Free vibration of laminated composite shells with cutouts are presented by a nine noded curved C0 finite element (FE) formulation developed by authors based on higher order shear deformation theory (HSDT) using Sander's approximations. The proposed model satisfies parabolic distribution of transverse shear strains through the shell thickness and zero transverse shear stress conditions at shell ...

Mechanical property and impact resistance mechanism of bionic layered composite was investigated. Due to light weight and high strength property, white clam shell was chosen as bionic model for design of bionic layered composite. The intercoupling model between hard layer and soft layer was identical to the layered microstructure and hardness tendency of the white clam shell, which connected th...

The design of stiffened, composite wing panels must satisfy a range of requirements related to performance, economy and safety. In particular, the design must be damage tolerant to satisfy a number of different performance requirements for various states of damage. To obtain an optimum configuration that satisfies these requirements simultaneously, optimization code PANOPT was extended with a m...

Thermoplastic composites offer many opportunities for aeronautics. Among them is the possibility of overmolding composite parts to obtain finished “netshape” in medium series. This paper presents complexity manufacturing method and defects that may occur some grid-stiffened overmolded using aeronautic thermoplastics. The results impact tests up 15 J carried out at various locations plates grid ...

The paper describes a program currently underway at Composite Technology Development, Inc. to dramatically improve the design and capabilities of lightweight linerless composite tanks. The program integrates material development and characterization, micromechanics-based analyses of composite materials and structural design and fabrication of prototype tanks. This integrated systematic approach...

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...

Shear walls are used in most of the tall buildings for carrying the lateral load. When openings for doors or windows are necessary to be existed in the shear walls, a special type of the shear walls is used called "coupled shear walls" which in some cases is stiffened by specific beams and so, called "stiffened coupled shear walls". In this paper, a mathematical method for geometrically nonline...

This study provides an approach to predict the springback phenomenon during post-solidification cooling in a functionally graded hybrid composite cylindrical shell with a transverse isotropic structure. Here, the material properties are given with a general parabolic power-law function. During the theoretical analysis, an appropriate transformation is introduced in the equilibrium equation, whi...