Dual System Strongback Designs for Seismic Damage-Resistant Structures

University Of Tennessee Knoxville, Knoxville TN

Investigators

Abstract

Strongback systems are a new design strategy for structural systems that can mitigate the concentrated accumulation of structural damage in buildings during an earthquake. Despite their promising potential to improve performance during seismic events, strongback systems have not seen widespread use in new construction because insufficient data exist to document and characterize their behavior and functionality. The goal of this research is to investigate and quantify how different elements and configurations of strongback systems contribute to the resilience of buildings to earthquake damage and to determine how best to incorporate those features into future designs. The increased fundamental understanding of strongback systems, the developed optimal design methodology, and predictive equations will help structural engineers to design structures with strongback systems and encourage the further use of these systems. The results will enable the construction of buildings that are better able to withstand extreme seismic events, increase the safety of the public, and provide a basis for more efficient construction practices that will increase prosperity and reduce environmental impact. Additionally, through this project, undergraduate research assistants and a graduate student will be engaged and trained in numerical and experimental research methods. The small-scale, modular experimental strongback model developed as a result of this research will be used as the basis for hands-on learning activities in graduate courses. Project data will be archived and disseminated through the NSF-supported Natural Hazards Engineering Research Infrastructure (NHERI) Data Depot (https://www.DesignSafe-ci.org), filling a need for high-quality system level data for strongback system model validation. This award supports the National Earthquake Hazards Reduction Program. This research will fill gaps in the fundamental knowledge of the performance of strongback seismic force-resisting systems and will enable design methodologies that consider and exploit the complexities of the nonlinear dynamic response of these systems. New data will be generated on the demands that "elastic" elements of structural systems attract, the consequences of approaching or exceeding the strength of such elements, and the distribution of energy dissipating resistance. The potential of innovative devices, such as those that feature inertance, to tune the dynamic behavior of building structures will be demonstrated. Optimization within the large and unexplored design space opened by the strongback system will guide and inspire future studies on these systems. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.