The effect of stitching on mode I and mode II strain energy release rates for debond configurations is studied using an analysis based on plate finite elements and the virtual crack closure technique. The stitches were modeled as discrete nonlinear fastener elements with a compliance determined by experiment. The axial and shear behavior of the stitches was considered with both the compliances ...

Elastography involves tracking the ultrasonic A-mode signals before and after mechanical compression of tissue to form a computed image of the local strains undergone by various tissue components. The quality of the strain estimates in elastography is typically quantified using factors such as the elastographic SNR (SNR(e)), contrast-to-noise ratio (CNR(e)), and the spatial resolution. These qu...

by Nathaniel T. Hollingsworth Annulus fibrosus damage has been shown to come from combinations of bending, lifting, and twisting. Although the these motions can induce annulus fibrosus damage, the stress-strain state of the annulus during these motions is not known. The objective of this project was to develop more complete constitutive models and to investigate annulus fibrosus damage mechanic...

The influence of compressive and tensile axial strains on the critical current of various NhgSn conductors is investigated. The investigated multifilamentary wires are especially developed for the ITER project. The critical current is determined as a function of an axial tension in a standard pull set-up. These results are compared with the results that are obtained on a bending spring-type str...

In this paper, homotopy perturbation and modified Lindstedt-Poincare methods are employed for nonlinear free vibrational analysis of simply supported and double-clamped beams subjected to axial loads. Mid-plane stretching effect has also been accounted in the model. Galerkin's decomposition technique is implemented to convert the dimensionless equation of the motion to nonlinear ordinary differ...

linear dynamic response of simply supported nanobeams subjected to a variable axial force is assessed by galerkin numerical approach. constitutive behavior is described by three functional forms of elastic energy densities enclosing nonlocal and strain gradient effects and their combination. linear stationary dynamics of nanobeams is modulated by an axial force which controls the global stiffne...

In this research, using the Modified Compression Field Theory (MCFT), a new model is proposed to predict the behavior of reinforced concrete coupling beams. The model is able to consider the effects of shear and axial forces and bending moment, simultaneously. The proposed model includes a nonlinear shear spring, an axial spring and some nonlinear springs for considering bending deformations. I...

Mechanical behavior of articular cartilage was characterized in unconfined compression to delineate regimes of linear and nonlinear behavior, to investigate the ability of a fibril-reinforced biphasic model to describe measurements, and to test the prediction of biphasic and poroelastic models that tissue dimensions alter tissue stiffness through a specific scaling law for time and frequency. D...

This paper describes triaxial compression tests conducted to determine the effect of fiber inclusion on stiffness and deformation characteristics of sand-gravel mixtures. Tested soil was a mixture of Babolsar sand from the shores of the Caspian Sea and Karaj River gravel. Portland cement was used as the cementing agent and fibers 12mm in length and 0.023mm in diameter at 0%, 0.5% and 1.0% were ...

Buckling of single-walled and multiwalled carbon nanotubes SWNTs and MWNTs, respectively due to axial compressive loads has been studied by molecular mechanics simulations, and results compared with those from the analysis of equivalent continuum structures using Euler buckling theory and the finite element method. It is found that a MWNT of large aspect ratio length/diameter buckles as a colum...