共查询到20条相似文献,搜索用时 39 毫秒
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本文利用变角度复合材料的纤维方向角可沿平面位置任意连续变化的特点,提出在孔附近采用与孔同心的椭圆曲线作为纤维铺设路径的层合板铺层方案,以改善含椭圆孔的层合板的孔边应力集中,进而提高层合板的抗屈曲性能.主要研究内容有:利用ABAQUS软件分析本文提出的孔边特殊铺层方式下变角度复合材料层合板的面内应力分布及屈曲性能,通过与传统直线铺层方式以及线性变角度铺层方式进行比较,说明了本文提出的新铺层方式的优越性,并详细分析了椭圆孔的离心率、开孔尺寸及开孔方位对层合板的屈曲临界荷载的影响.研究结果可为含椭圆孔的变角度复合材料层合板的结构设计和优化提供一定的参考. 相似文献
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本文通过计算机仿真,观察和研究了铲支艰称正交铺设层合板的周期运动、混沌运动以及它们各自的吸引子,其系统动力响应的形式,用时间历程图、相位状态图和Poincare映射图来表示。结果表明,在受迫振动的对称正交铺设层合存在着混沌运动。 相似文献
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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
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本文首先将层板横截面分为含裂尖区、韧带区以及裂纹区等三个区域,用复变函数理论与特征函数层开法,得到了各区内满足所有基本方程、裂纹表面边界条件与层间连续条件的位移与应力的特征展开式,然后利用分区广义变分原理满足裂纹表面边界以外的边界条件以及各区之间的交界条件,并由此求得奇异场控制量。 相似文献
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本文提出了一种三维-二维混合分区有限元方法分析复合材料层合结构。构造了三维-二维过渡元素和三维的十七节点复合元素。本方法在大大地减少了自由度,缩短了计算时间。算例表明,计算结果令人满意。本方法是可靠的并同样适用于其它结构。 相似文献
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对含有不同切口损伤的复合材料层合板试件进行了拉伸试验,采用电阻应变计同步测量切口损伤前缘区域随载荷的变化,测定含切口损伤层合板的剩余强度,并讨论了损伤长度和损伤角度对剩余强度的影响规律.建立含切口损伤复合材料层合板有限元模型,分析了含切口损伤复合材料层合板的拉伸失效行为,计算了含切口损伤复合材料层合板的剩余强度,确定了剩余强度与切口损伤状态的关系.计算结果与试验结果具有较好的一致性. 相似文献
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LuPin ChenHaibo 《Acta Mechanica Solida Sinica》2005,18(2):130-141
In the present paper, closed form singular solutions for an infinite anisotropic plate with an elliptic hole or crack are derived based on the Stroh-type formalism for the general anisotropic plate. With the solutions, the hoop stresses and hoop moments around the elliptic hole as well as the stress intensity factors at the crack tip under concentrated in-plane stresses and bending moments are obtained. The singular solutions can be used for approximate analysis of an anisotropic plate weakened by a hole or a crack under concentrated forces and moments.They can also be used as fundamental solutions of boundary integral equations in BEM analysis for anisotropic plates with holes or cracks under general force and boundary conditions. 相似文献
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文章研究了含椭圆夹杂的各向异性体的二维变形问题,通过Stroh方法及积分方程法确定了介质及夹杂的弹性场。并在此基础上着重分析了受多项式荷载作用的二维介质的平衡问题,证明了夹杂内部的应力应变场能表示成坐标的同阶多项式形式,以二次多项式荷载为例,获得了夹杂周围介质内的应力扰动现象及环向应力分布。 相似文献
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压电层合板结构振动控制的有限元法 总被引:11,自引:0,他引:11
利用有限元方法模拟压电结构的振动控制,从Hamilton理论出发推导出具有压电传感器及激励器的层合板的电耦合动力方程,应用Lyapunov及负速度反馈控制算来实现振动的控制。 相似文献
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Hu Yiantai Huang Yuying Chen Chuanyao Zhong Weifang 《Acta Mechanica Solida Sinica》2000,13(2):149-154
By using Stroh's formalism and the conformal mapping technique, we derive the simple explicit elastic fields of a generalized
line dislocation and a generalized line force in a general anisotropic piezoelectric strip with fixed surfaces, which are
two fixed conductor electrodes. The solutions obtained are usually considered as Green's functions which play important roles
in the boundary element methods. The Coulomb forces of the distributed charges along the region boundaries on the line chargeq atz
0 are analysed in detail. The results are valid not only for plane and antiplane problems but also for the coupled problems
between inplane and outplane deformations. 相似文献
