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Recent major investments in infrastructure in the United States and globally present a crucial opportunity to embed equity within the heart of resilient infrastructure decision-making. Yet there is a notable absence of frameworks within the engineering and scientific fields for integrating equity into planning, design, and maintenance of infrastructure. Additionally, whole-of-government approaches to infrastructure, including the Justice40 Initiative, mimic elements of process management that support exploitative rather than exploratory innovation. These and other policies risk creating innovation traps that limit analytical and engineering advances necessary to prioritize equity in decision-making, identification and disruption of mechanisms that cause or contribute to inequities, and remediation of historic harms. Here, we propose a three-tiered framework toward equitable and resilient infrastructure through restorative justice, incremental policy innovation, and exploratory research innovation. This framework aims to ensure equitable access and benefits of infrastructure, minimize risk disparities, and embrace restorative justice to repair historical and systemic inequities. We outline incremental policy innovation and exploratory research action items to address and mitigate risk disparities, emphasizing the need for community-engaged research and the development of equity metrics. Among other action items, we recommend a certification system-referred to as Social, Environmental, and Economic Development (SEED)-to train infrastructure engineers and planners and ensure attentiveness to gaps that exist within and dynamically interact across each tier of the proposed framework. Through the framework and proposed actions, we advocate for a transformative vision for equitable infrastructure that emphasizes the interconnectedness of social, environmental, and technical dimensions in infrastructure planning, design, and maintenance.

From December 10 to December 11, 2021, a deadly tornado outbreak struck across several states in the US, including Arkansas, Illinois, Kentucky, and Tennessee. This tornado outbreak resulted in at least $3.9 billion in damage, more than 90 fatalities, and hundreds of injuries. Mayfield, Kentucky, a small city in the eastern United States, was hit by a long-track tornado rated as an Enhanced Fujita 4 (EF4) scale and was one of the communities most heavily damaged during the tornado outbreak. Following the 2021 tornado event, an analysis was performed in the Interdependent Networked Community Resilience Modeling Environment (IN-CORE) for the City of Mayfield to investigate a design code change for residential structures and its effect on communitywide metrics related to functionality and dislocation. Specifically, the IN-CORE modeling environment was used to hindcast the community-level building damage and forecast the community-level building recovery in Mayfield for residential buildings. This required the development of a Mayfield test bed for IN-CORE with a focus on buildings. The generalization of multidisciplinary community resilience modeling from a test bed community to a real community impacted by a recent major tornado event is intended to benchmark that IN-CORE has a strong potential and capability to forecast/hindcast community resilience and provide what-if scenarios for decision makers, city planners, and stakeholders in communities with similar sizes. [ABSTRACT FROM AUTHOR]

Tornado fatality rates in the southeastern United States are higher than those in Tornado Alley, despite Tornado Alley having a higher frequency of tornadoes. A major contributing factor is the large number of mobile and manufactured homes (MMHs) in the southeastern states. Forensic engineering assessments of tornado damage have consistently shown that inadequate anchoring of MMHs or the absence of proper anchoring has been the primary cause of structural failure. To properly design a MMH anchorage system to resist tornadic winds, it is imperative to have accurate knowledge of the tornadic wind effects on the MMH systems. In this study, tornado–MMH interactions are investigated using high-fidelity numerical simulations. The pressure distribution on the MMH surface and the total forces/moments on the entire MMH induced by tornadic winds are obtained. In addition, simulations are conducted to reveal (1) the difference in tornadic wind effects between a MMH and its associated permanent home (home with classical on-site construction), and (2) the difference in wind effects between tornadic winds and the equivalent straight-line winds. The latter of these comparisons is intended to provide information on the unconservative use of straight-line wind loading for MMHs. The simulation results (peak wind pressure and total forces/moments on the MMH) are compared between the tornadic wind field and straight-line wind field. The comparison indicates that the results caused by the tornado are higher. Under a tornadic wind field, compared with the permanent home (PH), the peak pressure and horizontal forces on the MMH are smaller because of the existence of open space under the MMH. Although the research findings here demonstrate the limitation of US code for MMHs, a great number of simulation cases with the related uncertainties involved will be needed to be run to improve the US code. [ABSTRACT FROM AUTHOR]

In this study, systematic numerical simulations are conducted to investigate how swirl ratio and radial Reynolds number affect the wind characteristics of multi-vortex tornadoes. By properly controlling boundary conditions, multi-vortex tornadoes are produced in a cylindrical computational domain. Six cases with different swirl ratios are studied to examine the influence of swirl ratio, while five cases with different radial Reynolds number are studied to investigate the influence of radial Reynolds number. To facilitate the characterization, the core size and rotational speed of subvortices, as well as the relative distance between the subvortex and the core radius of the main vortex, are defined. The results demonstrate that the increase in swirl ratio leads to the increase in the number of subvortices. For the overall vortex, the increase in swirl ratio decreases the maximum tangential velocity but increases the core radius of the overall flow. For subvortices, for the case where four subvortices are produced, the increase in swirl ratio increases the core size of subvortices but decreases the rotational speed of subvortices. While the increase in radial Reynolds number does not change the number of subvortices produced, it decreases the core size of subvortices, but increases the rotational speed of each subvortex. [ABSTRACT FROM AUTHOR]