Abstract

Evidence indicates that the dynamic behavior of Rigid Wall - Flexible Diaphragm (RWFD) buildings is dominated by the flexible roof diaphragm’s response instead of the walls’ response, and this is a significant departure from the underlying assumptions of the widely used equivalent lateral static force methods in current building codes. RWFD buildings are common in the Americas and other parts of the world, and incorporate rigid in-plane concrete or masonry walls and flexible in-plane wood or steel roof diaphragms. In an effort to improve the seismic performance of this common building type, the National Institute of Building Sciences (NIBS) directed this study to develop a new design methodology that is simpler and more rational than current practice. With the use of a nonlinear numerical computer modeling framework developed specifically for this type of building, an investigation following procedures of the Federal Emergency Management Agency (FEMA) publication P695 was conducted across a wide range of RWFD archetype designs developed under the 2012 International Building Code and the Minimum Design Loads for Buildings and Other Structures, ASCE/SEI 7- 10, for both moderate and high seismic exposures.

In this project, a new design procedure was developed that improves building performance by acknowledging the different vibrational periods and levels of available ductility in rigid walls and flexible roof diaphragms. Additionally, through encouraging distributed yielding across the diaphragm span, the performance of flexible wood roof diaphragms was found to improve their collapse resistance. This new procedure’s methodology is proposed to be implemented into the design codes of the United States (US) as an alternative seismic design approach for this type of structure, and is included in Part 3 of the 2015 National Earthquake Hazard Reduction Program (NEHRP) Recommended Seismic Provisions for New Buildings and Other Structures (FEMA P-1050-2). Additionally, the FEMA P1026 publication that resulted from this project provides background, illustrative commentary and design examples of this alternative procedure.

Disciplines

Architectural Engineering

Number of Pages

12

Publisher statement

© IAEE. All rights reserved. E-ISSN 3006-5933

Download

Share

COinS
 

URL: https://digitalcommons.calpoly.edu/aen_fac/176