This thesis works through the design process for a flood protection barrier falling within a special sub-category that the research team has defined: Sustainable Hybrid Bridge Barriers (SHBB). The design starts with what is known as a visor gate, which has some limited precedent around the world. But this project offers a unique new approach to that basic structure, which not only performs as a barrier in large storms, but also incorporates a pedestrian bridge, functions in a relatively more sustainable fashion, and has aesthetic appeal. The design process for each element of the barrier, including its unique ballast system, are worked through in the paper. Future work to be done to implement such a design in reality is also described systematically. The design on this iteration was unfortunately unsuccessful, but the groundwork has still been laid for next steps.

As the risks for coastal hazards increase, traditional countermeasures such as flood walls and storm surge barriers pose a problem, as they hinder access to the beach and diminish coastal beauty. A kinetic hypar umbrella has been proposed as an alternative solution that can provide hybrid benefits of coastal protection and structural art. While hydrostatic and hydrodynamic loads have been tested for the hypar geometry, wind loads have not yet been tested. This thesis seeks to understand the aerodynamic performance of the kinetic umbrellas under varying conditions of inclination and incidence angles. To do so, $CRUE20OWT$ (a wind tunnel at the Forrestal Campus of Princeton University) was validated by comparison with data sets collected at a vetted wind tunnel located at the University of Oviedo. Secondly, a velocity profile was measured for $CRUE20OWT$ to understand the variance in wind across the face of the nozzle. Both tests concluded that the difference between the data sets and the variance in the velocity profile was within the realm of testing errors to vet the wind tunnel, especially to study the behavior trends of the aerodynamic coefficients.

The impacts of changing inclination angles on drag and lift coefficients were observed to match the general behavior of airplane wings and its angle of attack. The drag and moment coefficient curves showed a U-shaped curvature with respect to inclination angles, which increased in value as the inclination decreased or increased away from 0 degrees. The lift coefficient showed a more sine-like curvature with a point symmetry about the 0 degrees point. With respect to the angle of incidence, the drag and moment coefficient curves also displayed a U-shaped curvature, increasing in value as the inclination decreased or increased away from 90 degrees. The lift coefficient exhibited a cosine-like curvature where the value decreases as the incidence angle increases from 0 and continues to decrease as the incidence angle increases to 180 degrees. The shape of the curvatures with respect to angle of incidence matches the expected behavior; changing the incidence angle rotation is essentially changing the angle of attack in another axis.

As global warming intensifies and climate change causes sea levels to rise in coastal communities, storm surge barriers are essential to protecting lives and property. Ideally, these structures would serve not only as emergency barriers but also have a secondary function, such as a pedestrian bridge for everyday use. This proposed dual-purpose concept is referred to as the Sustainable Hybrid Bridge-Barrier (SHBB) in this thesis. The objective of this thesis is to evaluate the aerodynamic wind coefficients and structural feasibility of a hybrid tube bridge-barrier structure. To do this, a design prototype was developed using Newtown Creek in NYC as the site, based on the NY-NJ HATS study. The minimum dimensions of the SHBB were determined by analyzing both site constraints and design code requirements. Inspired by existing tube bridges, several CAD models were created and 3D printed to test different design features in a wind tunnel. Three tube bridges were tested: one with no holes, and two with 25% porosity, one using smaller holes and the other using larger holes. A metal deck and printed arch were also tested in various combinations with the tubes. Wind tunnel results confirmed that adding porosity reduces the drag coefficient, with larger holes producing lower drag than smaller holes. The deck had little effect on drag and lift, while the arch had a significant impact. Without the arch, the lift coefficients were approximately zero. Drag coefficients ranged from approximately 1.2 to 1.5. As a result, the recommended tube bridge design should feature large perforations for reduced drag, a minimum diameter of 13 feet, and a conservative wall thickness of approximately 4 inches (assuming a steel material), though thinner sections may also be feasible.