Geotechnical study in Trebujena

In Trebujena, soils formed by fine sands and silts predominate. They cover most of the municipality and are usually associated with an intermediate-low bearing capacity, which calls for special attention in selecting the type of foundation. The occasional presence of limestones, dolomites and marbles introduces specific areas of more competent substrate, although these ground conditions are in the minority. On the other hand, the limited extent of sandstones and conglomerates and the existence of water bodies must be assessed in detail to ensure that foundations are not placed in the less stable areas or in areas with a higher risk of saturation.

Seismic activity in Trebujena is very low, with only one recorded event in 30 years and a low maximum magnitude of Mmax 2, so it does not constitute a relevant constraint. As regards expansivity, expansive clays appear in a subordinate manner and, in addition, the surrounding area does not show a significant water deficit, mitigating the risks associated with swelling. Therefore, the main geotechnical constraint in Trebujena continues to be the variability in the bearing capacity of the fine sediments, which requires accurate characterisation of local hazards to the stability and settlement of foundations.