• vaishnavi patil
• L.G. Kalurkar

This project presents the structural modeling, analysis, and design of a gravity-based foundation (GBF) for a 3.6 MW offshore wind turbine located approximately 12–15 km off the Alibaug coast in Maharashtra, India. The site features moderate water depths (15–25 m), a stratified soil profile comprising soft silty clay overlying dense sand, and lies within Seismic Zone III as per IS 1893. A finite element model of the foundation was developed in SAP2000 v26.2.0 using shell elements on a rigid base, incorporating soil–structure interaction with a pinned supports. The structure was subjected to combined static and dynamic environmental loads including wind, wave, buoyancy, seismic, and hydrodynamic forces, with load combinations defined in accordance with IS 875, IS 2911, IS 1893, IEC 61400-3, and API RP 2A-WSD. The analysis verified stress distribution, deformation limits, and dynamic response under critical conditions, ensuring compliance with safety and serviceability criteria. Modal analysis confirmed that natural frequencies are well-separated from turbine operational ranges, and API-based integration of SAP2000 enabled real-time simulation capabilities aligned with digital twin concepts for predictive maintenance and lifecycle monitoring.

Offshore wind turbine, gravity-based foundation, SAP2000, structural analysis, Alibaug Offshore Site, digital twin, environmental loads, code compliance, renewable energy, soil-structure interaction

"Analysis And Design Of A Gravity-Based Offshore Wind Turbine Foundation", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.12, Issue 8, page no.f605-f610, August-2025, Available :http://www.jetir.org/papers/JETIR2508584.pdf

"Analysis And Design Of A Gravity-Based Offshore Wind Turbine Foundation", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.12, Issue 8, page no. ppf605-f610, August-2025, Available at : http://www.jetir.org/papers/JETIR2508584.pdf