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Showing 1 to 13 of 13 for “"buckling instability"”.
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Lateral-Torsional Buckling Instability Caused by Individuals Walking on Wood Composite I-Joists
… loads and are susceptible to lateral-torsional buckling instability. Workers walking on unbraced or partially braced wood I-joists can induce axial and lateral forces as well as twist. Experimental testing demonstrated that workers cause lateral-torsional buckling instability in wood I-joists. …
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Mechanics of planar periodic microstructures
… into the voids in specified patterns. A local buckling instability in the square lattice and shear instability in the hexagonal lattice trigger the change in pattern in the structure upon reaching a critical stress during compression. Experimental and numerical results are obtained that show …
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Postbuckling Analysis of Delaminated Composite Plates Under Compression (Composite Laminates)
… The failure modes in general may include prebuckling, postbuckling, delamination growth and final failure. Buckling load is determined by solving an eigenvalue problem using a subspace iteration technique. The Riks-Wempner iterative scheme is then used to determine the associated postbuckling …
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ULTRA-LOW K DIELECTRIC MATERIALS WITH HIGH BREAKDOWN STRENGTH AND EXCELLENT MECHANICAL PROPERTIES
… properties using strain-induced elastic buckling instability measurement for mechanical property measurements (SIEBIMM). The breakdown strength of nearly 3.2 GV/m, which is higher than linear polymers. The permittivity values range from 1.7 to 1.2, which is the lowest among any known …
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Interplay of flow and microstructure in complex fluids: Semiflexible polymer solutions and emulsions
… and assume highly bent configurations, due to a buckling instability. A theory to predict the onset of strong buckling is presented; according to this theory, worm-like polymer molecules transition from rod-like to flexible-like behavior. The theory is verified by Brownian dynamics, which show a …
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Nanomechanical Properties of Polymer-Grafted Nanoparticle Ultrathin Films
… evaluated through strain-induced elastic buckling instability for mechanical measurements (SIEBIMM) technique. This study was further extended by blending the PMMA-g-SiO2 nanoparticles at 5 %wt. loading to block copolymer (BCP) matrix (PS-b-PMMA) (45-b-48 kg/mol) to investigate the effects …
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Fabrication of silicon-based nano-structures and their scaling effects on mechanical and electrical properties
… from 7 to 18. During indentation, a buckling instability was observed at a critical load, followed by a displacement burst without a load increase, then a fully recoverable deformation upon unloading. For experiments with larger indentation displacements, irrecoverable indentation …
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Morphology and mechanical properties of electrospun polymeric fibers and their nonwoven fabrics
… a wrinkled morphology that can be explained by a buckling instability. Understanding which structures and morphology form under a given set of conditions is achieved through the comparison of three characteristic times: the drying time, the buckling time and the phase separation time. The …
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Dynamics of single semiflexible filaments in a viscous fluid
… in the compressional regime, filaments undergo a buckling instability similar to Euler buckling of beams, taking on higher mode shapes with increasing flow strengths. Both suppression and buckling are attributed to a competition between tension and elasticity. Our study confirms the existence of …
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Physical ecology of marine microbes
… We found that marine bacteria can exploit a buckling instability of their flagellum to change direction during swimming, achieving the same functionality as multi-flagellated cells, but with the cost of synthesizing and operating only one flagellum. This finding not only reveals a new role of …
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Ordering of Nanoparticles by Wrinkle-Assisted Self-Assembly : Controlling Plasmonic Coupling Effects
… Additionally, wrinkles fabricated through a buckling instability of a stiff supported layer under compression are not tension free on the microscopic level and suffer from relaxation on a longer time scale. We introduce in this work two different methods to replicate wrinkles by molding. In …
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Design and testing of fiber-constrained electroactive polymer
Soft robotics take advantage of active materials to regenerate many complex motions, including low-force functions, such as camouflage, micro-grabbing, or agile locomotion of micro robot. For these applications, traditional actuators, like electric motors and combustion engines, are unnecessarily …