In the case of study on the seismic behavior of tanks, one of the most important subjects is selection of convective and impulsive frequencies for storage tanks. These two frequencies are defined by Housner. The major utility of these frequencies is for Rayleigh damping which is a must for time history analysis. API 650, EUROCODE 8 have suggested some analytical solutions for finding convective...

Dynamic behavior of ground supported cylindrical storage tanks (CST) is of crucial importance because of its applications in industrial complexes. Seismic behavior of tanks is greatly affected by the height to diameter ratio, fluid height and fluid type. Five CSTs with different height to diameter ratios, three CSTs with the same height and diameters but various fluid heights and one CST with t...

Based on the Frobenius series method, stresses analysis of the functionally graded rotating thick cylindrical pressure vessels (FGRTCPV) are examined. The vessel is considered in both plane stress and plane strain conditions. All of the cylindrical shell properties except the Poisson ratio are considered exponential function along the radial direction. The governing Navier equation for this pro...

7 This paper describes the development of an efficient numerical model, namely scaled bound8 ary finite-element method (SBFEM) for linear waves interaction with cylindrical structures 9 of arbitrary shapes. The two-dimensional Helmholtz equation is firstly weakened in the cir10 cumferential direction, so that the governing partial differential equation is transformed to 11 an ordinary matrix di...

Cylindrical shells are used in a variety of applications. In some of these applications it is necessary to limit the vibrations of lightly-damped shells by applying a damping treatment that does not significantly increase the weight. This paper explores the use of partial coating of a cylindrical shell with a constrained viscoelastic layer for obtaining optimal damping. The placement of damping...

Buckling analyses of heavily corrugated cylindrical shells based on detailed full finite element models are usually computationally expensive. To address this issue, we have proposed an efficient computational method of predicting the onset of buckling for corrugated cylindrical shells which builds on the Bloch wave method for infinitely periodic structures. We modified the traditional Bloch wa...

In this paper the individual and combined effects of random boundary and geometric imperfections on the limit loads of isotropic, thin-walled, cylindrical shells under axial compression are presented. Second moment characteristics of these imperfections are estimated by data of available measurements of imperfections, a simulation procedure based on the Karhunen-Loéve expansion is applied for g...

Application of impact energy absorption systems in different industries is of special significance. Thin-walled tubes, due to their lightness, high energy absorption capacity, long crushing length and the high ratio of energy absorption to weight, have found ever-increasing application as one of the most effective energy absorption systems. In this research, through  carrying out experimental t...

This 3D finite element study assessed the stress distribution in mandibular overdenture supported by the 3i Locator system attached to two cylindrical or conical implants placed at the canine region. A 100 N vertical load was applied over the right first molar of the two overdenture models. The von Mises stresses were concentrated at the cervical and middle implant thirds. Cylindrical implants ...

Design and application of super elements in efficient prediction of the structural behaviour in a short time has been one of the research interests in the last decade. A new 16-node cylindrical super element is presented in this paper and implemented to modal analysis of hollow cylinders subjected to various boundary conditions. Comparison of the findings with conventional finite element reveal...