Stress Analysis of Orthotropic Noncircular Cylindrical Shells of Variable Thickness in a Refined Formulation

An approach is developed to solve stress–strain problems in a refined formulation for orthotropic cylindrical shells of variable thickness and noncircular cross section. It is shown, as an example, how the distributions of deflections and stresses depend on changes in the shell thickness at constant weight     

Stress-Strain Analysis of Orthotropic Closed and Open Noncircular Cylindrical Shells

The paper proposes an approach to the stress-strain analysis of orthotropic open and closed cylindrical shells of variable thickness and noncircular cross section under various loading and boundary conditions. As an example, the circumferential distribution of deflection and tangential force in shells with elliptic cross section is analyzed for some cases of orthotropy __________ Translated from Prikladnaya Mekhanika, Vol. 41, No. 7, pp. 83–92, July 2005.     

Influence of Variable Thickness on Displacements and Stresses in Nonthin Cylindrical Orthotropic Shells with Elliptic Cross-Section

The influence of varying thickness at constant mass on the stress–strain state of orthotropic cylindrical shells with elliptic cross-section is analyzed by solving two-dimensional boundary-value problems     

Analysis of Stresses and Displacements in Orthotropic Noncircular Cylindrical Shells Under Centrifugal Loads

This paper addresses the class of stress–strain problems for thin orthotropic cylindrical shells of arbitrary cross section under centrifugal loads. Separating out the variables for a simply supported shell yields a system of ordinary differential equations for which the boundary-value problem is solved by a stable numerical method. Study is made of the distribution of displacements in shells of elliptical cross section versus the ratio of ellipse exes and the eccentricity of the axis of revolution relative to the geometrical axis of symmetry     

Stability of Axially Compressed Noncircular Cylindrical Shells Consisting of Panels of Constant Curvature

The stability problem is solved for an axially compressed cylindrical shell. Its cross section is formed by circular arcs of radius r with ends supported on a closed circle of radius R. The solution is based on the Flügge equations of the classic theory of deep cylindrical shells. It is shown that the critical axial load for shells of medium length and appropriately chosen cross-sectional profile can be increased by a factor of R/r approximately, compared with the circular shell. The shells length affects considerably the efficiency of noncircular shells of this type. This design model allows us to find out how the local properties of the shell and its stiffness are related     

The Effect of a Geometrical Parameter on the Deformation of a Hinged Flexible Noncircular Cylindrical Shell

The exact analytical solution of a nonlinear boundary-value problem is used to study the effect of a generalized geometric parameter, which characterizes thickness and curvature, on the subcritical and postcritical deformation of a hinged infinite noncircular cylindrical shell. The load on the shell is nonuniformly distributed over its cross section. The deflection of the shell is plotted for various values of the geometric parameter     

Analysis of the Influence of a Geometrical Parameter on the Deformation of a Rigidly Fixed, Flexible, Noncircular Cylindrical Shell

The exact analytical solution of the deformation problem for a flexible long noncircular cylindrical shell is used to analyze how a geometrical parameter characterizing the wall thickness and curvature of the shell affects its behavior when its longitudinal edges are rigidly clamped. Plots of the deflection–load relationship are presented for various values of the geometric parameter     

层合圆柱壳的振动与横向应力

应用分层壳理论并在壳厚方向彩二次插值函数推导出正交层合圆醉壳的动力学方程,并得出了简支层合圆柱壳自由振动方程的解,所给出的振动频率与三维分析的结果吻合良好,计算了前四阶模态对应的壳中应力,与第三、四阶模态对应的横向正应力与面内应力的比值远高于第一、二阶模态的应力比,计算结果说明,很高的横向正应力是高频动力响应中导致分层壳脱层破坏的一个主要因素。     

轴向冲击载荷下圆柱壳的弹塑性屈曲分析

研究时变轴向冲击载荷作用下的圆柱壳弹塑性动力屈曲问题。本构关系采用增量理论 ,借助增量数值计算方法对Karman Donnell运动方程进行求解。计算表明 :基于B R准则的屈曲判断方法和采用Southwell方法可以获得一致的临界屈曲载荷 ;分别讨论了应力波对屈曲的影响以及材料参数、几何参数、载荷峰值与持续时间和动力屈曲的关系。     

厚壁圆柱壳的弹性静力分析

本文研究了考虑横向剪切影响的弹性厚壁圆柱壳的静力问题。利用变分原理得到平衡微分方程组和相应的边界条件。将平衡方程组归并成一个高阶微分方程,用数值法求出它的特征根,得到问题的解。     

