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Although organizations build housing in resource-limited contexts after typhoons and other disasters that is intended to be safer than what existed previously, the performance of these houses in future typhoons—and the factors influencing performance—are unknown. This study develops a component-level, performance-based wind engineering assessment framework and evaluates the wind performance of twelve semi-engineered post-disaster housing designs, representing thousands of houses that were constructed in the Philippines after Typhoon Yolanda. We found that roof panel loss likely occurs first for most designs, at wind speeds equivalent to a category 2 hurricane/signal 3 typhoon. Roof shape determines whether this loss is caused by failure at the panel-fastener interface or purlin-to-truss connection. However, houses with wooden frames and woven bamboo walls may also experience catastrophic racking failures at wind speeds equivalent to signal 2 or 3 typhoons, a situation exacerbated by strengthening the roof. Results also show that wind performance varied with roof shape, component spacing, panel thickness, eave length and connection between purlin and truss. Organizations can use these results to improve housing performance, taking specific care to increase wall capacity. This framework can be expanded to assess housing performance in other resource-limited contexts.There is an urgent need to improve community capacity to recover more effectively after disasters through safer design and construction practices. To do this, training programs need to foster an improved understanding of shelter design and construction to withstand future wind and earthquake events. This project analyzed informal builders’ perceptions of housing safety in Puerto Rico (responding to 2017's Hurricane Maria and the 2019-2020 earthquake swarm) and homeowner’s perceptions of housing safety in Philippines (responding to 2013's Typhoon Haiyan and 2017's Ormoc earthquake) to: (1) assess local understanding of shelter safety in multiple hazards, including causal factors influencing this understanding, through a household survey in the Philippines and a survey to informal contractors in Puerto Rico; (2) assess the expected performance of various post-disaster shelter typologies to quantify safety during future earthquake and wind events using performance-based engineering methods, developing a rapid screening tool that can be used in design or evaluation; (3) identify conflicts between perceived and assessed safety of shelter, and why these conflicts exist, by comparing engineering assessments with local perceptions; and (4) create a communication design for organizations assisting with training for safer housing construction.
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Informally-Constructed houses in Puerto Rico under Hurricane load:Building Capacity for Safer Post-disaster Shelter: Leveraging Local Understanding and Advanced Engineering Assessments
This study assesses the wind performance of various housing typologies representing informal construction practices in Puerto Rico to suggest modifications to enhance housing resilience in hurricanes. Based on fieldwork and interviews, the study defined four base housing typologies and possible variations in design and construction details. Each house was assessed using performance-based static wind analysis of potentially critical components. The results show that the initial governing failure mode in all base house typologies considered is roof panel loss due to tear-through at the fasteners, with subsequent governing failures being panel loss due to failures at the purlin-to-truss connections and failures of the truss-to-wall connections. In-plane wall failures and masonry uplift failures were both found to occur at much higher wind speeds than roof failures. To improve the hurricane performance, several feasible modifications are suggested, including installing hurricane straps at both the truss-to-wall and the purlin-to-truss connections, as well as improving the panel-fastener interface. In the construction of new roofs, this study found that using reduced spacing between roof members, hip roofs instead of gable roofs, and higher roof slopes leads to improved performance. These recommendations can make houses built through informal construction processes safer and more resilient to hurricanes as a form of climate adaptation.There is an urgent need to improve community capacity to recover more effectively after disasters through safer design and construction practices. To do this, training programs need to foster an improved understanding of shelter design and construction to withstand future wind and earthquake events. This project analyzed informal builders’ perceptions of housing safety in Puerto Rico (responding to 2017's Hurricane Maria and the 2019-2020 earthquake swarm) and homeowner’s perceptions of housing safety in Philippines (responding to 2013's Typhoon Haiyan and 2017's Ormoc earthquake) to: (1) assess local understanding of shelter safety in multiple hazards, including causal factors influencing this understanding, through a household survey in the Philippines and a survey to informal contractors in Puerto Rico; (2) assess the expected performance of various post-disaster shelter typologies to quantify safety during future earthquake and wind events using performance-based engineering methods, developing a rapid screening tool that can be used in design or evaluation; (3) identify conflicts between perceived and assessed safety of shelter, and why these conflicts exist, by comparing engineering assessments with local perceptions; and (4) create a communication design for organizations assisting with training for safer housing construction.
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- Award ID(s):
- 1901808
- PAR ID:
- 10498502
- Publisher / Repository:
- Designsafe-CI
- Date Published:
- Subject(s) / Keyword(s):
- PR-Hurricane-Model PR-Hurricane-Input PR-Hurricane-Output PR-Hurricane-Analysis PR-Hurricane-Report
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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