A study for the Multidisciplinary Center for Earthquake Engineering Research (MCEER) provides fragility functions for 52 varieties of mechanical, electrical, and plumbing (MEP) equipment commonly found in commercial and industrial buildings. For the majority of equipment categories, the MCEER study provides multiple fragility functions, reflecting important effects of bracing, anchorage, interaction, etc. The fragility functions express the probability that the component would be rendered inoperative as a function of floor acceleration. That work did not include the evidence underlying the fragility functions. As part of the ATC-58 effort to bring second-generation performance-based earthquake engineering to professional practice, we have compiled the original MCEER specimen-level performance data into a publicly accessible database and validate many of the original fragility functions. In some cases, new fragility functions derived by ATC-58 methods show somewhat closer agreement with the raw data. Average-condition fragility functions are developed here; we will address in subsequent work the effect of potentially important—arguably crucial—performance-modifying factors such as poor anchorage and interaction.

With the expected introduction of wind turbine facilities for the generation of electricity to the US Outer Continental Shelf (OCS) waters, there is a need to evaluate how the long term operations of these facilities can be ensured through Integrity Management (IM) activities, particularly inspections. There is a long operational history of IM in the Gulf of Mexico, offshore California and Alaska, and around the world for fixed and floating oil and gas platforms. Both prescriptive and Risk- Based Inspection (RBI) methodologies have been established and implemented. This experience provides a foundation for implementing similar integrity management programs for offshore wind turbine facilities. This paper describes a guidance document developed to assist operators and regulators in developing IM programs for offshore wind farms, the incorporation of existing guidance for subsea structures, above-water structures and access systems, along with guidance from subject matter experts regarding critical inspection areas, inspection techniques, and inspection intervals that are unique to wind turbine facilities. This work was funded by the US Department of the Interior, Minerals Management Service (MMS). Development Approach An integrity management program is designed to ensure the safe and efficient operations of a facility over its service life. It is comprised of three primary activities:Inspection activitiesContinuous monitoring activitiesEngineering evaluation and data management This basic framework has been used extensively with offshore oil and gas platforms worldwide. Coupling this with inspection and monitoring practices unique to wind turbine facilities (both onshore and offshore) provides a basis for developing guidelines for an offshore wind turbine integrity management program. These guidelines and the approach used in their development are documented in MMS TA&R Project 627, " Inspection Methodologies for Offshore Wind Turbine Facilities?? [1]. Information from regulatory standards, industry recommended practices, and subject matter experts was used to divide a typical offshore wind turbine facility into specific systems and structures with similar inspection scope, frequency and approach. The highlighted critical inspection locations were coupled with practical inspection realities (e.g., what can be accessed and how can areas be inspected) important to developing a successful integrity management program. This paper provides an overview of the MMS TA&R Project 627 [1] including:Description of a typical offshore wind turbine facilityPotential failure modes and inspection techniquesRecommended integrity management guidelines

The American Wind Energy Association (AWEA), as a standards development organization, sponsored the development of recommended practices (RP) for offshore wind turbine facilities and published its RP report in 2012. The challenges faced by the emerging offshore wind energy industry parallel many of the challenges that were faced by the offshore oil and gas industry in its infancy. These challenges are documented and addressed in the development of the AWEA RP and are described in this paper. The paper discusses how the more mature American Petroleum Institute oil and gas standards were interfaced with International Electrotechnical Commission and other wind turbine and offshore industry standards to provide guidance for reliable engineering design practices of these mechanically dynamic, fatigue-driven offshore wind energy systems. Uncertainties requiring further validation and analysis are also described.

As the offshore wind industry matures and projects begin to expand to deeper water regions, various floating systems are being considered to support wind turbines. This paper explores the feasibility of a Tension Leg Platform (TLP) support system anchored with synthetic rope tendons attached to a gravity base template to provide a platform for a wide range of water depths with acceptable operating nacelle accelerations. In this paper, the NREL 5MW wind turbine is selected in order to provide a comparison to previous studies of steel tendon TLPs. A fully-coupled numerical modeling tool is used to assess the effects of extreme irregular sea loads on the TLP. A series of numerical simulations are carried out to compare the response of a Single Column (SC) TLP for three different water depths and three different environments. The responses are compared with the steel tendon model. The use of synthetic rope tendons potentially offers more efficient installation options and enlarges the range of acceptable water depths. The use of a gravity base/suction pile foundation may improve the installation cost and schedule. The fully coupled nonlinear, time domain analysis tool used provides a unique look into the fully operating wind turbine under stable motion characteristics of the TLP.

In Porter et al. (2011), we stated that "The EPRI effort is done-data are no longer being added to eSQUG…." This is incorrect. EPRI continues to investigate earthquakes and add data to eSQUG. We apologize for the error.