CAREER: Impact of Green Roof and Vertical Greenery Systems on Structural Performance for Multi-Hazard Scenarios

San Francisco State University, San Francisco CA

Investigators

Abstract

This Faculty Early Career Development (CAREER) award will contribute to the resilience and capacity of communities to address climate change and recover from natural hazard events, such as earthquakes, by producing a novel design approach for green infrastructure (GI) (i.e., green roof and vertical greenery structures) to decrease monetary losses, deaths, and downtime associated with these events. Sustainable structures with GI are needed to tackle climate change. This research will address a critical gap in resources for practicing engineers and users of buildings with GI in regions with seismic/wind risk with a set of applied guidelines for weight variations of GI, including associated demands at various moisture content levels for optimal structural performance. The educational plan includes an educational video series on sustainable structural resilience for undergraduate and graduate students and research experiences for five university student assistants from underrepresented groups. Further, open access to research results, design guidelines, and new educational materials will inform civil engineering students in the California State University system, practicing civil engineers in the U.S., and public consumers to increase sustainability efforts and decrease negative impacts of climate change and natural hazard events. Data generated from this project will be made publicly available in the National Science Foundation (NSF)-supported Natural Hazards Engineering Research Infrastructure Data Depot (https://www.DesignSafe-CI.org). This award supports the NSF role in the National Earthquake Hazards Reduction Program. The goal of this award is advance knowledge on GI’s sensitivities, influences on structural behavior, and potential as a mitigation strategy. There is an established need to characterize structural response as a combined effort between sustainable and resilient design because the increase in GI usage over the past several decades has outpaced research to support the engineering community in its design efforts. The project’s research objectives include: (1) quantification of structural behavior distributions due to changes in the GI from natural hazards (i.e., drought, storm surge), natural growth, and other life-cycle factors (i.e., poor maintenance); (2) development of an initial design strategy for increased seismic performance; and (3) creation of a transformative set of design guidelines for sustainable structures considering GI variabilities. This will be achieved through sensitivity analyses of modal behavior and testing of a strategic GI plan using nonlinear time history analyses for a seismic scenario. The educational goals are to train the next generation of civil engineers to understand sustainable building designs with new, open-access educational materials and to inform practicing civil engineers and the public about the positive impacts of sustainability efforts that decrease the negative impacts of climate change and wind/seismic events. Informing and building engineering confidence in GI design will: (1) increase structural resilience with improved designs, modeling, and analysis procedures; (2) reduce the human/economic costs associated with structural failure; and (3) increase the use of GI while promoting sustainability. 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.