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In this paper, buckling and energy absorption behavior of stainless steel semi-sphere, cylindrical and conical shells under axial loading are studied. Every shell with the same mass and different shapes with and without groove is designed. In this paper the effect of shape, thickness, height, groove of shells and distance between grooves, on buckling and energy absorption were investigated. In experimental test, Samples had same mass and thickness and also grooves had same depth and distance. Experimental tests were performed by a servo-hydraulic INSTRON 8802 machine. Numerical analysis is carried out by ABAQUS software and is validated with experimental results.

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A numerical and experimental study of the collapse and energy absorption behavior of thin-walled end capped conical shells under dynamic loading is presented in this paper. Among the structural components, the truncated conical shells whose energy absorption characteristics are better than others are used. In order to carry out the designed tests, a drop hammer machine has been used. Also in numerical part, Abaqus software capabilities have been applied. In this article, the effect of the velocity and mass of the hammer on the collapse behavior of these samples has been investigated. Moreover, by placing the cone reversely, the force effect on the collapse behavior evaluated and analyzed. Also, the multiple sets of cones as energy absorbing system are analyzed numerically. For the samples, mode of collapse of diamond with quadrilateral pattern was obtained and a very good agreement with experimental results was recorded. The results shows that the change of wall thickness has the most influence on the collapse behavior of these shells. So that with a 20% reduction of shell thickness, maximum force had 34.5% and the average force collapse 39.3% reduction.

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Conical shells are widely used in various engineering applications such as mechanical, civil and aerospace engineering. In the present paper, based on the first order shear deformation theory (FSDT) of shells, the nonlinear vibration behavior of truncated conical shells with different boundary conditions is investigated using a numerical approach. To this end, the governing equations of motion and corresponding boundary conditions are derived by the use of Hamilton's principle. After catching the dimensionless form of equations, the generalized differential quadrature (GDQ) method is employed to obtain a discretized set of nonlinear governing equations. Thereafter, a Galerkin-based scheme is applied to achieve a time-varying set of ordinary differential equations and a method called periodic grid discretization is used to discretize the equations on the time domain. The pseudo arc-length continuation method is finally applied to obtain the frequency-amplitude response of conical shells. Selected numerical results are presented to examine the effects of different parameters such as thickness-to-radius ratio, small-to-large edge radius ratio, semi-vertex angle of cone, circumferential wave number and boundary conditions. It is concluded that the changes of the vibrational mode shapes and circumferential wave number have significant effects on the nonlinear vibration characteristics and hardening effects.