Steel Structures Research Update: Steel Diaphragm Innovation Initiative

The Steel Diaphragm Innovation Initiative (SDII) is a multiyear academic-industry partnership to advance the seismic performance of steel floor and roof diaphragms in steel buildings is highlighted. The team includes AISC T.R. Higgins Lectureship Award and AISC Milek Fellowship Award winners for topics ranging from developments in long-span composite slabs to buckling-restrained braced frames to continuity plate detailing for steel moment-resisting connections. The team’s motivations for creating SDII stemmed from issues with respect to the knowledge base for steel diaphragm performance, codes and standards, as well as missed opportunities for advancements in seismic performance-based design. The available research on steel diaphragms was primarily focused on the strength of isolated systems; little was known about ductility or whole-building performance. The team developed a five-year case and plan to “advance the seismic performance of steel floor and roof diaphragms utilized in steel buildings through better understanding of diaphragm-structure interaction, new design approaches, and new three-dimensional modeling tools that provide enhanced capabilities to designers utilizing steel diaphragms in their building systems” (SDII, 2017). The work includes providing research support for much-needed revisions to proposed seismic codes and standards for steel diaphragms. SDII is also working on innovative steel diaphragm solutions for efficient, robust and resilient steel building systems.