Geotechnical study in Chiva

In the municipality of Chiva, the ground is mainly dominated by formations of limestones, dolomites and marbles, to which occasional occurrences of fine sands with silts and evaporitic materials such as gypsum, anhydrite and salts are added. In general, these carbonate materials show good bearing capacity, although dissolution-related phenomena linked to the presence of gypsum, anhydrite and salts must be monitored; although they do not predominate, they can affect the foundation in specific sectors. In general terms, hard rocks allow for shallow or semi-deep foundations, although the localised presence of sands or silts requires the stratigraphy to be characterised in detail before foundation work and to avoid bearing on soft or low-competence levels.

Seismic activity in Chiva is considered moderate, with 31 recorded events over 30 years and a maximum magnitude of 2.8, values which do not entail a critical influence on ordinary structural design. The main risk is the possible existence of karst-related processes associated with limestones and dolomites; therefore, the geotechnical study must thoroughly verify the presence of voids or cavities before defining the foundation solution. In addition, the presence of gypsum requires special attention due to the potential for dissolution and subsidence, whereas the absence of an underlying clay substrate rules out risks of expansivity in the area. The main geotechnical constraint in Chiva is therefore the verification of instabilities associated with karstification and evaporitic materials.