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41.
含分层损伤复合材料层合板的压缩强度研究 总被引:5,自引:0,他引:5
给出了基于一阶剪切变形理论的含分层损伤层合板有限元分析模型,将含分层损伤层合板在压缩载荷作用下的强度破坏分析和屈曲破坏分析统一起来,先区分其破坏形式,然后再进行具体破坏分析.在屈曲特性分析中考虑了铺层强度破坏引起的刚度折减的影响.数值结果表明, 该文给出的方法和结论对含分层损伤复合材料层合板的设计更具参考价值. 相似文献
42.
Sofiyev Abdullah Ay Zeki 《Acta Mechanica Solida Sinica》2003,16(1):81-87
The subject of this investigation is to study the buckling of orthotropic cylindricalthin shells under torsion,which is a power function of time.The dynamic stability and compati-bility equations are obtained first.These equations are subsequently reduced to a time dependentdifferential equation with variable coefficient by using Galerkin's method.Finally,the critical dy-namic and static loading,the corresponding wave numbers,the dynamic factors,critical time andcritical impulse are found analytically by applying the Ritz type variational method.Using thoseresults,the effects of the variations of the power of time in the torsion load expression,of theloading parameter,the ratio of the Young's moduli and the ratio of the radius to thickness onthe critical parameters are studied numerically.It is observed that these factors have appreciableeffects on the critical parameters of the problem in the heading. 相似文献
43.
复合结构剪切板的屈曲与后屈曲研究 总被引:11,自引:0,他引:11
基于Reissner剪切板理论,本文将现有理论模型推进了一步,导出了控制复合材料和构造矩形板平衡的广义Karman大挠度方程。此外,运用摄动技术,构造了一个单向压缩简支剪切矩形板的后屈曲渐近解,适用于面板和夹心材料都具正交各向异性的夹层板以及计及横向剪切变形对称铺设的层合板。文中给出了典型算例,并将当前结果与其它理论或数值解作了比较,显示出相当好的一致性。 相似文献
44.
45.
We present the next‐to‐next‐to‐leading order post‐Newtonian (PN) spin(1)‐spin(2) Hamiltonian for two self‐gravitating spinning compact objects. If both objects are rapidly rotating, then the corresponding interaction is comparable in strength to a 4PN effect. The Hamiltonian is checked via the global Poincaré algebra with the center‐of‐mass vector uniquely determined by an ansatz. 相似文献
46.
An analytical method is presented to study the non-linear buckling characteristic of rectangular local delamination near the surface of fiber-reinforced piezoelectric lamination shells under coupled mechanical and electric loads. The stacking sequence of fiber reinforced lamination shells with piezoelectric layers is considered as symmetry, but the stacking sequence of rectangular local delamination sub-shells is arbitrary. Based on the nonlinear displacement mode of delaminated sub-shells, the effects of electric fields, the geometrical, physical parameters and stacking sequences of piezoelectric laminated shells on the non-linear local buckling for rectangular delamination near the surface of piezoelectric laminated base-shells are solved. 相似文献
47.
Notionsa. b, h Plate dimensionsL', [-. [1- mid-plane displacement componentsu- v- Ic dboensionless mid-plane displacement componentsVy., ac'~ slOPeS in xo and gi plane, ropectivelyJll, N number of terms in Cheby-shev series in x and y directions, respectivelyCCCC all edges clampedSSSS all edges simply supportedCCCS three edges (x = fi and y = 1) clamped and one (y = --1) simply supportedCCSS two edges (x = 11) clamped and two (y = fi) simply supportedCSSS one edge (x = --1) clamped … 相似文献
48.
49.
FLUTTER INSTABILITY OF SUPPORTED PIPES CONVEYING FLUID SUBJECTED TO DISTRIBUTED FOLLOWER FORCES 总被引:1,自引:0,他引:1
Lin Wang 《Acta Mechanica Solida Sinica》2012,25(1):46-52
In the past decades,it has been reported that divergence is the expected form of instability for fluid-conveying pipes with both ends supported.In this paper,the form of instability of supported pipes ... 相似文献
50.
We consider the overdetermined eigenvalue problem on a sufficiently regular connected open domain Ω on the 2-sphere
:
where α ≠ 0. We show that if α = 2 and Ω is simply connected then the problem admits a (nonzero) solution if and only if Ω is a geodesic disk. We furthermore extend to domains on
the isoperimetric inequality of Payne–Weinberger for the first buckling eigenvalue of compact planar domains. As a corollary we prove that Ω is a geodesic disk if the above overdetermined eigenvalue problem admits a (nonzero) solution with ∂u/∂ν = 0 on ∂Ω and α = λ2 the second eigenvalue of the Laplacian with Dirichlet boundary condition. This extends a result proved in the case of the Euclidean plane by C. Berenstein. 相似文献