Geotechnical study in Arroyo de San Serván

At Arroyo de San Serván, compact gravel and sand soils predominate, occupying most of the municipality and providing a favourable base for direct foundations thanks to their high bearing capacity. The occasional presence of sandstones, conglomerates, flysch and limestones makes it possible to consider conventional foundation alternatives in most projects, whereas sporadic levels of fine sands and silts require specific characterisation to rule out the risk of localised subsidence. It is recommended to avoid foundation on bodies of water and organic materials.

Seismicity within the municipal district is very low, with only a single event in the last 30 years and a maximum magnitude of 1.6, so it does not represent a relevant conditioning factor for structural design. Since the substrate is non-clayey, the risk of expansivity is ruled out, and the absence of karst simplifies geotechnical viability studies. Thus, the main focus should be on characterising the grain size distribution and the compactness of the soils in order to optimise the foundation design.