CURRENT AND PAST: GEOMETRY AND ELASTICITY IN CIVIL-SCALE SHELLS AND MEMBRANES UNDER EXTREME LOADING
Civil-scale shells and membranes are non-linear redundant systems: they share their loading throughout the surface and can thus aid in preventing progressive collapse.Because of their curved geometry (and sometimes their elastic straining), they acquire additional geometric and elastic stiffness under increased loading. This phenomenon is indeed of great structural benefit and totally unprecented in comparison with other structural systems.
Yet a lot remains unknown about the response and optimum design of these surface structures under extreme loading. Our overarching goal is to create analytical formulations, numerical form finding, optimization, fluid/structure interaction models and machine-learning techniques and prototypes that capture the behavior (both linear and nonlinear, including instability) of membranes, nets, flexible and rigid shells (both continuous and lattice). We advance the field by offering an enhanced understanding of these structures systems with respect to 1) geometry and elasticity; 2) nonlinear mechanics; 3) instabilities and 4) response to extreme loading.
We have investigated in great detail the following applications for the built and natural environment: 1) rigid shells and arches and seismic loading, 2) semi-flexible shells and environmental stresses (solar radiation), 3) flexible nets and wavebreak loading, 4) pressurized membranes and storm surge loading, 5) flexible suspension and trussed bridges and pedestrian loading and 6) deployable scissor bridges.
The knowledge we generate, advances the fields of solid mechanics, dynamics, lightweight structure design and can be adopted in other large-scale structures (e.g. protective tsunami barriers) to achieve better resilience for a wide range of natural and manmade hazards.