Presentation: ASCE NC Fall Conference

Predictive Multi-Hazard Hurricane Data-Based Fragility Model for Residential Homes

Multi-hazard hurricane data-based fragility models are able to represent multiple predictor variables, be validated based on observed data, and consider variability in building characteristics and hazard variables. This paper develops predictive hurricane, multi-hazard, single-family building fragility models for ordered categorical damage states (DS) and binary complete failure/non-complete failure using proportional odds cumulative logit and logistic regression models, respectively. In addition to their simplicity, these models are able to represent multiple hurricane hazard variables and include variable interactions, thus improving model fitting and damage prediction. Surveys of physical damage in coastal Mississippi following Hurricane Katrina (2005) and high-resolution numerical hindcast hazard intensities from the Simulating WAves Nearshore and ADvanced CIRCulation (SWAN + ADCIRC) models are used as model input. Prediction accuracy is expressed in terms of cross-validation (CV) and evaluated using leave-one-out cross-validation (LOOCV).

Thirty-nine combinations of global damage response variables were investigated. Of these models, six DS and one complete failure model met the evaluation criteria. Maximum significant wave height was the only significant hazard variable for the DS models, while maximum 3-s gust wind speed, maximum surge depth, and maximum water speed were found to be significant predictors for the complete failure model. Model prediction external accuracy ranged from 81% to 87%.

CC Massarra, CJ Friedland, BD Marx, JC Dietrich (2019). “Predictive Multi-Hazard Hurricane Data-Based Fragility Model for Residential Homes.” Coastal Engineering, 151, 10-21, DOI: 10.1016/j.coastaleng.2019.04.008.

Visitors from Johnson C Smith University to CCHT

Fourteen students (and four faculty members) in CRC’s JCSU Summer Research Program visited our Department of Civil, Construction, and Environmental Engineering. The students shared presentations about their research projects, and then learned about computing- and resilience-related opportunities at NC State. This program is supported by the DHS Coastal Resilience Center of Excellence.

Dr. Dietrich poses with JCSU students and faculty outside of Mann Hall.

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PREEVENTS Project Meeting in Chicago

Several CCHT members visited Chicago to meet with collaborators from Notre Dame on our NSF PREEVENTS project. The meeting was held in the Chicago campus of the Notre Dame College of Business, located on Michigan Avenue in downtown. Despite the great views from the venue, we had a productive meeting!

Johnathan Woodruff, Zachariah Silver, Casey Dietrich, Autumn Poisson, Andrew Kennedy, Amirhosein Begmohammadi, Thomas Sherman, and Dam Wirasaet.

News: Dietrich Promoted to Associate Professor

2019/06/03 – NCSU Civil, Construction, and Environmental Engineering
Faculty Promotions

ncsu-engr

We are pleased to announce that we have had several faculty promoted during this year in recognition of their excellent contributions to research and teaching.

Dr. Casey Dietrich was promoted to Associate Professor with tenure. Dietrich, who leads the Coastal and Computational Hydraulics Team has developed computational models that predict storm surge and coastal flooding. He teaches courses in fluid mechanics and coastal engineering.

Conference: ADCIRC 2019

Analytic Solution for Wind-Driven Setup

In their manuscript “Analytic Solutions for Computer Flow Model Testing,” Lynch and Gray present solutions for water levels and depth-averaged velocities, for tidal and/or wind forcing, and for Cartesian and polar domains. These solutions have been useful for model validation, especially for tides, and especially within the ADCIRC community — the first example problem in the ADCIRC documentation is based on one of their solutions. That problem, for tidal flows in a polar domain, has been used to validate several model advancements over the years.

However, we found an error in their solution for wind-driven setup on a polar domain. It appears to be a typographical error — the variables are not updated correctly at the last step, when the solution is generalized for a wind with arbitrary direction. This solution is not used frequently, and we did not find a correction to this error in the literature (although we were unable to access every subsequent manuscript that cited the Lynch and Gray solution). So we are documenting it here.

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