information about design parameters on the existing record drawings. Considerations such as the cost of improvement recommendations ver- sus building a new facility and determining the time needed to execute the project presented another layer of challenge. While there are several FEMA reference standards and building codes that provide guidance on the various challenges described above, it is anything but a straightforward process to unify all of that and come up with a systematic, cost-effective solution that can be rapidly employed. Standardizing the site-specific data collection process involved inter - viewing several long-tenured TxDOT employees in a short time. Often, that was the only way to get information about past performance of the facilities during extreme events, past repairs/retrofits/renovations, and existing hurricane and flood preparedness plans. Another challenge was classifying the asset integrity for hurricane/ wind and flood in a way that can be easily understood by the local TxDOT employees and upper management, while also being consis- tent with the applicable building codes and FEMA reference standards. Most of the mainstream media reporting of the environmental hazard events pertaining to hurricane and flood relates to Saffir-Simpson Hur - ricane Category for hurricane/wind and 100 year or 500-year classifi - cations for flood events. For engineering analysis and design, building codes and FEMA reference standards do not directly correlate to those mainstream media narratives. Picture a building built in 1939 which is long beyond its service life and has gone through several re-roofing exercises still standing but not in sync with current code requirements. Coming up with recommenda- tions to improve its resiliency against future hurricane/wind and flood events without making extensive retrofits or building a new facility from the ground up was a major undertaking. Systematic Evaluation Three teams of assessors comprising professional engineers and ar- chitects were employed for this project. The three assessment teams utilized a field reconnaissance checklist, which was incorporated into the report section of each building. Teams were assembled with a bal- ance of skills to address identification and documentation of building assemblies, structural components, and critical infrastructure. To gather necessary facilities data, the assessment team first reviewed available site plans and building drawings. Assessment teams then conducted site visits to all 52 buildings in the five coastal districts. The work performed at each site included: • Discussion with local staff to explain the facility evaluation and inquire about historic storms, protective shutters, generators, and the existence of drawings, if not provided previously. • Verification, documentation, and measurement of exterior en - velopes, including walls and roofs, if accessible. • Exploration of accessible attics, mezzanines, and roofs to verify and document structural components.
A correlation was made between Saffir-Simpson Hurricane Wind Scale and hurricane/wind resiliency level determined based on the building codes. Illustration is provided in the images below.
Saffir-Simpson hurrican wind scale
Also, a correlation was made between a 100-year flood event, a 500- year level flood event and the flood resiliency level determined based on the building codes. Illustration is provided in the image below. Approximate relationship between Saffir-Simpson hurricane scale & ASCE 7
Costal storm surge and correlation with building code resiliency
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october 2021 csengineermag.com
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