Geotechnical study in Utrillas

In Utrillas, the strata are predominantly composed of sandstones, conglomerates and flysch, which account for almost half of the surface area, followed very closely by limestones, dolomites and marbles. These materials generally offer good conditions for foundations thanks to their high bearing capacity, although the occasional presence of gypsum, anhydrite and salts implies that attention must be paid to the risk of dissolution, especially in areas where these minerals outcrop. In addition, muds and peats, although infrequent, should be avoided as a supporting layer due to their low geotechnical competence.

Seismic activity in Utrillas is high, with more than 200 recorded events over 30 years and an estimated maximum magnitude of 4.7. Therefore, local seismicity is an essential parameter that must be considered in the calculation and structural design of any project. On the other hand, since it is a non-clayey substrate, the risk of expansivity is ruled out. However, the possible presence of karstification in limestones and dolomites must be checked rigorously before founding, as it may condition the ground stability.