Geotechnical study in Castilblanco de los Arroyos

In Castilblanco de los Arroyos, the predominant materials correspond to granite, gneiss and other igneous rocks, which cover close to half of the municipality. These lithologies are characterised by high strength and low deformability, providing a notable bearing capacity for shallow works and infrastructures. The shales and schists present in smaller proportions may introduce anisotropies or planes of weakness, although in general these soils are suitable for shallow foundations, with the recommendation to verify local weathering. Other lithotypes such as limestones, dolomites, marbles and sandstones have a residual presence, so their influence is limited in most projects.

With regard to geotechnical risks, the seismicity in the municipality is significant, with 63 events over 30 years, although the maximum magnitude recorded (Mmax = 2.9) is low and does not impose special structural requirements. The analysis of expansivity rules out relevant issues, since the subsoil is not clayey. In addition, there is no risk associated with karst processes in the area. Thus, the main geotechnical consideration in Castilblanco de los Arroyos stems from the hard, compact nature of the soils, which facilitates foundation works, although it will be necessary to locally assess the freshness and fracturing of the rocks to ensure the expected behaviour.