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Research led by the Precast/Prestressed Concrete Institute (PCI) has been honored with an American Society of Civil Engineers (ASCE) Charles Pankow Award for Innovation. The project, “Seismic Diaphragm Seismic Design Methodology (DSDM),” was also funded by the National Science Foundation (NSF) and the Network for Earthquake Engineering Simulation (NEES).
Representing literally groundbreaking research conducted by engineers and precast concrete industry experts, the project involves a comprehensive seismic design methodology for precast concrete diaphragms. Its development involved integrating finite element analyses of a diaphragm with full-scale reinforcing detail experiments and shaking table system tests. This initiative resulted in the adoption of a revised force demand and resistance methodology for precast concrete diaphragms in the 2015 National Earthquake Hazards Reduction Program (NEHRP) and ASCE/Structural Engineering Institute (SEI) 7-16, Minimum Design Loads For Buildings and Other Structures. (The complete research report is available here, on the “Completed Projects and Programs” tab.)
“This project was successfully completed because of exceptional collaboration between academia and industry,” said PCI’s vice president of technical services, Roger J. Becker, PE, SE. “Its completion and codification of the results means engineering professionals can now use precast concrete diaphragms with confidence in any seismic zone.”
Features of the performance-based seismic design methodology include:
- diaphragm seismic design forces that more accurately reflect the actual inertial forces during strong shaking;
- more rational methods of determining diaphragm internal forces;
- inelastic deformation capacity requirements for the diaphragm reinforcement;
- protection of potentially non-ductile elements in the precast concrete diaphragm though capacity design concepts; and
- explicit inclusion of diaphragm flexibility in drift limits checks.
A multi-university research team from the University of Arizona, Lehigh University, and the University of California San Diego (UCSD) was selected to perform the collaborative research.
