NEESR-SG: Smart and Resilient Steel Walls for Reducing Earthquake Impacts

University Of Washington, Seattle WA

Investigators

Abstract

This award is an outcome of the NSF 08-519 program solicitation, "George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research (NEESR)" competition and includes the University of Washington (lead institution), University of Minnesota (subaward), and University at Buffalo, SUNY (subaward). This project will utilize the NEES equipment sites at the University of Minnesota and University at Buffalo and has strong international collaboration with large-scale experiments to be performed at the National Center for Research in Earthquake Engineering (NCREE) in Taiwan. The goal of this project is to develop a smart and resilient steel plate shear wall (SR-SPSW) system with the potential to transform seismic design in areas of moderate and high seismicity. The system strategically combines the benefits of self-centering and steel plate shear wall technologies to create a robust, ductile, and easily repairable system that will reduce life-cycle costs for buildings. Most traditional seismic load resisting systems will suffer structural damage during seismic events; the cost and downtime associated with repair of that damage has led to staggering economic losses. The proposed SR-SPSW system could drastically reduce those losses. SPSWs are excellent candidates for the application of self-centering technology; they have high strength and elastic stiffness and require low re-centering forces. The buckling and yielding behavior of the web plate will also be leveraged to develop self-sensing concepts such that post-event decisions regarding web plate replacement can be made with minimal disruption. SPSW behavior under earthquake loading is highly nonlinear, and complex component interactions exist; of particular complexity are the interactions between the web plate tension field action and the forces in the re-centering mechanisms of the proposed SR-SPSWs. Large-scale testing using advanced experimental techniques and instrumentation will generate data to be used to develop numerical models anchored in physical behavior. Application of those tools in parametric analyses of SPSW systems will provide a new level of understanding of the system response and help to eliminate overly conservative design processes. To ensure that the new SR-SPSW system will be implemented, and to increase the use of conventional SPSW systems, this research will also seek to fill critical knowledge gaps in SPSW system behavior including the understanding of coupled SPSW behavior and the expected distribution of yielding in multistory SPSW. The project also includes a series of activities that will advance the NEES education, outreach, and training goals. Through collaboration with Seattle-MESA, the project will engage high school students from underrepresented minorities in structural engineering and laboratory experimentation, ultimately helping to promote diversity in engineering and science. The project team also includes faculty and undergraduates from Seattle University, a predominantly undergraduate institution, who will contribute to the research endeavor. The project will excite K-5 students about science and engineering through the development of the Wicked Walls program; a hands on learning activity showing students the benefits of walls for seismic resistance. Finally, outreach to practicing structural engineers will occur through the Seismic Provisions committee, conference presentations, and seminars with the cooperation of AISC. The research team experience in developing national and international codes ensures that research outcomes will have an immediate impact on design practice. Data from this project will be made available through the NEES data repository (http://www.nees.org).