Revisions to Reinforced Concrete Fatigue Design Standards: Affects on Wind Turbine Foundations
DNVGL-ST-C502, the standard for reinforced fatigue design in the wind energy industry for over a decade, for both onshore and offshore wind energy foundation design, has published a minor revision relevant to the development of onshore wind projects. This revision includes clarifications of existing provisions of the standard based on feedback from the design community, owner-operators, and contractors, in order to anticipate further development of foundations as the wind energy industry continues to grow.
Clarifications to areas such as fatigue damage limits, material testing requirements, and definitions for terms used in the analyses are incorporated into this most recent revision. While this is a minor revision and no changes have been made to the underlying provisions of the standard, the DNV GL Renewables Advisory team is happy to help discuss the standard with you and assist with any foundation design challenges. DNVGL-ST-C502 January 2020
The International Electrotechnical Commission is also scheduled to publish IEC 61400-6, “Tower and foundation design requirements” in March 2020. This standard utilizes DNV GL ST C502 with other international standards and national building codes, to provide a unified framework for application to wind energy structures. The 61400-6 standard is now being considered by national adoption committees for incorporation into practice guidance documents to be used in the US practice. DNV GL participated in the international development of the standard, and is actively participating in the adoption committee, in order to ensure that the adoption of the standard into US practice is consistent with design and construction practices common to utility scale wind energy projects in the US. The IEC 61400-6 international standard will be available from the IEC Webstore when published.
ACI 318-14 has been adopted by several jurisdictions around the US, and contains several changes and updates over the prior standard that can affect design of reinforced concrete foundations for wind turbines. ACI 318-14 is available at the concrete.org website.
DNV GL is happy to discuss any of the ongoing changes to the design standards and building codes, as we have a detailed familiarity with the standards that we work with every day. Please reach out to the DNV GL civil team or any of the independent engineering project managers.