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Seismic Design of Rigid Wall-Flexible Diaphragm Buildings

Cover photo for the document: Seismic Design of Rigid Wall-Flexible Diaphragm Buildings

Single-story buildings with rigid walls and flexible diaphragms (RWFD buildings) are common throughout the United States and are often used for warehouse buildings and “big box” retail stores. These buildings have stiff walls constructed of reinforced concrete or masonry, or braced frames of structural steel, and relatively flexible diaphragms of metal deck or wood structural panels. The seismic response of this type of structure is dominated by the deformation of the large and relatively flexible diaphragms. The standard design methods used in current seismic codes for all building types, however, assume primary response occurs in deformation of the vertically oriented lateral force resisting elements—moment frames, braced frames, or shear walls. A design approach for the RWFD building type that is more technically correct than current code design methods, and that can be shown to meet accepted code performance, has been sought for some time.

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Icon for file of type application/pdfSeismic Design of Rigid Wall-Flexible Diaphragm Buildings: An Alternate Procedure (FEMA P-1026)

This FEMA NEHRP document is a new design resource that applies recent research and testing results to address the seismic performance issue of “big box” buildings. This type of buildings is typically used for warehouses or retail stores and has been reported for numerous earthquake damage or collapses in the past.

0.02GMarch 1, 2015