MAYFIELD, KENTUCKY

On December 10-11, 2021, a deadly tornado struck several U.S. states, including Arkansas, Illinois, Kentucky, and Tennessee, resulting in $3.9 billion in damage, more than 90 deaths, and hundreds of injuries. Mayfield, KY was one of the most heavily damaged communities. More than 3,778 residential buildings (typically single-family dwellings), 183 commercial properties, and 103 other buildings were damaged or completely destroyed (NOAA 2021)[1]. 

Mayfield’s City Lead Recovery Coordinator, Ryan Drane, requested an analysis to help support their resilience planning from the Center for Risk-Based Community Resilience Planning (referred to as the Center of Excellence or CoE) funded by the National Institute of Standards and Technology. 

The CoE used IN- CORE’s modeling environment to hindcast the community-level building damage in Mayfield for residential buildings to explore how a different building codes or policies could have decreased housing damage and decreased population dislocation.

Step 1: Create a model in IN-CORE that is reflective of Mayfield’s building structures and design model of the EF4 tornado wind fields based on historical data and recreate the approximate the 2021 tornado path in Mayfield. 

Step 2: Run damage analysis based on existing building stock and document the damage. 

Step 3: Include proposed changes to building code (provided by R. Drane) and update residential buildings with specific levels of strength, stiffness, and performance and re-run the simulation and damage analysis. 

Step 4: Provide Mayfield with a comparison of damage analyses with and without proposed changes to building code to support decisions on changes in building code. 

Comparisons of damage (figures 1 and 2) with dark blue indicating the greater chance that buildings will become nonfunctional.

Figure 1. Probability of Non-functional Buildings under Current Building Design for an EF4 tornado, showing greater risk of building destruction 

Figure 2. Probability of Non-functional Buildings under Proposed Building Design for an EF4 tornado, showing improvements in functionality >

The graph on the right shows the total number of buildings in the path of the simulated EF4 tornado shown in figures 1 and 2, and the resulting number of buildings rendered nonfunctional under current design and under improved building designs.

Analysis indicates a 24% reduction in nonfunctional buildings under improved building codes after an EF 4 tornado, resulting in 62% of buildings becoming nonfunctional, versus 86% under current design. Comparisons of damage (figures 1 and 2) with dark blue indicating a greater chance that buildings will become nonfunctional.

[1] Department of Commerce, NOAA. 2021. “The Violent Tornado Outbreak of December 10-11, 2021.” National Weather Service, NOAA’s National Weather Service, https://www.weather.gov/pah/December-10th-11th-2021-Tornado. [2] Wang, L., van de Lindt, J.W., etc. 2023. Community Testbed Model to Support Potential Structural Design Code Changes: The 2021 U.S. Midwest Tornado Outbreak. 

Disaster Prevention and Resilience (under review)