Statistical Analysis of a Three-dimensional Axial Strain and Axial-shear Strain Elastography Algorithm. (August 2011) Mohan Li, B.S., University of Science and Technology of China Chair of Advisory Committee: Dr. Raffaella Righetti Pathological phenomena often change the mechanical properties of the tissue. Therefore, estimation of tissue mechanical properties can be of clinical importance. Ult...

In this paper, the equivalent linearization method with a weighted averaging proposed by Anh (2015) is applied to analyze the transverse vibration of quintic nonlinear Euler-Bernoulli beams subjected to axial loads. The proposed method does not require small parameter in the equation which is difficult to be found for nonlinear problems. The approximate solutions are harmonic oscillations, whic...

The objective of this paper is to quantify how nanoscale surface stresses impact the critical buckling strains of silicon nanowires. These insights are gained by using nonlinear finite element calculations based upon a multiscale, finite deformation constitutive model that incorporates nanoscale surface stress and surface elastic effects to study the buckling behavior of silicon nanowires that ...

ABSTRACT: In this study, large-deformation and small-strain elasto-plastic analysis of space frames with symmetric cross sections and semi-rigid connections are presented. The effect of axial forces on the bending moment and lateral buckling are included. However, axial-torsional and warping effects are omitted. The Eulerian equations for a beam-column with finite rotation taking into account b...

General thermo-mechanical behavior of composites reinforced by shape memory alloy fibers is predicted using a three-dimensional analytical micromechanical method to consider the effect of fibers activation. Composite due to the micromechanical method can be exposed to general normal and shear mechanical and thermal loading which cause to activate the shape memory alloy fibers within polymeric m...

In this paper, the off-axis tensile behaviors of triaxial woven fabric reinforced rubber composites (TWFR) was studied experimentally and numerically. The failure morphologies stress-strain curves specimens cut at seven different angles (0°, 15°, 30°, 45°, 60°, 75°, 90°) were obtained by finite element analysis experiment. results found to be in good agreement with experimental results. Stress-...

In this paper, we develop a theoretical expression for the signal-to-noise ratio (SNR) of shear strain elastograms. The previously-developed ideas for the axial strain filter (ASF) and lateral strain filter (LSF) are extended to define the concept of the shear strain filter (SSF). Some of our theoretical results are verified using simulations and phantom experiments. The results indicate that t...

This study focuses on the biaxial mechanical properties of planar aorta tissue at strain rates likely to be experienced during automotive crashes. It also examines the structural response of the whole aorta to longitudinal tension. Twenty-six tissue-level tests were conducted using twelve thoracic aortas harvested from human cadavers. Cruciate samples were excised from the ascending, peri-isthm...

The strain-temperature behavior of Ni-Ti samples upon martensitic phase transformation was investigated as a function of applied uniaxial tensile and compressive stresses. Axial and transverse strains were measured. The samples were fabricated from stock bars of powder metallurgical origin. They were machined into tubes or solid bars with square cross sections. The tubular samples were cycled i...

  In the current work, the seismic analysis of bent region in buried pipes is performed, and effects of soil properties and modeling methods on pipe’s response are investigated. To do this task Beam, Beam-Shell Finite Element modeling and a Continuum shell FE models of a 90 degrees elbow are employed. In the Beam model, the pipe is simulated by beam elements while combined shell-beam elements a...