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The series composed by beam mode function is used to approximate the displacement function of constrained damping of laminated cantilever plates, and the transverse deformation of the plate on which a concentrated force is acted is calculated using the principle of virtual work.By solving Lagrange's equation, the frequencies and model loss factors of free vibration of the plate are obtained, then the transient response of constrained damping of laminated cantilever plate is obtained, when the concentrated force is withdrawn suddenly.The theoretical calculations are compared with the experimental data, the results show:both the frequencies and the response time of theoretical calculation and its variational law with the parameters of the damping layer are identical with experimental results.Also, the response time of steel cantilever plate, unconstrained damping cantilever plate and constrained damping cantilever plate are brought into comparison, which shows that the constrained damping structure can effectively suppress the vibration. 相似文献
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对称铺设正交各向异性层合板的亚谐参数共振 总被引:2,自引:0,他引:2
本文应用奇异性理论讨论了对称铺设正交各向异性层合矩形板的亚谐参数共振问题。主要内容是用Liapunov-Schmidt方法结合Z2-对称等变的概念,使分叉方程转化为代数方程的研究,同时给出了参数平面上不同参数域中各种可能的分叉曲线。 相似文献
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FURTHER STUDIES ON STROH-TYPE FORMALISMS FOR ANISOTROPIC PLATES WITH BENDING-EXTENSION COUPLING 总被引:1,自引:0,他引:1
Pin Lu HaiBo Chen 《Acta Mechanica Solida Sinica》2007,20(4):324-332
Stroh-type formalisms for anisotropic thin plates in literature are reviewed and dis- cussed,and two kinds of hybrid Stroh-type formalisms are compared.It is seen that the two Stroh- type formalisms are essentially equivalent.With simple transfer relations,they can be expressed each other.In addition,with properly defined notation systems,the two Stroh-type formalisms can also be written in unified forms,which will be convenient in applications. 相似文献
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By using Stroh's formalism and the conformal mapping technique, this paper derives simple explicit Green's functions of a
piezoelectric anisotropic body with a free or fixed hyperbolic boundary. The corresponding elastic fields in the medium are
obtained, too. In particular, degenerated solutions of an external crack from those of a hyperbolic problem are analysed in
detail. Then the singular stress fields and the fracture mechanics parameters are found. The solutions obtained are valid
not only for plane and antiplane problems but also for the coupled ones between inplane and outplane deformations. 相似文献
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Xiangying Guo Wei Zhang Minghui Yao 《Acta Mechanica Solida Sinica》2011,24(5):383-398
This paper presents an analysis on the nonlinear dynamics and multi-pulse chaotic motions of a simply-supported symmetric cross-ply composite laminated rectangular thin plate with the parametric and forcing excitations. Firstly, based on the Reddy’s third-order shear deformation plate theory and the model of the von Karman type geometric nonlinearity, the nonlinear governing partial difirential equations of motion for the composite laminated rectangular thin plate are derived by using the Hamilton’s principle. Then, using the second-order Galerkin discretization, the partial differential governing equations of motion are transformed to nonlinear ordinary differential equations. The case of the primary parametric resonance and 1:1 internal resonance is considered. Four-dimensional averaged equation is obtained by using the method of multiple scales. From the averaged equation obtained here, the theory of normal form is used to give the explicit expressions of normal form. Based on normal form, the energy phase method is utilized to analyze the global bifurcations and multi-pulse chaotic dynamics of the composite laminated rectangular thin plate. The theoretic results obtained above illustrate the existence of the chaos for the Smale horseshoe sense in a parametrical and forcing excited composite laminated thin plate. The chaotic motions of the composite laminated rectangular thin plate are also found by using numerical simulation, which also indicate that there exist different shapes of the multi-pulse chaotic motions for the composite laminated rectangular thin plate. 相似文献