Deployable Hyperbolic Paraboloidal Umbrellas as Adaptable Aquatecture for Coastal Defense Applications

Abstract

This dissertation presents a radical rethinking of conventional coastal armor via the development of “Kinetic Umbrellas” inspired by the architecture of master builder Félix Candela. Unlike traditional floodwalls or levees which rely on sheer mass alone, Kinetic Umbrellas are remarkably thin shells that utilize the double curvature of hyperbolic paraboloids (hypar) to resist surge and wave forces associated with landfalling tropical cyclones. As a kinetic structure, these umbrellas only deploy into an impermeable barrier prior to imminent hazard scenarios but remain a canopy during normal weather such that beach access is not impeded. The aforementioned notions of architectural elegance, geometric efficiency, and social adaptability are formally unified to synthesize the philosophy of “Adaptable Aquatecture” in the context of coastal hazard engineering. Owing to its unique geometry, a decoupled numerical scheme constituting smoothed particle hydrodynamics (SPH) and finite element modeling (FEM) was leveraged for the structural analysis of deployed Kinetic Umbrellas under arbitrary hydrodynamic forcing. Experimental validation of the SPH-FEM technique took place by means of dam-break testing on 3D-printed umbrella specimens. By mapping the spatial distribution of fluid forces computed via SPH onto Kinetic Umbrellas created through FEM, it was revealed that the effects of double curvature dramatically reduces out-of-plane stresses that typically limit the performance of thin shells. As such, a 100 mm thick concrete umbrella covering 64 m2 can successfully resist over 7 m of hydrostatic inundation matching its entire deployed height. Hydrodynamic modeling subsequently confirmed that Kinetic Umbrellas proved structurally viable against surge inundation and wave attack consistent with Hurricane Sandy (2012) at Monmouth Beach, NJ. Finally, in deriving the theoretical kinematics of hypar umbrellas, a novel mechanism for their safe and rapid deployment without compromising aesthetic appeal was developed. Ultimately, through the exemplification of Adaptable Aquatecture via Kinetic Umbrellas, this work illustrates how historical (heritage) forms can inspire socially conscious solutions to modern structural engineering challenges imposed by climate change.