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1.
A compressive postbuckling analysis is presented for a laminated cylindrical shell with piezoelectric actuators subjected to the combined action of mechanical, electric and thermal loads. The temperature field considered is assumed to be a uniform distribution over the shell surface and through the shell thickness, and the electric field is assumed to be the transverse component EZ only. The material properties are assumed to be independent of the temperature and the electric field. The governing equations are based on the classical shell theory with von Kármán–Donnell-type kinematic nonlinearity. The nonlinear prebuckling deformations and initial geometric imperfections of the shell are both taken into account. A boundary layer theory of shell buckling, which includes the effects of nonlinear prebuckling deformations, large deflections in the postbuckling range, and initial geometric imperfections of the shell, is extended to the case of hybrid laminated cylindrical shells. A singular perturbation technique is employed to determine the buckling loads and postbuckling equilibrium paths. The numerical illustrations concern the compressive postbuckling behavior of perfect and imperfect, cross-ply laminated cylindrical thin shells with fully covered or embedded piezoelectric actuators under different sets of thermal and electric loading conditions. The effects played by temperature rise, applied voltage, shell geometric parameter, stacking sequence, as well as initial geometric imperfections are studied.  相似文献   

2.
I.IntroductionStiffenedandunstiffenedcircularcylindricalshellsfoundwideusesasprimarystructuralcomponentsinunderwatervehicles,offshoreplatformsandotherstructuralconfigurations.Theinitialinvestigationofthebucklingofstiffenedandunstiffenedcircularcylindrical…  相似文献   

3.
Buckling and postbuckling behaviors of perfect and imperfect,stringer andorthotropically stiffened cylindrical shells have been studied under axial compression.Based on the boundary layer theory for the buckling of thin elastic shells suggested in ref.[1],a theoretical analysis is presented.The effects of material properties of stiffeners andskin,which are made of different materials,on the buckling load and postbuckling behaviorof stiffened cylindrical shells have also been discussed.  相似文献   

4.
IntroductionInrecentyears,fiber_reinforcedcompositelaminatedpanelshavebeenwidelyusedintheaerospace,marine ,automobileandotherengineeringindustries .Theproblemofbucklingandpostbucklingofcylindricalpanelsunderaxialcompressionortorsionhasbeenextensivelystudied .Incontrast,theliteratureoncylindricalpanelsunderpressureloadingisrelativelyspares.Thesestudiesincludealinearbucklinganalysis (Singeretal.[1]) ,anonlinearbucklinganalysi(YamadaandCroll[2 ]) ,anelastoplasticbucklinganalysisusingreducedstif…  相似文献   

5.
IntroductionInrecentyears,fiber_reinforcedcompositelaminatedshellstructuresarewidelyusedintheaerospace ,marineindustry ,automobileindustryandotherengineeringapplications.Duringtheoperationallife ,thevarianceoftemperatureandmoisturereducestheelasticmoduli…  相似文献   

6.
IntroductionCompositelaminatedcylindricalpanelhasbeenusedextensivelyasastructuralconfiguration,mainlyintheaerospaceindustry .Oneoftherecentadvancesinmaterialandstructuralengineeringisinthefieldofsmartstructureswhichincorporatesadaptivematerials.Bytakingadvantageofthedirectandconversepiezoelectriceffects,piezoelectriccompositestructurescancombinethetraditionalperformanceadvantagesofcompositelaminatesalongwiththeinherentcapabilityofpiezoelectricmaterialstoadapttotheircurrentenvironment.Therefore…  相似文献   

7.
将Koiter理论和奇异摄动理论中的边界层法相结合处理加筋圆柱壳无因次化非线性边界层型Karman-Donnel方程由分支点和边界层导致的双重奇异性,提出外压加筋圆柱壳总体屈曲Koiter—边界层奇异摄动法。从摄动意义上分析边界条件,前屈曲非线性和初始几何缺陷对外压加筋圆柱壳屈曲载荷的影响。算例表明,本方法具有良好的计算效率和计算精度,与数值解相比更能揭示内在影响规律。  相似文献   

8.
A solution is obtained to describe the stability and initial postbuckling behavior of cylindrical shells made of composites with one plane of symmetry. The solution is based on the Donnell-Mushtari-Vlasov nonlinear theory of anisotropic shells and Koiter’s theory of buckling and postbuckling behavior. Calculated results are presented for boron plastic shells with reinforcement of different types under external pressure. It is shown that the conventional model of a composite as an orthotropic material is erroneous for many types of reinforcement __________ Translated from Prikladnaya Mekhanika, Vol. 43, No. 3, pp. 86–103, March 2007.  相似文献   

9.
This paper presents a step-by-step approximating method to obtain the analyticalsolutions of the differential equations for the self-similar problems of viscous fluid flow(1.1-1.4).Prosnak(1969)obtained solutions of these equations by using a small paremetermethod,but he reduced the governing equations to the linear differential equations withconstant coefficients.  相似文献   

10.
The efficient compound strip method is used to analyse the buckling of ring-stiffened cylindrical shells under hydrostatic pressure. The eccentricity of stiffeners is taken into account. Numerical examples are given to illustrate the efficiency and accuracy of this method.  相似文献   

