Estudio geotécnico in Penagos

In Penagos, a substratum comprising sandstones, conglomerates and flysch predominates; collectively, these materials offer good conditions for shallow foundation, provided that their degree of compaction and alteration is verified. The occasional presence of limestones, dolomites and marbles introduces areas with higher mechanical strength, whereas the lesser contributions of fine sands, silts and, especially, gypsum, anhydrite and salts must be taken into account for their particular characteristics: gypsum and salts may present risks of dissolution and must be identified precisely in order to adjust the foundations accordingly. Overall permeability is low, although there may be localised accumulations of groundwater, which must be analysed at each specific site.

With regard to geotechnical hazards, Penagos exhibits notable seismicity, with 145 events over 30 years, albeit with a maximum magnitude (Mmax) of 4, which limits its influence on structural actions, but justifies its review in the design of the foundations. Given the occasional limestone and dolomite component, the presence of karst processes is significant and must be confirmed through direct investigation before defining the type of support, particularly in the presence of risks of cavities or sinkholes. The non-clayey substratum eliminates the problem of shrink–swell (expansivity), establishing karst and the possible dissolution of gypsum as the main factors to control in the geotechnical design.