RAPID: Performance of Agricultural Storage Silos and Farm Bins in Nebraska and Iowa During the August 2020 Derecho

这项快速反应研究（RAPID）拨款将在2020年8月Derecho期间调查农业储存筒仓和农场垃圾箱的风力性能。这场强风造成了超过750英里长的结构性破坏，并穿越了几个中西部州，包括内布拉斯加州、爱荷华州、伊利诺伊州和印第安纳州。这一事件提供了一个独特的机会来评估农业储存筒仓和农场垃圾箱的性能，因为在该国主要的农业地区受到影响的面积非常大，而且遇到的风速范围很广（从60 - 130英里/小时）。尽管农业对美国经济和全球粮食生产至关重要，但农业储存筒仓和农场垃圾箱在自然灾害研究方面受到的关注相对较少。此外，在美国，这些建筑物的设计标准并不一致，这导致农村社区的严重脆弱性，因此迫切需要了解设计和施工参数对这些建筑物抗风能力的影响。这项研究的结果将推进有关这些结构在强风事件中性能的基础知识，并使人们能够考虑新的设计方法和评估缓解措施，以保护美国的粮食生产和农业经济。该项目产生的成果还将有助于对农村社区的复原力进行详细研究，这需要了解构成建筑环境的独特结构类型-这是加强国家复原力的必要步骤。该项目将支持一名研究生研究员，以培养下一代STEM领导力，并将利用NSF支持的本科生研究经验网站，扩大代表性不足的群体在工程中的参与。该项目的数据将在NSF支持的国家灾害工程研究基础设施（NHERI）数据库（https：//www.example.com）中存档并公开提供，供工程界广泛使用。www.DesignSafe-ci.org该RAPID赠款旨在回答有关关键参数对农业储存筒仓和农场仓的抗风性的影响的基础研究问题：（1）基础类型，锚固深度（如果存在）和底板设计如何影响农业储存筒仓和农场仓的抗风性？以及（2）如何将农业储存筒仓和农场仓的失效概率表示为风速的函数？这些问题将通过对2020年8月Derecho期间农业储存筒仓和农场垃圾箱性能的详细调查来回答。具体而言，将收集易腐数据，记录在derecho路径上未损坏和损坏的储存筒仓和农场垃圾箱。该团队将记录单个结构的设计和施工、事件发生前结构的估计状况以及事件发生后结构的当前状况。将为证明复杂损坏模式的结构获取航空图像和三维点云。还将记录附近结构的类型和性能，以获得对储存筒仓和农场垃圾箱附近风速的更详细估计。将对数据进行分析，以生成经验脆弱性曲线，从而评估几个设计和施工参数（包括基础、锚固和底板设计）的影响。脆弱性曲线可用于农村社区恢复力的后续研究。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

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 (https://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.