Preliminary Assessment of Wind- and Storm Surge-Induced Residential Building Damage Caused By Hurricane Harvey (2017)

Hurricane Harvey was the first of three major hurricanes in 2017 to generate devastating impacts in the US. The concomitant hazards of wind, rainfall and storm surge caused significant structural damage to residential buildings in Aransas County and Refugio County in coastal Texas, with wind damage extending as far inland as approximately 100 mi. Ground-based damage surveys were conducted two days and approximately one month after landfall to evaluate the performance of residential structures in regions immediately impacted by Harvey. Over one thousand ground-based assessments were recorded between both ground surveys, augmented by aerial- and ground-based imagery shared by other field teams and stakeholders. This robust building performance dataset has been coupled with hazard intensity observations from an extensive network of federal, industry and academic partners, and parcel-level building attributes provided by the impacted counties. Given the plethora of building attribute, building performance and hazard intensity data available for analysis, there is a unique opportunity to comprehensively study the fragility of residential buildings in the region immediately impacted by Harvey, and improve our understanding of the major factors contributing to the fragility.

This study aims to create preliminary wind, storm surge and joint wind-storm surge fragility functions for residential buildings near Rockport, Texas. To create the fragility functions for residential buildings, the hazard information and building performance data from aerial- and ground-based imagery will be quality controlled using descriptive statistics and a standard damage rating framework. Once the data are quality controlled, it will be aggregated to examine single hazard- and joint hazard-damage relationships. Segregations into different building construction eras will then be conducted to examine the performance of older residential structures relative to newer construction. Finally, a comparison to existing damage models will be made to determine how well they predict residential building damage relative to the newly created fragility models.