INSTRUCTOR:  William L. Coulbourne, P.E., F.SEI, F.ASCE  

Purpose and Background

This webinar presents the information that is new in the ASCE 7-16 Commentary on tornado design. The latest research and wind committee deliberations were used in the development of the recommended tornado wind design methodology and are included for practitioner use. There is also a simplified method that has been developed as an alternate and this will also be presented. This webinar also discusses those issues regarding tornado design that have not been fully researched to give the attendee some idea about the level of uncertainty associated with tornado wind design.

This webinar introduces the subject of tornado wind design to an audience who is repeatedly asking for this design information. Tornado design and better resistance to tornado loads is a topic of high interest to the public, and thus to the design profession. The ASCE 7-16 Commentary was developed over the last ASCE 7 cycle of 6 years and uses the latest in tornado wind research as a basis for suggesting how the wind design parameters of ASCE 7 be modified to accommodate tornado winds. 

Primary Discussion Topics

• Wind design methodology recommended for use for tornado design
• Background in the differences recommended in the ASCE 7 wind speed parameters
• Presentation of a simple ASCE 7 alternate design method for tornadoes
• Information about uncertainties in the wind design parameters that are still being researched

Learning Outcomes

• Learn about the wind design parameters in ASCE 7-16 to use to calculate tornado wind pressures
• Become acquainted with the latest tornado research and how that research is helping develop improved tornado wind design
• Learn about the issues that are still unknown in tornado design and how these unknowns can still be considered
• Learn about a simplified method for determining tornado wind pressures that has been included in ASCE 7-16

Webinar Benefits

• Learn about the current thinking on designing for tornado wind loads as provided in the ASCE 7-16 commentary
• Reduce property losses from tornadoes
• Assist clients address tornado design issues, including building shelters in their facilities or homes
• Learn about what is still not well known about tornadoes and how to design for them to reduce lives lost and property damage
• Learn about the ongoing research into the area of tornado loads and constructed resistances

Intended Audience

Engineers involved in wind design for clients of any building type

Webinar Outline

• Background on tornadoes and suggested failure modes from damage investigations
• Tornado EF scale and how it is used
• ASCE 7-16 recommended wind design methodology for tornadoes
• Simplified method for tornado design
• Example comparative pressure results
• Wind-borne debris
• Performance-based design for tornadoes