Response Modification Factor for Inelastic Design of Low-rise Steel Moment Frame Buildings Subjected to Extreme Wind Loads
Author: Jonah W. Gocke
Publisher:
Published: 2020
Total Pages: 119
ISBN-13:
DOWNLOAD EBOOKThe current practice in wind resistant design in the United States is to proportion and detail the lateral force resisting system to remain elastic, even for extremely rare large-magnitude windstorms. In contrast, for seismic resistant design, the lateral force resisting system is allowed to exhibit controlled inelasticity and a reduced design force is used to provide a more economical structure. The objective of this study is to determine the applicability of inelastic design and a corresponding wind response modification factor for low-rise buildings subjected to extreme wind loads that use a steel moment frame lateral force resisting system. The hypothesis is that controlled inelastic behavior of the steel moment frame and ductile detailing could justify a reduced design force for wind applications, similar to the approach used for seismic applications. To test the hypothesis, archetype buildings (a 3-story office building and a 1-story industrial/retail “Big Box” building) were designed for four wind speeds, 110-mph, 127-mph, 156-mph, and 220-mph. This study focuses on the 1-story building. Four types of moment frames with varying levels of ductility implemented into their design were then subjected to a dynamic wind load and the non-linear responses were analyzed and compared. The results indicate that controlled inelasticity can justify a reduced wind design force for the 1-story moment frame building investigated in this study. Further study, including a wider array of building archetypes and wind load directions, is required to determine the appropriateness of inelastic design and a corresponding wind response modification factor for broader application.