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In this study, it is demonstrated that hurricane wind intensity, forward speed, pressure, and track play an important role on the generation and propagation of coastal storm surges. Hurricane Irma, which heavily impacted the entire Florida peninsula in 2017, is used to study the storm surge sensitivity to varying storm characteristics. Results show that the west coast experiences a negative surge due to offshore wind of the approaching storm, but the positive surge returns after the hurricane eye passes over a location and wind became onshore. In the west coast peak, surges are intensified by an increase in onshore wind intensity and forward speed. In the Florida Keys, peak surges are intensified by an increase in wind intensity, a decrease in forward speed and a decrease in pressure. In southeast and east Florida, peak surges are intensified by decrease in pressure, although overall surges are less significant as the water can slide along the coastline. In the recessed coastline of Georgia-Carolinas, maximum surge is elevated by an increase in onshore wind intensity. Shifting the track westward increases peak surges on the west coast, while shifting the track eastward increases peak surge on the east coast. The results demonstrate a new understanding about the sensitivity of surge to varying parametric conditions and the importance of considering changes in the coastline orientation in storm surge predictions.
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Hydrodynamic Tests on Physical Models of Scaled Wood Frame Shear-Wall Residential Buildings
An on-grade and an elevated specimen were tested and exposed to regular waves, in the Directional Wave Basin (DWB) at Oregon State University, with varying water depths and wave heights to simulate typical wave/surge conditions resulting from landfall hurricanes on low-lying barrier islands such as Hurricane Sandy that impacted the US East Coast in 2012 and Hurricane Ike that impacted the US Gulf Coast in 2008. Several instruments were used in the experiment, including nine wire resistance wave gauges located offshore, eight ultrasonic wave gauges located onshore near the specimens, four acoustic-doppler velocimeters, twelve pressure sensors, four load cells, and four triaxial accelerometers located on the specimens. The data (water depth, wave height, velocity, pressure, force, acceleration) gathered can help engineers and numerical modelers better understand the wave-structure interaction and help in improving design criteria of coastal light wood frame residential structures subjected to hurricane overland surge and wave loading.
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- Award ID(s):
- 1661315
- PAR ID:
- 10304232
- Publisher / Repository:
- Designsafe-CI
- Date Published:
- Subject(s) / Keyword(s):
- Model_config_hydrodynamic_tests Sensor_info_hydrodynamic_tests Hydrodynamic_tests_without_structures hydrodynamic_tests_with_structures Relevant_documents_reports_hydrodynamic_tests Ohhwrl-Oregon
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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