At present time, the spectral dynamic stiffness method is being actively developed as an alternative to finite element for vibration and stability problems of composite structures from beams, rods, plates shells. This approach, based on exact solutions governing differential equations, makes it possible more effectively study problem in medium high frequency ranges, gives analytical expressions...

Ultrasonic S0 waves (fundamental symmetric Lamb modes) are being considered in several laboratories for the nondestructive characterization of the texture (preferred grain orientation) and formability of metal sheets and plates. In a typical experimental setup, the velocities of the S0 waves are measured as a function of wave propagation angle with respect to the rolling direction of the plate....

Fracture analysis of orthotropic cracked media is investigated by applying the recently developed extended isogeometric analysis (XIGA) (Ghorashi et al., 2012) using the T-spline basis functions. The signed distance function and orthotropic crack tip enrichment functions are adopted for extrinsically enriching the conventional isogeometric analysis approximation for representation of strong dis...

There are different dynamic or static test methodologies for evaluating the shear and torsional moduli of wood. A preferred method is nondestructive, accurate, and standard. However, dynamic methods using conventional devices previously suggested for determining the orthotropic shear moduli of wood are neither accurate nor standard. Thus, a reliable method for evaluating the torsional modulus o...

A thin, solid, circular wood disk, cut from the transverse plane of a tree stem, can be modeled as a cylindrically orthotropic elastic material. It is known that a stress singularity can occur at the center of a cylindrically orthotropic disk subjected to uniform pressure. If a solid cylindrically orthotropic disk is subjected to sinusoidal pressure distributions, then other stress singularitie...

A method is presented to find orthotropic elastic symmetries and constants directly from the elastic coefficients in the overall stiffness matrix of trabecular bone test specimens. Contrary to earlier developed techniques, this method does not require pure orthotropic behavior or additional fabric measurements. The method uses high-resolution computer reconstructions of trabecular bone specimen...

In this article, classical plate theory (CPT) is reformulated using the nonlocal differential constitutive relations of Eringen to develop an equivalent continuum model for orthotropic triangular nanoplates. The equations of motion are derived and the Galerkin’s approach in conjunction with the area coordinates is used as a basis for the solution. Nonlocal theories are employed to bring out the...

The orthotropic steel deck is sensitive to fatigue, and a number of cracks have been found in existing bridges. Based on the long-span Guangzhou Mingzhu Bay arched bridge, this paper focus cracking process, fatigue mechanism, performance evaluation an bridge under traffic load. A finite element model three-U-rib three-span was first established investigate stress state most unfavorable wheel lo...

A new model for fatigue damage evolution of polymer matrix composites is presented. The model is based on a combination of an orthotropic damage model and an isotropic fatigue evolution model. The orthotropic damage model is used to predict the orthotropic damage evolution within a single cycle. The isotropic fatigue model is used to predict the magnitude of fatigue damage accumulated as a func...

Orthotropic steel decks (OSD's) are susceptible to fatigue failure due cyclic loading. Often cracks found in the joint between deck plate and trough. Due welding process, residual stresses present around joint. In this paper, effect of on crack propagation rate has been evaluated. First, a FE model made predict validate stress field OSD welding. The validation is comparing measured data at surf...