Nonaxisymmetric Vibrations of Discretely Reinforced Inhomogeneous Multilayer Cylindrical Shells under Nonstationary Loads

The equations of nonaxisymmetric vibrations of discretely reinforced multilayer cylindrical shells are analyzed. A refined Timoshenko model of shells and beams is used to analyze elements of an elastic structure. The vibration equations for an inhomogeneous elastic system are derived using the Reissner variational principle. The numerical solver of the dynamic equations is based on the integro-interpolation method used to construct finite-difference schemes for equations with discontinuous coefficients. The dynamic behavior of a five-layer cylindrical shell under distributed nonstationary loading is analyzed     

圆柱壳稳定性问题的研究进展

圆柱壳是工程实际中广泛应用的结构,其主要破坏形式是屈曲失稳．作为力学领域的经典问题,圆柱壳稳定性问题的研究非常之多．其中,受均匀轴向压力的圆柱壳由于临界屈曲载荷的理论预测值与早期试验结果之间的巨大差异,更是推动了壳体稳定性理论的不断发展．本文简要回顾了壳体稳定性理论的发展和分类,并对轴压圆柱壳体试验结果分散且远低于理论预测值的原因及含缺陷圆柱壳体的稳定性研究方法进行了总结,然后综述了地下空间顶管、储油罐、加筋圆柱壳及脱层圆柱壳等实际工程中广泛应用的圆柱壳结构稳定性研究的现状和趋势,最后展望了将来对工程应用中圆柱壳结构的稳定性研究的难点和方向．     

Stability of Cylindrical Shells with High Ribs

The paper presents a technique for stability analysis of cylindrical shells reinforced with longitudinal elements in the form of a plate or a flanged plate. The effect of the widths of the plate and flange on the critical stress and buckling modes is analyzed     

Circumferential Traveling Waves in Filled Cylindrical Shells

Consideration is given to deformation in the form of traveling circumferential waves in circular cylindrical shells with a liquid. The effect of the liquid on the phase velocity in the carrier shell is studied depending on the waveformation parameters and initial conditions     

Nonlinear Theory of Dynamic Stability for Laminated Composite Cylindrical Shells

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正交各向异性功能梯度圆柱壳的自由振动

利用从弹性力学的三维基本方程导得的状态方程，结合层合近似模型，求得了柱型正交各向异性功能梯度圆柱壳的自由振动频率，给出了数值算例，并与前人结果作了比较，文末讨论了相关参数的影响。     

Natural Vibrations of Ribbed Cylindrical Shells with Low Shear Stiffness

A technique is proposed to determine the natural frequencies of rib-reinforced cylindrical shells with low shear stiffness. The equations of motion based on the Timoshenko model are used. The influence of the transverse shear moduli of the shell and ribs on the minimum natural frequencies and corresponding modes is studied by way of numerical examples. It is shown that the effect of the discrete ribs is different from that predicted by the classical theory of ribbed shells__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 4, pp. 66–74, April 2005.     

Edge Resonance in Structurally Orthotropic Cylindrical Shells

Possibilities for edge resonances to occur in structurally orthotropic cylindrical shells through which harmonic waves propagate are studied. It is shown that such resonances may be generated by axisymmetric longitudinal flexural waves propagating in a rigidly clamped semi-infinite shell __________ Translated from Prikladnaya Mekhanika, Vol. 41, No. 7, pp. 93–101, July 2005.     

The Stress State of Multilayer Flexible Cylindrical Shells of Variable Stiffness

The deformation of flexible multilayer circular cylindrical shells of variable stiffness is studied under a refined theory that accounts for the inhomogeneity of transverse shear strains. The effect of variation in the thickness at constant weight on the stress–strain state of a shell is analyzed     

轴向应力波作用下圆柱壳弹性轴对称动力失稳有限元特征值分析

本文运用有限元特征值分析方法对应力波作用下圆柱壳弹性轴对称动力失稳问题进行了研究。基于应力波理论和相邻平衡准则导出了圆柱壳轴对称动力失稳时的有限元特征方程,在此方程中考虑了应力波效应及横向惯性效应,把圆柱壳弹性动力失稳问题归结为特征值问题。通过引入圆柱壳动力失稳时的波前约束条件实现了此类问题的有限元特征值解法。计算结果揭示了圆柱壳弹性轴对称动力屈曲变形发展的机理,以及轴向应力波和屈曲变形的相互作用规律。