April Tucson Chapter Lunch Meeting
Shake Table Test Performance of an Inertial Force-Limiting Floor Anchorage System
by Dr. Robert B. Fleischman
A new floor connecting system is being developed for low-damage seismic-resistant building structures. The system, termed an Inertial Force-Limiting Floor Anchorage System (IFAS) is intended to limit the seismic forces in buildings during an earthquake. This objective is accomplished by providing low-strength deformable connections between the floor system and the primary elements of the lateral force resisting system. The connections transform the seismic demands from inertial forces to relative displacement of the floors, thereby dissipating the earthquake energy. This talk describes the IFAS performance in a shake table testing program that provides a direct comparison with an equivalent traditional “rigidly-anchored floor” structure. The testing program followed extensive analytical research to optimize the IFAS design properties, culminating in the development of an IFAS prototype using state-of-the-art components. The test structure is a half scale four-story reinforced concrete flat plate shear wall structure. Precast hybrid rocking walls and special precast columns were used for test repeatability for a 22 strong motion sequence. The structure was purposely provided with an eccentric wall layout to examine the performance of the system in coupled translational-torsional response. The test results indicated a seismic demand reduction in the IFAS structure relative to the traditional structure, including lower shear wall base rotation, shear wall and structure column inter-story drift, and accelerations. These results indicate the potential for the IFAS to minimize structural and non-structural damage during earthquakes.
Biographical Sketch of
Dr. Robert B. Fleischman
Dr. Robert B. Fleischman is a Professor, and formerly the Delbert R. Lewis Associate Professor, in the Civil Engineering and Engineering Mechanics Department at the University of Arizona. Dr. Fleischman’s research area is seismic resistant design and resilience of precast/prestressed concrete and steel structures with recent projects including the development of new low-damage seismic-resistant building systems, evaluation of water pipe systems, and developing a new design methodology for precast concrete floor diaphragms. The latter work will be included in new design provisions approved for inclusion in the ASCE 7-16 Load Standards and Part 3 of the 2015 National Earthquake Hazards Reduction Program (NEHRP) Recommended Provisions for Seismic Design for New Buildings. Dr. Fleischman has industry experience at Turner Construction (NYC), Thornton-Tomasetti (Chicago) and Rutherford & Chekene (San Francisco). Dr. Fleischman has won several national awards for his research including the 2016 American Society of Civil Engineers (ASCE) Charles Pankow Award for Innovation, the National Science Foundation (NSF) 2014 NEES Outstanding Contributor Award, and the Precast/Prestressed Concrete Institute (PCI) 2014 Leslie D. Martin Award of Merit, the 2009 and 2004 Martin P. Korn Awards, the 2006 Charles C. Zollman Award, and 2004 George D. Nasser Award. Dr. Fleischman has led earthquake reconnaissance teams to Haiti and New Zealand. Dr. Fleischman has also won teaching awards at the University of Arizona seven times in the past decade.
Please register by Monday April 17, 2017
Roasted Chicken Quarters, served with potato salad and garden salad. Brownie Bite for dessert. Water or iced tea.
Should you have any special dietary needs, please contact Ali Nessaee at Alvandengineers@gmail.com to coordinate.