The Static Plate Load Test aims to determine the load–deformation behavior of soil, from which it is possible to obtain the compressibility modules for the first and second loading cycles (Ev1 and Ev2), as well as the modulus of subgrade reaction or Coefficient of Subgrade (Ek), depending on the type of analysis and the specific technical requirements. This test is widely used, mainly in the field of road infrastructure, and is increasingly requested for the acceptance of wind turbine foundation platforms, as the results are highly reliable for characterizing the geotechnical behavior of soils.

The method consists of applying different load levels to the soil under study using a hydraulic jack, which transfers the force through a steel plate of either 300 mm or 600 mm in diameter. For each loading step, the settlements are measured with dial gauges placed at three points on the plate, preferably positioned 120° apart.

After the pre-loading phase, the system is unloaded in stages, while vertical displacements of the plate are again recorded. This procedure is performed at least twice, and for each cycle, a stress–strain curve can be fitted to the measurements, allowing the maximum stress of each cycle to be determined and the corresponding deformation modules to be calculated.

Currently, Geotecnia Patagonia has both 300 mm and 600 mm plates, as well as automated systems for recording loads and deformations, thereby eliminating human error associated with manual measurements and ensuring more accurate and reliable results.