A series of experiments have been performed to determine the mechanisms of failure in compressively loaded laminated plates in the presence of stress gradients generated by a circular cutout. Real time holographic interferometry and in-situ photomicrography of the hole surface, along with strain gage measurements are used t o study the progression of failure. The test specimens are multi-layere...

We evaluated the applicability of ply PCR for confirmation of the identification of Streptococcus pneumoniae. lytA PCR, 16S rRNA sequencing, and amplified-fragment length polymorphism were used as reference methods. In contrast to the lytA gene, the ply gene proved to be not specific for S. pneumoniae. The presence of the ply gene in other streptococci, in particular Streptococcus mitis, sugges...

In the present research, the elastic buckling of composite cross-ply elliptical cylindrical shells under axial compression is studied through finite element approach. The formulation is based on shear deformation theory and the serendipity quadrilateral eight-node element is used to study the elastic behavior of elliptical cylindrical shells. The strain-displacement relations are accurately acc...

The present work describes a multiscale methodology which has been developed for modeling of impact damage in the laminated composite structures. The methodology employs the High Fidelity Generalized Method of Cells (HFGMC) micromechanical model for the prediction of the local stress and strain fields, within the representative unit cell of the unidirectional composite material. The Mixed Mode ...

Optimal design of laminated composite stiffened panels of symmetric and balanced layup with different number of T-shape stiffeners is investigated and presented. The stiffened panels are simply supported and subjected to uniform biaxial compressive load. In the optimization for the maximum buckling load without weight penalty, the panel skin and the stiffened laminate stacking sequence, thickne...

The ply number of a drawing is a new criterion of interest for graph drawing. Informally, the ply number of a straight-line drawing of a graph is defined as the maximum number of overlapping disks, where each disk is associated with a vertex and has a radius that is half the length of the longest edge incident to that vertex. This paper reports the results of an extensive experimental study tha...

Angle-ply carbon fibre reinforced polymer (CFRP) crush tubes were tested in drop weight impact experiments. High-fidelity computational modelling of the dynamic response was performed using explicit finite element analysis LS-DYNA. Ply-by-ply and fibre-aligned meshing used for composite lamina wherein intralaminar damage treated with a 3D rate- pressure-dependent continuum mechanics (CDM) model...

This study investigates the influence of load ratio and impact damage on fatigue behaviour high-performance carbon fibre reinforced polymers (CFRP) with areal weights between 30 gsm 360 gsm. For undamaged samples, ultimate tensile compressive strength, as well properties, are evaluated regard to their layer thicknesses. The tests were performed under tension-tension (R=0.1), tension-compression...

There is an increased use of fiber reinforced polymer composites (FRPC) in a wide area of engineering fields for various reasons including, ease of transportation and installation, high strength to weight ratio and favorable durability in different conditions. On the other hand, the use of this material as confining shells has been an interesting matter for retrofit, strengthening and construct...

Although pneumococcal infection is a serious problem worldwide and has a high mortality rate, the molecular mechanisms underlying the lethality caused by pneumococcus remain elusive. Here, we show that BLT2, a G protein-coupled receptor for leukotriene B4 and 12(S)-hydroxyheptadecatrienoic acid (12-HHT), protects mice from lung injury caused by a pneumococcal toxin, pneumolysin (PLY). Intratrac...