The basic building blocks of nano-structured hierarchical cellular materials are nano-sized wires or plates. Due to the effects of surface elasticity and the initial stress/strain, their bending, torsion, stretching and transverse shear rigidities are not only size-dependent, but also tunable and controllable over a large range. Based on the closed form results of the bending, torsion, stretchi...

Simulating one-dimensional elastic objects such as threads, ropes or hair strands is a difficult problem, especially if material torsion is considered. In this paper, we present CORDE(french ’rope’), a novel deformation model for the dynamic interactive simulation of elastic rods with torsion. We derive continuous energies for a dynamically deforming rod based on the Cosserat theory of elastic ...

Grid-based methods for generating all-hex meshes show tremendous promise in automating and speeding up turnaround for computational simulations for solid mechanics. Recognizing some of its inherent weaknesses, there has been hesitancy in accepting this technology as a viable option for critical FEA. This study attempts to compare meshes generated with traditional manual pave-and-sweep technolog...

We characterize through large-scale simulations the nonlinear elastic response of multiwalled carbon nanotubes (MWCNTs) in torsion and bending. We identify a unified law consisting of two distinct power law regimes in the energy-deformation relation. This law encapsulates the complex mechanics of rippling and is described in terms of elastic constants, a critical length scale, and an anharmonic...

torsion of many symmetric structures, which were designed based on the seismic codes, is due to their asymmetricity induced during inelastic behavior. although the structure was designed symmetrically assuming elastic based criteria, different factors such as material inconsistency in structure, construction details discrepancy and construction errors may result in asymmetric behavior in inelas...

Left ventricular systolic torsion and diastolic recoil were quantified in 12 human cardiac transplant recipients with surgically implanted intramyocardial markers with the use of computer-aided analysis of biplane cineradiographic images. Measurements were performed between 6 and 16 weeks after surgery and related to the presence or absence of rejection as determined by cardiac biopsy. Torsiona...

Title of Document: MODELING RATE DEPENDENT DURABILITY OF LOW-AG SAC INTERCONNECTS FOR AREA ARRAY PACKAGES UNDER TORSION LOADS Vikram Srinivas, Master of Science, 2010 Directed By: Chair Professor, Michael G. Pecht, Department of Mechanical Engineering The thesis discusses modeling rate-dependent durability of solder interconnects under mechanical torsion loading for surface mount area array com...

We study the effects of thermal fluctuations on thin elastic filaments with spontaneous curvature and torsion. We derive analytical expressions for the orientational correlation functions and for the persistence length of helices and find that this length varies nonmonotonically with the strength of thermal fluctuations. In the weak fluctuation regime, the persistence length of a spontaneously ...

A theory for the size effect in the strength of wires under torsion is reported and compared with data from thin copper wires. Critical thickness theory is solved rigorously and used to validate a useful approximation which is combined with slip-distance theory modified for a finite structure size. Experimental data with high accuracy around and above the elastic limit show excellent agreement ...