A Newtonian (vectorial) approach is used to develop the governing differential equations of motion for a three layer sandwich beam in which the uniform distribution of mass and stiffness is dealt with exactly. The model allows for each layer of material to be of unequal thickness and the effects of coupled bending and longitudinal motion are accounted for. This results in an eighth order ordina...

in this article, vibration analysis of an euler-bernoulli beam resting on a pasternak-type foundation is studied. the governing equation is solved by using a spectral finite element model (sfem). the solution involves calculating wave and time responses of the beam. the fast fourier transform function is used for temporal discretization of the governing partial differential equation into a set ...

Focusing on the problem of drilling fluid loss circulation due to fractured granite formation in ultra-deepwater research area, a novel self-degrading loss-circulation material is developed with polymer resin as core material, according principles prevention and reservoir environmental protection. The relevant properties are evaluated by using tests or experiments. pressure-bearing sealing capa...

Nowadays, steel shear walls are used as efficient lateral-load-resistant systems due to their high lateral stiffness and carrying capacity. In this paper, the effect of substituting a shape memory alloy (SMA) material is investigated instead of using conventional steel in the shear wall. A numerical study is conducted using finite element method (FEM) by OpenSees software. For this purpose, at ...

BACKGROUND Gender differences in passive frontal plane knee stiffness may contribute to the increased anterior cruciate ligament injury rate in females. Gender-based stiffness differences have been attributed to anthropometric variations, but little data exist describing this relationship. Furthermore, sex hormone levels appear to influence joint stiffness, but the differential effects of insta...

Mechanical properties of cells and extracellular matrix (ECM) play important roles in many biological processes including stem cell differentiation, tumor formation, and wound healing. Changes in stiffness of cells and ECM are often signs of changes in cell physiology or diseases in tissues. Hence, cell stiffness is an index to evaluate the status of cell cultures. Among the multitude of method...

Results of an analytical and experimental study to characterize the structural response of two compression-loaded variable stiffness composite panels are presented and discussed. These variable stiffness panels are advanced composite structures, in which tows are laid down along precise curvilinear paths within each ply and the fiber orientation angle varies continuously throughout each ply. Th...