Thi« report presents a method for determining shear modulus and shear strength of unidirectional flber-relnforced composites. The method Incorporates data from unlaxlal tensile and/or oompresslve tests at fiber orientations of 0, 45, and 90 degrees. The approach presented requires fewer specimens for shear strength determinations than current exlstinc procedures. ^ Distribution of this abstract...

The goal of elastography is to image the shear stiffness of tissue for cancer diagnosis and the focus of this paper is on single frequency elastographic data. Assuming that the measured displacement of the propagating shear wave satisfies the acoustic wave equation, the shear modulus μ can be recovered by solving a first-order partial differential equation in the inverse problem. To capture pos...

The postperovskite transition in MgSiO(3) at conditions similar to those expected at the D'' discontinuity of Earth's lower mantle offers a paradigm for interpreting the properties of this region. Despite consistent experimental and theoretical predictions of this phase transformation, the complexity of the D'' region raises questions about its geophysical significance. Here we report the therm...

This study reports the application of a novel method for quantitatively determining differences in the mechanical properties of healthy and torn rotator cuff tissues. In order to overcome problems of stress risers at the grip-tendon interface that can obscure mechanical measurements of small tendons, we conducted our investigation using dynamic shear analysis. Rotator cuff tendon specimens were...

Reliable clot diagnostic systems are needed for directing treatment in a broad spectrum of cardiovascular diseases and coagulopathy. Here, we report on non-contact measurement of elastic modulus for dynamic and quantitative assessment of whole blood coagulation using acoustic radiation force orthogonal excitation optical coherence elastography (ARFOE-OCE). In this system, acoustic radiation for...

New velocity data in addition to literature data derived from sonic log, seismic, and laboratory measurements are analyzed for elastic silicate rocks. These data demonstrate simple systematic relationships between compressional and shear wave velocities. For water-saturated elastic silicate rocks, shear wave velocity is approximately linearly related to compressional wave velocity and the compr...

The response of a neo-Hookean fiber composite undergoing finite out-of-plane shear deformation is examined. To this end an explicit close form solution for the out-of-plane shear response of a cylindrical composite element is introduced. We find that the overall response of the cylindrical composite element can be characterized by a fictitious homogeneous neo-Hookean material. Accordingly, this...

[1] We calculated the elasticity of (Mg,Fe)SiO3-perovskite, using the plane-wave pseudopotential method for a pressure range that encompasses the earth’s lower mantle. Adding 25 mol% FeSiO3 to the Mg endmember decreases the shear modulus by 6% at zero pressure and by 8% at core mantle boundary pressures. The bulk modulus is less affected by iron, increasing by 2% at zero pressure and by 1% at t...

In this paper, a novel method to estimate the shear wave speed is proposed. This method is a modified version of the lateral Time to Peak (TTP) method that estimates the induced shear wave speed. Lateral TTP algorithm finds the instance at which the maximum displacement is detected at each lateral location under examination at a certain depth. In the proposed algorithm each temporal displacemen...

Due to its complicated architecture, the mechanical properties of articular cartilage (AC) are highly nonlinear and exhibit clear spatial variations that may be critical to proper function. In a previous study, we characterized the depth-dependent, steady-state shear properties of neonatal bovine tissue using a Harrick Scientific tissue deformation imaging stage (TDIS) mounted on a confocal mic...