which eliminates concern about expansivity. The main geotechnical constraint in Leioa lies in the local heterogeneity of materials and the precise identification of unsuitable layers, which must be taken into account in the geotechnical study to ensure structural safety.