Abstract
The Structural Engineering Institute (SEI) has a long history of working with NIST and other federal partners to improve ASCE/SEI 7 Minimum Design Loads and Associated Criterial for Buildings and Other Structures, the national loading standard. Following the Joplin, Missouri tornado of 2011, NIST investigated the event and published their recommendations Technical Investigation of the May 22, 2011, Tornado in Joplin, Missouri (NIST 2014), to improve the understanding of the climatology of tornadoes and development of design standards for the tornado hazard. Recommendation No. 5 from this report is as follows: "Recommendation No. 5: NIST recommends that nationally accepted performance-based standards for tornado-resistant design of buildings and infrastructure be developed and adopted in model building codes and local regulations to enhance the resiliency of communities to tornado hazards. The standards should encompass tornado hazard characterization, performance objectives, and evaluation tools. The standards shall require that critical buildings and infrastructure such as hospitals and emergency operations centers be designed to remain operational in the event of a tornado." This recommendation was assigned to ASCE, particularly SEI. This recommendation led to the development of the first set of tornado design provisions in the world, in the 2022 edition of ASCE/SEI 7. This workshop identified the next steps in the development of the standard provisions and performance objectives for performance-based design procedures. The workshop brought together many of the leading experts in tornado climatology, interaction with the built environment, the design of structures for tornadoes, and community resilience to evaluate the current societal needs, and to further our understanding of the tornado hazard. The workshop identified a broad range of research and development activities to advance the standardization of tornado design provisions with the goal of reducing the impacts of these severe wind events. This report includes discussion of research needs in multiple areas and specific recommendations on the following 10 priority research needs identified by the workshop participants: 1. Community Resilience Goals for Tiers of Functionality. 2. Tornado-Borne Debris. 3. Improved Characterization of Tornado Flow Fields. 4. Mean Recurrence Interval (MRI) and Target Reliabilities for Tornadoes vs Straight –line Wind. 5. Improvement of Tornado Windspeed Estimation Methods. 6. Standards for Tornado Simulators. 7. Tornado effects on Building Internal Pressures for Design. 8. Existing Buildings Standards for Evaluation and Retrofit for Wind. 9. Combine Atmospheric Pressure Change with External Pressure Coefficients; and 10. Tornado Storm Shelter Design Standards for Mechanical Components. This workshop report is also available for download from ASCE at
https://ascelibrary.org/doi/book/10.1061/9780784485828