Barbara Simpson, Ph.D. - US grants

Post-earthquake reconstruction efforts in New Zealand, Chile, and Japan are motivating the development of novel, low damage lateral force resisting systems to minimize social disruptions and property damage. These efforts, combined with earthquake scenarios highlighting seismic risks to cities in the United States, have led U.S. agencies to focus on increasing urban resilience against future extreme events by defining performance goals in terms of post-earthquake re-occupancy and functional recovery metrics. In parallel, non-profit organizations are driving the use of more sustainable building materials and construction practices. This project will create a new design paradigm within structural engineering that employs multi-objective optimization to maximize post-earthquake functional recovery while integrating sustainable building practices into the design process. The new design paradigm will be applied to the design and construction of resilient mass timber structural systems. The novelty of mass timber construction and limited availability of codes and standards make it uniquely positioned to pioneer innovative structural systems and new design paradigms, such as incorporating multi-objective optimization. The unique design paradigm developed in this project is called "converging design," as the methodology will be better able to converge across competing life-safety, post-earthquake functional recovery, and environmental sustainability objectives. The research will be complemented by an outreach program that includes training of the next generation of industry and academic leaders and fosters increased partnerships among academia, industry, building code officials, and government agencies. In addition, the research will lead to several undergraduate student experiences in STEM through an institutional Research and Extension Experiences for Undergraduate Student program and collaborations with NSF-funded Research Experiences for Undergraduates sites. This project will support the National Science Foundation (NSF) role in the National Earthquake Hazards Reduction Program.

The goal of this project is to integrate functionality-based design and multi-objective optimization into a single converging design paradigm that will support resilient, sustainable seismic solutions for lateral force resisting systems. The project will integrate existing and new data from laboratory and numerical work to (1) define functional recovery and sustainability metrics, including quantification of uncertainty, for the design of innovative lateral force resisting systems employing mass timber spine solutions; (2) create and implement a multi-objective optimization converging seismic design methodology that considers resiliency and sustainability goals; and (3) develop optimized seismic lateral force resisting systems, whose performance is validated through a six-story full-scale building test program at the NSF-supported Natural Hazards Engineering Research Infrastructure (NHERI) outdoor shake table at the University of California, San Diego (UCSD). The six-story specimen re-uses an existing ten-story shake table specimen that will be tested on the UCSD shake table in 2021/2022. A series of expert elicitation interviews and participatory workshops will support the definition of resiliency metrics, including time to functionality and sustainability metrics (e.g., embodied carbon) to meet the goal of the research. Educational modules for industry and higher education will be created. An industry working group will promote increased collaboration and foster innovation among academia, industry, and government agencies. This project will lead to new seismic design possibilities and advance knowledge of the functionality and sustainability of mass timber structures based on decades of research in seismic design, advances in high-performance computing that support optimization in design, and functional-recovery modeling, including sustainability goals. Project data will be archived and made publicly available in the NHERI Data Depot (https://www.designsafe-ci.org).

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.