Geotechnical study in Les Franqueses del Vallès

In Les Franqueses del Vallès, the geotechnical study reveals a domain of substrates made up mainly of sandstones, conglomerates and flysch, with an occasional presence of fine sands and silts. These materials usually provide good bearing capacities, allowing the use of traditional shallow foundations, although attention will be needed to address the heterogeneity typical of conglomerate and flysch deposits. The existence of very extensive and high-permeability aquifers may require specific checks regarding hydrogeology and possible effects on long-term stability during excavations.

Seismicity in the municipality is very low, with only five recorded events over thirty years and a low maximum magnitude of 1.6, so its influence on structural design is practically negligible. No problems associated with karst processes are identified and, although there are expansive clays, their location is secondary or they occur in areas of low climate-related risk, which minimises their impact. Under local conditions, bearing capacity and the management of the groundwater table are positioned as the main geotechnical factors to assess.