Description
The increasing deployment of wind farms in tectonically active subduction regions poses new challenges for seismic hazard assessment. Traditional Probabilistic Seismic Hazard Analysis (PSHA) generally adopts a single-site approach and relies on conventional intensity measures (IMs) such as peak ground acceleration (PGA) or spectral acceleration at the fundamental period (Sa(T1)). However, these assumptions may not adequately represent wind farms, which can extend over more than 10 km² and comprise multiple spatially distributed turbines with long fundamental periods (3–5 s) and highly flexible dynamic behavior.In Chile—one of the world’s most active subduction regions currently experiencing rapid wind energy expansion—this issue becomes particularly relevant. Wind turbines differ markedly from conventional civil structures due to their slender geometry, high flexibility, and strong higher-mode participation. Existing hazard frameworks often rely on point-source representations, potentially leading to biased estimates of seismic demand across turbine arrays. To address this limitation, this study applies a PSHA framework that incorporates the spatial correlation of IMs to provide a more realistic representation of site-to-site variability across wind turbine locations in Chilean subduction zones.
The analysis focuses on the average spectral acceleration (Saavg(T1)), an IM widely recognized as an effective predictor of seismic demand for flexible, long-period systems such as wind turbines. Unlike single-period IMs, Saavg(T1) accounts for higher-mode effects and the broadband characteristics of ground motions. However, its behavior under subduction conditions—characterized by long-duration shaking and complex frequency content—remains insufficiently explored. Accordingly, several averaging windows are examined to assess the sensitivity of Saavg(T1) and identify representative period ranges for turbines. The results, obtained from multiple IMs and return periods, reveal measurable intra-site variability, highlighting the need for spatially consistent approaches in the seismic hazard characterization of distributed wind turbine systems.
This study constitutes the first phase of a broader research initiative aimed at advancing multi-hazard assessment for wind turbines in Chile, integrating seismic and wind hazards along with operational and fatigue effects. The findings enhance understanding of seismic hazard representation for wind turbines in subduction environments and provide a foundation for future engineering guidelines, design standards, and resilience-oriented energy policies.
| Period | Oct 2025 |
|---|---|
| Held at | GIASIS, Chile |
| Degree of Recognition | National |