Geotechnical study in Abrera

In Abrera, sandstone, conglomerate and flysch substrates predominate; they account for most of the subsoil and generally offer a favourable bearing capacity for shallow foundations. Fine sands and silts are also present to a significant extent, and may require attention with regard to compaction and drainage. The occasional presence of overconsolidated clays and marls provides adequate strength, while the compact gravels and sands present in a smaller proportion may contribute positively to geotechnical performance, although their continuity at the specific site must be verified.

Seismicity in Abrera is very low, with only around five events over thirty years and a low maximum magnitude, which minimises this factor in structural design. No karstification phenomena are reported and although subordinate expansive clays are identified, their limited location and the climatic conditions notably reduce the risk of expansivity. The main aspect to control is lithological heterogeneity, and precise characterisation is always recommended in order to optimise the choice of foundation system.