Project Period: April 2021 – January 2022
Client:
Consorcio Eólico
Location:
Comuna de Laja,
Región del Bío Bío
Project Overview
Pangea Geotechnia carried out a comprehensive geotechnical site investigation to support the conceptual engineering of the **Rinconada Wind Farm**, located in the **Biobío Region, Chile**. The investigation included **ten Standard Penetration Test (SPT) boreholes** drilled to depths of up to **25 meters**, together with **high-resolution pressuremeter testing**, trial pits, triaxial testing, direct shear testing, permeability testing, and geophysical surveys to characterize the subsurface conditions. The geotechnical assessment covered several geological units—including the **Coastal Batholith**, unconsolidated deposits, the **Eastern Series**, and the **La Montaña Formation**—and identified varying foundation conditions for the wind turbines, electrical substation, transmission line, and other project infrastructure. The investigation identified a high liquefaction potential in areas with loose to medium-dense sedimentary soils and a shallow groundwater table. As a mitigation measure, **gravel columns** were recommended to improve ground performance. In areas underlain by competent rock or dense soils, direct foundations on natural ground were found to be feasible, subject to local adjustments based on the degree of weathering. The study provided detailed recommendations for foundation design according to the prevailing ground conditions, including strength parameters derived from pressuremeter and triaxial testing, as well as seismic design considerations in accordance with the Chilean standard **NCh 2369**. This detailed subsurface characterization provided a sound technical basis for a safe and optimized structural design of the wind farm infrastructure.