This grant for Rapid Response Research (RAPID) will investigate the wind performance of agricultural storage silos and farm bins during the August 2020 Derecho. This high wind event left a path of structural damage exceeding 750 miles in length and crossing several Midwestern states, including Nebraska, Iowa, Illinois, and Indiana. This event presents a unique opportunity to evaluate the performance of agricultural storage silos and farm bins because of the unusually large area impacted in a predominantly agricultural region of the country and the wide range of wind speeds encountered (ranging from 60 – 130 mph). Despite the criticality of the agricultural industry to the U.S. economy and global food production, agricultural storage silos and farm bins have received relatively little attention with respect to natural hazards research. Furthermore, these structures are not designed to a consistent standard in the United States, which has led to a significant vulnerability in rural communities, and there is a critical need to understand the influence of design and construction parameters on the wind resistance of these structures. Findings from this study will advance fundamental knowledge regarding the performance of these structures in severe wind events and enable consideration of new design approaches and the evaluation of mitigation measures to safeguard U.S. food production and agricultural economies. Results generated in this project also will enable detailed studies of rural community resilience, which require an understanding of the unique structural typologies that comprise the built environment - a necessary step towards enhancing national resilience. This project will support a graduate student researcher, serving to train the next generation of STEM leadership, and will leverage an NSF-supported Research Experiences for Undergraduates Site to broaden participation of underrepresented groups in engineering. Data from this project will be archived and made publicly available in the NSF-supported National Hazards Engineering Research Infrastructure (NHERI) Data Depot (www.DesignSafe-ci.org) for broad use within the engineering community.
This RAPID grant seeks to answer fundamental research questions regarding the influence of key parameters on the wind resistance of agricultural storage silos and farm bins: (1) How do foundation type, anchorage depth (if present), and baseplate design influence the wind resistance of agricultural storage silos and farm bins?, and (2) How can the probability of failure for agricultural storage silos and farm bins be represented as a function of wind speed? These questions will be answered through a detailed investigation of the performance of agricultural storage silos and farm bins during the August 2020 Derecho. Specifically, perishable data will be collected documenting undamaged and damaged storage silos and farm bins in the path of the derecho. The team will document the design and construction of individual structures, estimated condition of the structure prior to the event, and current condition of the structure following the event. Aerial imagery and three-dimensional point clouds will be acquired for structures evidencing complex damage patterns. The typology and performance of nearby structures will also be documented to obtain more detailed estimates of wind speeds in the vicinity of the storage silos and farm bins. Data will be analyzed to generate empirical fragility curves to evaluate the influence of several design and construction parameters including foundation, anchorage, and baseplate design. The fragility curves can be used for subsequent research in rural community resilience.
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.
