Manufactured homes, or prefabricated homes, are attractive due to their affordability and can be transported anywhere, making them ideal for seasonal housing. While they are more robust than their predecessors, mobile homes, they are vulnerable to major storm damage, particularly strong hurricane winds. While wind does play a major role, how they’re secured to the ground is also a factor that relates to weaknesses in anchorage and load path continuity. Researchers Pedro J. Marquez, Elaina J. Sutley, William Collins, and Thang Dao wanted to better understand how manufactured homes were impacted by Hurricane Michael, which hit the Florida Panhandle in 2018.
Their study, “Performance of Manufactured Home Anchorage Systems after Hurricane Michael,” examines the persistent structural vulnerability of manufactured homes when exposed to hurricane-force winds. Using field observations, the authors examined how the anchors were installed, how they interacted with the soil, and what kinds of failures occurred. By comparing observed performance with expected design behavior, the study highlights key patterns in anchorage performance, including where systems met expectations and where they fell short. Learn more about this research and how you can apply these lessons to refine anchorage specifications, improve quality control during installation, and enhance risk assessment for manufactured housing communities in the Journal of Performance of Constructed Facilities at https://ascelibrary.org/doi/10.1061/JPCFEV.CFENG-5309. The abstract is below.
Abstract
Manufactured homes (MHs) are frequently damaged during hurricanes, highlighting the need for structural improvements to enhance their resilience. This concern is especially critical given their dual role as both post-disaster temporary housing and long-term affordable housing. One of the key structural components contributing to the stability of MHs under wind loads is the anchorage system, which resists uplift and lateral forces. Despite their vital role in maintaining structural integrity during extreme weather events, research on anchorage systems remains limited. The extreme conditions of 2018 Hurricane Michael, where sustained winds exceeded 258 km/h (160 mph), provided an ideal scenario for evaluating the performance of MH anchorage systems. This study utilizes post-disaster damage data collected after Hurricane Michael to evaluate the performance of MH auger anchorage systems. Displacement measurements are taken on post-disaster imagery where anchors are visible for a collection of MHs, primarily located in Wind Zone II. The findings align with existing literature, confirming that auger anchors underperformed during Hurricane Michael, failing to meet codified working loads at the required displacements. Although anchors can prevent catastrophic failure, excessive displacement was observed under wind pressures below design thresholds, indicating a risk of foundation compromise in stronger wind events. This study highlights the vulnerability of MHs to high-wind conditions and underscores the need for targeting mitigation strategies, particularly to enhance the anchorage system. Additionally, this study provides an updated perspective on anchor performance and offers recommendations to enhance wind resistance and overall structural resilience in manufactured housing.
Explore the researchers’ findings and applications that can improve anchorage resilience for manufactured housing in the ASCE Library: https://ascelibrary.org/doi/10.1061/JPCFEV.CFENG-5309.
