ABS: New Guide for Building Offshore Wind Installations

The classification society ABS released a new Guide for Building and Classing Offshore Wind Turbine Installations. This is the first Guide to specifically address design considerations for the bottom founded support structure of an offshore wind turbine situated in tropical storm prone areas on the US Outer Continental Shelf (OCS) such as the Gulf of Mexico and the East Coast. In addition to considering the well-established International Electrotechnical Commission (IEC) 61400 series of standards for wind turbines, the Guide also takes into account the American Petroleum Institute’s Recommended Practice for Planning, Designing and Constructing Fixed Offshore Platforms (API RP 2A), ABS’ offshore Rules and Guides and the unique environmental conditions on the OCS. Additionally, the Guide also specifies a unique set of strength design criteria for the steel support structure of an offshore wind turbine based on the commonly accepted working stress design (WSD) approach.

Normal stresses, as well as earthquake and other rare conditions are also defined. The Guide includes requirements for the survey during construction and installation and the survey after construction taking into consideration the uniqueness, such as serial fabrication and installation, of offshore wind turbines. ABS will offer turbine support structures that comply with the requirements and conditions of the Guide the A1 Offshore Wind Turbine Installation class notation. This notation will be listed in the ABS Record. The newly released ABS Guide for Building and Classing Offshore Wind Turbine Installations is available at the ABS website: Resources, Rules & Guides, Downloads, Publication #176. (Frank Maisano)