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Post-disaster field observations of the built environment are critical for advancing fundamental research that links hazard data to structural performance, cascading community impacts, and the development of effective mitigation strategies. Yet, data collection remain fragmented across hazard types and infrastructure systems due to varying objectives, methodologies, protocols, and standards among investigators and organizations. To address this, a Unified Assessment Framework has been developed for standardized post-disaster hazard and structural assessment data and metadata collection across multiple natural hazards (earthquake, windstorm, coastal events) and infrastructure typologies. The framework encompasses a tiered performance assessment structure with increasing rigor and fidelity levels: Basic Assessment (BA), Load Path Assessment (LPA), and Detailed Component Assessment (DCA). The framework has been implemented as an open-access mobile application, the Structural Extreme Events Reconnaissance (StEER) Network’s StEER Unified App, hosted on Fulcrum data collection platform . Along with unification of data fields, preliminary mapping rules were developed to map out existing hazard-specific damage rating scales (e.g., wind, surge/flooding, rainwater ingress) to the European Macroseismic Scale (EMS-98) compatible unified damage scale, enabling consolidation of global damage ratings into a common data field, facilitating the unification of multiple hazards within a single app. In the mapping of damage ratings, overarching level definitions were retained (e.g., slight, moderate, severe damage) while customizing the specific descriptors to reflect hazard-specific damage mechanisms. Two use cases are presented to demonstrate the application of this framework through the StEER Unified App: a supervised pilot after the 2022 Hurricane Ian, Florida and an unsupervised deployment for the 2023 Turkey earthquake sequence. These deployments illustrate the framework’s flexibility and scalability, validate the feasibility of standardized assessments, and offer insights into how data quality is influenced by assessor pre-deployment training and assessment tier—particularly for complex tasks such as load path evaluation. This work advances the field by providing a scalable, standardized, and hazard-agnostic approach to structural field reconnaissance. The open-access framework and app support real-time deployments and enable integration of legacy datasets into a unified platform—laying the foundation for longitudinal analyses, cross-hazard comparisons, and expanded data reuse in the Natural Hazards Engineering community. 

Eighteen years after Hurricane Charley made landfall in 2004, Hurricane Ian made landfall in nearly the same location, also as a Category 4 hurricane. Unlike Hurricane Charley (2004), water more so than wind was the impetus behind the disaster that unfolded. Despite being a below-design-level wind event, the large windfield drove a powerful storm surge as much as 13 ft high (relative to the NAVD8 vertical datum) in the barrier islands of Sanibel, Ft. Myers Beach, and Bonita Beach. Flooding was extensive along not only the Florida coast, but also well inland into low-lying areas as far north as Duval County and the storm’s second landfall site in South Carolina. As such, Hurricane Ian will likely be one of the costliest landfalling hurricanes of all time in the US, claiming over 100 lives. The impacts from Hurricane Ian were most severe in the barrier islands from the combination of storm surge and high winds, with many buildings completely washed away, and others left to deal with significant scour and eroded foundations. Several mobile/manufactured home parks on the barrier islands fared particularly poorly, offering little to no protection to anyone unfortunate enough to shelter in them. The damage was not restricted to buildings, as the causeways out to the barrier islands were washed away in multiple locations. In contrast, wind damage from Hurricane Ian appears less severe overall relative to other Category 4 storms, perhaps due to a combination of actual wind intensity being less than Category 4 at the surface at landfall, and the improvements in building construction that have occurred since Hurricane Charley struck 18 years earlier. It is notable that extensive losses were in part driven by decades-long construction boom of residential structures in Ft. Myers and Cape Coral since the 1950s and 1960s, expanding communities and neighborhoods encroaching upon vulnerable coastlines. Beyond serving as an important event to validate current and evolving standards for coastal construction, Hurricane Ian provides a clarion call to reconsider the ramifications of Florida's coastal development under changing climate. This project encompasses the products of StEER's response to this event: Preliminary Virtual Reconnaissance Report (PVRR), Early Access Reconnaissance Report (EARR) and Curated Dataset. 