11.
Based on the governing equation of vibration of a kind of cylindrical shells written in a matrix differential equation of the first order,a new matrix method is pre- sented for steady-state vibration analysis of a noncircular cylindrical shell simply sup- ported at two ends and circumferentially stiffened by rings under harmonic pressure.Its difference from the existing works by Yamada and Irie is that the matrix differential equation is solved by using the extended homogeneous capacity precision integration ap- proach other than the Runge-Kutta-Gill integration method.The transfer matrix can easily be determined by a high precision integration scheme.In addition,besides the normal interacting forces,which were commonly adopted by researchers earlier,the tan- gential interacting forces between the cylindrical shell and the rings are considered at the same time by means of the Dirac-δfunction.The effects of the exciting frequencies on displacements and stresses responses have been investigated.Numerical results show that the proposed method is more efficient than the aforementioned method.  相似文献   

12.
ELASTIC PULSE BUCKLING OF CYLINDRICAL SHELLS UNDER RADIAL IMPULSIVE LOADING   总被引:3,自引:0,他引:3  
ELASTICPULSEBUCKLINGOFCYLINDRICALSHELLSUNDERRADIALIMPULSIVELOADINGHuangChengyi(黄承义)LiuTuguang(刘土光)ZhengJijia(郑际嘉)(Departmento...  相似文献   

13.
本文提出了一种计算环加肋圆柱壳稳定性的新方法─—复合有限条法。该方法能够在一个复合有限条元中计入若干个横向加肋的影响,井能考虑肋骨的偏心,是一种子结构方法。算例表明,复合有限条法具有很高的求解精度和效率,是一种分析加肋柱壳结构的较理想方法。该方法不仅能够计算环加肋圆柱壳的总体失稳临界载荷,而且可计算其局部失稳临界载荷。  相似文献   

14.
A solution is obtained that describes the postbuckling behavior of cylindrical shells in the case of axisymmetric buckling. The basis for this solution is Koiter’s asymptotic method and the nonlinear equations of the third-order Timoshenko theory of shells. It is shown that the bifurcation point in this case is a symmetrically unstable one. The effect of the initial axisymmetric deflections on the buckling loads is weaker when buckling is axisymmetric. The results obtained by Koiter’s special theory evidence this __________ Translated from Prikladnaya Mekhanika, Vol. 42, No. 4, pp. 108–118, April 2006.  相似文献   

15.
针对有内压或外压的弹性圆柱壳在轴向冲击载荷耦合作用下的动态屈曲问题,构造哈密顿体系,在辛空间中将临界载荷和动态屈曲模态归结为辛本征值和本征解问题,从而形成一种辛方法。该方法直接得到非轴对称的屈曲模态。数值结果给出了圆柱壳问题的临界载荷和屈曲模态以及一些规律。  相似文献   

16.
The paper presents an analytical solution describing the stability and postbuckling behavior of a cylindrical shell made of an anisotropic material with one plane of symmetry and subjected to torques at the ends. The solution is found using Koiter's buckling theory and the Donnell-Mushtari-Vlasov theory of anisotropic shells. The force and deflection functions are approximated by trigonometric series that satisfy hinged boundary conditions. The system of algebraic equations to which the problem is reduced at the main stage of solution is analyzed. Specific results on stability and sensitivity to imperfections of boron-plastic shells consisting of layers with different reinforcement directions are obtained __________ Translated from Prikladnaya Mekhanika, Vol. 44, No. 1, pp. 48–73, January 2008.  相似文献   

17.
The buckling problem for longitudinally corrugated cylindrical shells under external pressure is solved. The solution makes practically exact allowance for the geometry and buckling modes of the shell. The inaccuracy of the results is due to the assumption that the subcritical state is momentless. Shells consisting of cylindrical panels of smaller radius and noncircular shells with sinusoidal corrugations are analyzed for stability. The practical applicability of such shells is demonstrated __________ Translated from Prikladnaya Mekhanika, Vol. 43, No. 11, pp. 66–79, October 2007.  相似文献   

18.
A study is made of the stability of cylindrical shells of oval cross section loaded by a shear force combined with torsional and bending moments. The variational method of finite elements in displacements is used. The subcritical stress-strain state of the shells is considered momental and nonlinear. The effects of the nonlinearity of shell deformation and shell ovalization on the critical load and buckling mode are determined. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 1, pp. 134–138, January–February, 2008.  相似文献   

19.
The stability problem of a cylindrical shell of oval cross section loaded by a bending moment and internal pressure is studied. The variational displacement finite-element method is used. For the prebuckling stress-strain state, the bending and nonlinearity are taken into account. The effects of the nonlinear nature of the deformation and the cross-sectional ovality of the shells on the critical loads and buckling modes are determined. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 3, pp. 119–125, May–June, 2006.  相似文献   

20.
分区样条等参元方法分析加肋轴对称组合壳   总被引:8,自引:0,他引:8  
本文提出分区样条等参元方法分析加肋轴对称组合壳在静水外压作用下的应力及稳定性。该方法根据母线几何形状、壳板厚度变化及边界约束状况将加肋轴对称组合壳划分为若干个区域,在不同区域采用不同步长的样条等参元进行分析,因而便于对复杂的组合壳进行分析,并可大大减少计算所需自由度数,减少计算工作量,同时计算精度很高,并且易于进行边界约束处理。应用该方法对加肋锥-柱、加肋锥-环-柱组合壳进行了计算,其结果与其它方法计算值及实验值吻合良好。  相似文献   

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