The Layerwise Shell Theory is used to model discretely stiffened laminated composite plates and cylindrical shells for stress, vibration, pre-buckling and post-buckling analyses. The layerwise theory reduces a 3-D problem to a 2-D problem by expanding the 3-D displacement field as a function of a surface-wise 2-D displacement field and a 1-D interpolation polynomial through the shell thickness....

Elastic stability of ring and stringer-stiffened cylindrical shells under axial, internal and external pressures is studied using Ritz method. The stiffeners are rings, stringers and their different arrangements at the inner and outer surfaces of the shell. Critical buckling loads are obtained using Ritz method. It has been found that the cylindrical shells with outside rings are more stable th...

Different analytical approaches can be used to model the forced response of the beam-stiffened plates or shells that are commonly found in many practical structures from ships to aircraft. A popular method is to smear the mass and stiffness properties of the beam stiffeners to give an orthotropic plate or shell. This is simpler than modelling discrete stiffeners. This paper considers the exampl...

The cylindrical shell is a widely used structure in engineering practice, and its main form of failure instability due to buckling. As classical problem the field mechanics, stability shells has been studied extensively. However, large difference between theoretically predicted results critical buckling load experimental for subjected uniform axial pressure contributed continuous development th...

The buckling analysis of stiffened cylindrical shells by rings and stringers made of functionally graded materials subjected to axial compression loading is presented. It is assumed that the material properties vary as a power form of the thickness coordinate variable. The fundamental relations, the equilibrium and stability equations are derived using the first order shear deformation theory. ...

Many works can be found in the literature concerning the vibroacoustic modelling of submerged stiffened cylindrical shells, because of high interest in the industrial domain, in particular for aeronautical or naval applications. However, only a few of them take into account non-axisymmetric internal frames, as for instance engine foundations or floor partitions, that can play a role on the vibr...

A belt-conveyor bridge is built inside a ring-stiffened cylindrical shell. The unknown variables are the shell thickness as well as the thickness and the number of flat rings. Optimum solutions are evaluated for different bridge lengths. The design constraints relate to the local shell buckling strength, to the panel ring buckling and to the deflection of the bridge. The cost function includes ...