Lights from hotels, homes, and other buildings can confuse the turtles into heading the wrong way. Natural light at the horizon guides the hatchings to the ocean. Another threat comes from coastal development. Females dig a hole in the sand, then deposit their clutch of eggs (up to 100, in the leatherback’s case), cover it back up, then return to the sea.Īfter about 60 days, the eggs hatch and tiny hatchlings make their way from the nest to the water at night, often a deadly ordeal as seabirds, crabs, and other predators prey on the young turtles. Sea turtles mate at sea, then come ashore on beaches to lay their eggs. The leatherback travels an average of 3,700 miles each way. Sea turtles make incredibly long migrations between feeding and breeding areas. Photograph by David Doubilet, Nat Geo Image Collection Turtle journeys These findings are size independent and can serve as initial guidelines in the development of new architectured materials for toughness.A critically endangered hawksbill sea turtle hatchling paddles away from shore in Cuba. These models show that periodic architectures can achieve higher toughness when compared with random microstructures, the toughest architectures are also the most anisotropic, and tessellations based on brick and mortar are the toughest. We identified several toughening mechanisms including crack deflection, crack tortuosity, crack pinning, and process zone toughening. We explored crack propagation and fracture toughness in Voronoi-based tessellations (to represent intergranular cracking in polycrystalline materials), tessellations based on regular polygons, and tessellations based on brick-and-mortar. In this study, we used the discrete element method (DEM) to explore the fracture mechanics of several hundreds of 2D tessellations composed of rigid “tiles” bonded by weaker interfaces. While their architecture can serve as inspiration for the design of new synthetic materials, a systematic exploration of architecture-property relationships in architectured materials is still lacking. Interestingly, natural materials such as seashells, bones, or teeth make extensive use of this strategy. The interplay between the architecture of the materials and the interfaces between the blocks can be tailored to control the propagation of cracks while maintaining high stiffness. In dense architectured materials, stiff building blocks of well-defined size and shape are periodically arranged and bonded by weak but deformable interfaces. Journal of Verification, Validation and Uncertainty QuantificationĪrchitectured materials contain highly controlled structures and morphological features at length scales intermediate between the microscale and the size of the component.Journal of Thermal Science and Engineering Applications.Journal of Offshore Mechanics and Arctic Engineering.Journal of Nuclear Engineering and Radiation Science.Journal of Nondestructive Evaluation, Diagnostics and Prognostics of Engineering Systems.Journal of Nanotechnology in Engineering and Medicine.Journal of Micro and Nano-Manufacturing.Journal of Manufacturing Science and Engineering.Journal of Engineering Materials and Technology.Journal of Engineering for Sustainable Buildings and Cities.Journal of Engineering for Gas Turbines and Power.Journal of Engineering and Science in Medical Diagnostics and Therapy.Journal of Electrochemical Energy Conversion and Storage.Journal of Dynamic Systems, Measurement, and Control.Journal of Computing and Information Science in Engineering.Journal of Computational and Nonlinear Dynamics.Journal of Autonomous Vehicles and Systems.ASME Letters in Dynamic Systems and Control.ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part B: Mechanical Engineering.Mechanical Engineering Magazine Select Articles.
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