Abstract Disasters provide an invaluable opportunity to evaluate contemporary design standards and construction practices; these evaluations have historically relied upon experts, which inherently limited the speed, scope and coverage of post-disaster reconnaissance. However, hybrid assessments that localize data collection and engage remote expertise offer a promising alternative, particularly in challenging contexts. This paper describes a multi-phase hybrid assessment conducting rapid assessments with wide coverage followed by detailed assessments of specific building subclasses following the 2021 M7.2 earthquake in Haiti, where security issues limited international participation. The rapid assessment classified and assigned global damage ratings to over 12,500 buildings using over 40 non-expert local data collectors to feed imagery to dozens of remote engineers. A detailed assessment protocol then conducted component-level evaluations of over 200 homes employing enhanced vernacular construction, identified via machine learning from nearly 40,000 acquired images. A second mobile application guided local data collectors through a systematic forensic documentation of 30 of these homes, providing remote engineers with essential implementation details. In total, this hybrid assessment underscored that performance in the 2021 earthquake fundamentally depended upon the type and consistency of the bracing scheme. The developed assessment tools and mobile apps have been shared as a demonstration of how a hybrid approach can be used for rapid and detailed assessments following major earthquakes in challenging contexts. More importantly, the open datasets generated continue to inform efforts to promote greater use of enhanced vernacular architecture as a multi-hazard resilient typology that can deliver life-safety in low-income countries. 

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. 

Remote reconnaissance missions are promising solutions for the assessment of earthquake-induced structural damage and cascading geological hazards. Space-borne remote sensing can complement in-field missions when safety and accessibility concerns limit post-earthquake operations on the ground. However, the implementation of remote sensing techniques in post-disaster missions is limited by the lack of methods that combine different techniques and integrate them with field survey data. This paper presents a new approach for rapid post-earthquake building damage assessment and landslide mapping, based on Synthetic Aperture Radar (SAR) data. The proposed texture-based building damage classification approach exploits very high resolution post-earthquake SAR data integrated with building survey data. For landslide mapping, a backscatter intensity-based landslide detection approach, which also includes the separation between landslides and flooded areas, is combined with optical-based manual inventories. The approach was implemented during the joint Structural Extreme Event Reconnaissance, GeoHazards International and Earthquake Engineering Field Investigation Team mission that followed the 2021 Haiti Earthquake and Tropical Cyclone Grace. 

This project contains imagery collected from uncrewed aircraft system (UAS) flights over three barrier islands, Fort Myers Beach (FMB), San Carlos (SC), and Sanibel Island (SI), that are near Fort Myers, Florida, following Hurricane Ian. These barrier islands had substantial impacts from the hurricane, including the destruction of many residences and infrastructure, coastal degradation, and other environmental impacts. The imagery here was collected using a low-flying fixed-wing UAS with a high-resolution camera system that simultaneously collected oblique and nadir images from five lenses. The raw data set is very comprehensive and very dense. The extent of the collected data can be seen in the Hazmapper map. The data was processed into 3D models using structure from motion. The resulting 3D models have amazing damage detail and are measurement quality. They can be used to fully characterize damage to buildings, infrastructure, and the natural environment. The complete models are available here, with one model developed for each UAS flight (18 total flights). However, the complete models are very large data sets and require significant GPU power to open and manipulate. Thus, the data set is also divided into “tiled” areas on a 300-meter grid. Each tiled area is provided in both a full-resolution 3D model and a reduced-resolution preview that can be used for quick inspection. The tiles are named and distributed as shown here: https://arcg.is/19TLr5. The abbreviations for Fort Myers Beach (FMB), San Carlos (SC), and Sanibel Island (SI) are used throughout. The data set was collected and processed by the NHERI RAPID Facility and was part of the deployment by the Structural Engineering Extreme Events Reconnaissance Network (StEER). 

The COVID-19 era has witnessed numerous successful and unsuccessful attempts to adapt or reconfigure physical, virtual, and hybrid aspects of the built environment in order to mitigate the risks of co-occuring (i.e., compound) hazards. But it has also witnessed major challenges to ensuring that the protections these reconfigurations afford are equitably distributed. Additional theoretical and empirical research is needed to inform transitions (via adaptive reconfiguration) toward short-term goals of health and well-being, as well as to guide transformations (via the establishment of stable configuration) toward longer-term goals of equitable societal function. To this end, this paper presents a framework for conceptualizing adaptation of the built environment as a series of state transitions in response to (or in anticipation of) compound hazards. It draws upon cases from recent experience in the areas of food production, shelter, and education to critique, clarify, and explicate this framework. It concludes with implications for further research on the management of transitions in the built environment under a range of hazard scenarios.