Geotechnical study in Alcázar de San Juan

The predominant substrate in Alcázar de San Juan consists mainly of limestones, dolomites and marbles, with a significant presence of compact gravel and sands, as well as smaller proportions of gypsum, anhydrite and salts. These materials generally provide a good bearing capacity, which favours the execution of shallow foundations, particularly on the compact horizons of carbonate rock and gravels. However, the occasional distribution of gypsum and salts implies a potential risk of dissolution processes, and the existence of muds and peats, although rare, advises ruling out these levels as a foundation base due to their low geotechnical capacity and high compressibility.

Seismicity within the municipal term is moderate, with 44 recorded events over three decades and a low maximum magnitude (Mmax 3), so although present, the seismic risk does not represent a critical constraint in standard structural design. It is relevant to consider the possible existence of karstic cavities associated with the carbonate and gypsum-bearing rocks, which is why the necessary checks in this regard are essential before designing any type of foundation. The absence of clayey substrate rules out risks due to expansiveness. The main technical constraint in the municipality lies in potential karstification and the interaction with soluble materials, which must be analysed in detail in each geotechnical study.