<div>Architectured material systems offer the ability to control a system's response through the spatial arrangement of material. Material may be connected by discrete linkages or segmented by discrete cuts in such a system. This thesis serves as an investigation of the deformation and load response of architectured material systems in tubular configurations. Specifically, segmented tubes composed of interlocking building blocks and corrugated tubes formed from thin sheets of material are of interest.</div><div> </div><div>Interlocking, segmented tubes, or topologically interlocking material (TIM) tubes, are considered as assemblies of convex polyhedra. Multiple aspect ratios of tubes are considered with identical building block size. The load response to diametral indentation is obtained by finite element analysis and experimentation on additively manufactured tubes. Finite element models consider both an idealized scenario, where contacts between building blocks are stiff, and a realistic scenario, where there are much softer contacts between building blocks and a limit on shear stresses due to friction at contact interfaces. The mechanics of the deformation of TIM tubes are quantified by stress distributions and energies obtained from finite element models. It was found that interlocking between building blocks grants segmented systems increased stiffness, strength, and toughness. The response of TIM tubes varied with tube aspect ratio and contact conditions between blocks. An analysis of thrust-lines in the assembly with finite element results led to the formulation of a model to predict the load response of interlocking, segmented tubes. This model was found to fit idealized FE-model results, and, with the addition of slip between building blocks to the model, experiment results.</div><div> </div><div>Corrugated tubes are considered to be formed from stacks of sheet metal plies. Corrugations are formed one-by-one with a high-pressure fluid and forming machinery. The manufacturing process of these tubes is recreated in a finite element model. With this manufacturing model, the as-formed geometry and residual stress and strain profile of the tube are obtained. Finite element models of corrugated tube loading are created such that their initial state is the result of the manufacturing model. The response of corrugated tubes can then be investigated under the consideration of effects from manufacturing. Including the effects from manufacturing was found to influence the corrugated tube stiffness and yield force. Altering the ply thickness used to form tubes was also found to influence the corrugated tube stiffness. Certain fatigue failure locations were only predicted when including the effects from manufacturing in finite element simulations. Thus, the effects from manufacturing a corrugated tube were found to play a significant role in the tube's load response and failure.</div>

My art emerges from decades of the experience of building myself, sensitively aware of accumulated experience and the weight of accrued memory. Responding to this life I so deeply appreciate the longer I live, as sculptor, painter and poet, I merge these individual aesthetic observations into a layered work of many reads. Offering poetic observation as a visual sensation beyond the ears’ hearing carried on a field of color connects at some interior emotional level which is absent or very different in the uniformity of type. Time is present in my current work. “Corrugations”, not only in the poetic images emerging from three days in the embrace of nature but in the new task of the recycled cardboard of commerce as an agent of art. I share my observation of life as art objects of consideration, poetry embedded in the strong arms of bas relief sculpture, the abstract text of language make as visible as the emotional response to color. “Corrugations” becomes an environment where one can wander among the recycled attains a new nobility d offers sparse poems of human observation. Perhaps deceptively simple a certain richness exudes from the massed collection, two dozen glimpses into a state of mind at once impoverished and nourished by the vital power of wilderness. The machine of civilization has become almost a runaway train with a footprint greater than any natural cataclysmic act and we must create and foster a new state of balance within the biosphere. To value the promise of humanity is to seek to establish responsible civilization where the positive possibilities exist to cherish all forms of life. More important though is the nourishment of what human life could become as quality of all life becomes the most important and universal goal. To believe that growth is always a possible choice even in the midst of ancient negative behaviors which negate growth embracing positive change is perhaps less a luxury than a conscious personal choice and if my choice can inform consideration of choice in the viewer than my art has served well.

In the pursuit of economical and rapid fabrication solutions on the micro and nano scale, polymer replication has proven itself to be a formidable technique, which despite zealous development by the research community, remains full of promise. This thesis explores the potential of elastomers in what is a distinctly multidisciplinary field. The focus is on developing innovative fabrication solutions for planar photonic devices and for nanoscale devices in general. Innovations are derived from treatments of master structures, imprintable substrates and device applications. Major contributions made by this work include fully replicated planar integrated optical devices, nanoscale applications for photolithographic standing wave corrugations (SWC), and a biologically templated, optical fiber based, surface-enhanced Raman scattering (SERS) sensor. The planar devices take the form of dielectric rib waveguides which for the first time, have been integrated with long-period gratings by replication. The heretofore unemployed SWC is used to demonstrate two innovations. The first is a novel demonstration of elastomeric sidewall photolithographic mask, which exploits the capacity of elastomers to cast undercut structures. The second demonstrates that the corrugations themselves in the absence of elastomers, can be employed as shadow masks in a directional flux to produce vertical stacks of straight lines and circles of nanowires and nanoribbons. The thesis then closes by conceptually combining the preceding demonstrations of waveguides and nanostructures. An optical fiber endface is em ployed for the first time as a substrate for patterning by replication, wherein the pattern is a nanostructure derived from a biological template. This replicated nanostructure is used to impart a SERS capability to the optical fiber, demonstrating an ultra-sensitive, integrated photonic device realized at great economy of both time and money, with very real potential for mass fabrication.

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