Geotechnical study in Which

In the municipality of Quel, sandstones, conglomerates and flysch predominate; these materials are characterised by good strength and geotechnical stability. These soils, together with the gravels and compact sands present in smaller proportions, generally provide a favourable bearing capacity for the direct foundation of structures, provided that foundations are not supported on the localised levels of fine sands and silts, which are less competent materials. The presence of masses of water in isolated areas suggests the possible existence of shallow aquifers, although the overall permeability of the ground is low, limiting potential drainage or capillary rise problems.

The recorded seismic activity is high, with 200 events over the last 30 years and a maximum magnitude of 4, which requires a careful assessment of seismic actions in the structural design of new developments, in accordance with seismic-resistant regulations. Since the dominant formations are not clayey, a risk associated with expansive clays is ruled out, thereby simplifying the ground stability analysis. The main constraint to be addressed in geotechnical studies for Quel will therefore be control of seismicity and the correct identification of specific zones with lower bearing capacity.