PANDA2, a computer program for the minimum-weight design of elastic perfect and imperfect stiffened cylindrical panels and shells under multiple sets of combined loads, is used to obtain optimum designs of uniformly axially compressed elastic internal T-ring and external T-stringer stiffened cylindrical shells with initial imperfections in the form of the general buckling mode. The optimum desi...

The in-plane compressive behaviour of thin-skin stiffened composite panels with a stress concentrator in the form of an open hole or low velocity impact damage is examined analytically. A fracture mechanics model, developed initially to predict notched compressive strength, was applied to estimate the compression-after-impact strength of a stiffened panel; in the analysis the impact damage is r...

2014 Recent experiments have shown that interdigital transducers can couple strongly to plate modes in piezoelectric composite membranes. In this paper the dispersive properties and the piezoelectric coupling (039403BD/03BD) to these plate modes are presented The various types of modes are identified and related to crystalline symmetry. Results are given for stiffened-shear modes in zinc oxide ...

We present cylindrically symmetric, static solutions of the Einstein field equations around a line singularity such that the energy momentum tensor corresponds to infinitely thin photonic shells. Positivity of the energy density of the thin shell and the line singularity is discussed. It is also shown that thick shells containing mostly radiation are possible by a numerical solution. PACS numbe...

Thin walled cylindrical shells are important components of industrial structures such as liquid storage tanks, silos, etc. Shell buckling is usually a major failure mode of thin walled shells under extreme loads such as earthquakes. Longitudinal and radial stiffeners are generally used in order to increase buckling capacity of thin walled shells. During an earthquake, cylindrical shells may exp...

Cylindrical shells, unstiffened or stiffened with rings and/or stringers are commonly used in offshore structures as main loading-carrying members. Comprehensive theoretical work and experimental studies on the buckling behavior of cylindrical shells have been carried out in the past. The increasing offshore application of stiffened cylindrical shells has raised some new challenges that need to...

In this paper, the buckling behavior of a composite lattice cylindrical shell is studied and effects of rib defects on the distribution of stress field and buckling response of the shell is investigated. A three dimensional finite element buckling analysis of the lattice shell is carried out using ANSYS suit of program. Geometrical data and material properties of the shell are obtained from the...

European aircraft industry demands for reduced development and operating costs, by 20% and 50% in the short and long term, respectively. Contributions to this aim are provided by the completed project POSICOSS and the running follow-up project COCOMAT, both supported by the European Commission. As an important contribution to cost reduction a decrease in structural weight can be reached by expl...

in the present study, vibration of cylindrical laminates with different layers and angles were studied. in order to actuate and polarize in radial direction, a piezoelectric layer was located at outer surface of composite shell. laminates were assumed long enough so that plane strain state analysis in 2d can be used properly. in order to satisfy the boundary conditions, variables in terms of fo...