检索结果-南通市图书馆

Bending analysis of a functionally graded piezoelectric cantilever beam

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2007年第1期50卷 97-108页

作者： YU Tao ZHONG Zheng School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China

A new analysis based on Airy stress function method is presented for a functionally graded piezoelectric material cantilever beam. Assuming that the mechanical and electric properties of the material have the same variations along the thickness direction, a two-dimensional plane elasticity solution is obtained for the coupling electroelastic fields of the beam under different loadings. This solution will be useful in analyzing FGPM beam with arbitrary variations of material properties. The influences of the functionally graded material properties on the structural response of the beam subjected to different loads are also studied through numerical examples.

关键词： functionally graded piezoelectric material cantilever beam bending electroelastic fields

Fracture analysis of a functionally graded interfacial zone between two dissimilar homogeneous materials

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2006年第5期49卷 540-552页

作者： CHENG Zhanqi1,2 & ZHONG Zheng1 1. School of Aerospace Engineering and Applied mechanics, Tongji University, Shanghai 200092, China 2. College of Civil Engineering, Zhengzhou University, Zhengzhou 450002, China School of Aerospace Engineering and Applied mechanics Tongji University Shanghai China College of Civil Engineering Zhengzhou University Zhengzhou China

In this paper the plane elasticity problem for a functionally graded interfacial zone containing a crack between two dissimilar homogeneous materials has been considered. It is assumed that in the interfacial zone the reciprocal of the shear modulus is a linear function of the coordinate, while Possion’s ratio keeps constant. By utilizing the Fourier transformation technique and the transfer matrix method, the mixed boundary problem is reduced to a system of singular integral equations that are solved numerically. The influences of the geometric parameters and the graded parameter on the stress intensity factors are investigated. The numerical results show that the graded parameters, the thickness of interfacial zone, the crack size and location have significant effects on the stress intensity factors.

关键词： functionally graded material interfacial zone fracture stress intensity factor

A DECAGONAL QUASICRYSTAL WITH AN ARC-SHAPED CRACK

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2003年第1期16卷 8-15页

作者： Wang Xu Zhong Zheng Tongji Univ Dept Engn Mech & Technol Key Lab Solid Mech Shanghai 200092 Peoples R China

A decagonal quasicrystal, which is weakened by an arc-shaped crackpenetrating through the solid in the period direction, and which is subjected to remote uniformphonon stresses, is investigated by applying the complex variable method which is just developed bythe authors. It is found that the phonon and phason stresses near the crack tips exhibit inversesquare root singularities. The four complex stress functions characterizing the phonon and phasonfields are derived. Explicit expressions for the phonon and phason stress intensity factors, crackopening displacements and energy release rate are also presented.

关键词： decagonal quasicrystal arc-shaped crack stress intensity factor energyrelease rate

ELECTROELASTIC INTENSIFICATION NEAR ANTI-PLANE CRACK IN A FUNCTIONALLY GRADIENT PIEZOELECTRIC CERAMIC STRIP

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2003年第3期16卷 197-204页

作者： Hu Keqiang Zhong Zheng Jin Bo (Solid Mechanics Key Laboratory of MEC,Department of Engineering Mechanics and Technology,Tongji University,Shanghai 200092,China) Solid Mech. Key Laboratory of MEC Dept. of Eng. Mech./Technology Tongji University Shanghai 200092 China

Following the theory of linear piezoelectricity,we consider the electro-elastic prob- lems of a finite crack in a functionally gradient piezoelectric ceramic *** the use of Fourier transforms we reduce the problem to solving two pairs of dual integral *** solution to the dual integral equations is then expressed in terms of a Fredholm integral equation of the second *** calculations are carried out for piezoelectric *** electric field intensity factors and the energy release rate are shown graphically,and the electroelastic interactions are illustrated.

关键词： piezoelectricity crack electroelastic interactions

在线全文

学校读者我要写书评

暂无评论

功能梯度材料涂层平面裂纹分析

力学学报 2007年第5期39卷 685-691页

作者：程站起仲政郑州大学土木工程学院郑州450001 同济大学航空航天与力学学院上海200092

研究粘接于均质基底材料上功能梯度涂层平面裂纹问题.假设功能梯度材料剪切模量的倒数为坐标的线性函数,而泊松比为常数.采用Fourier变换和传递矩阵法将该混合边值问题化为奇异积分方程组,通过数值求解获得应力强度因子.考察了材料梯度... 详细信息

研究粘接于均质基底材料上功能梯度涂层平面裂纹问题.假设功能梯度材料剪切模量的倒数为坐标的线性函数,而泊松比为常数.采用Fourier变换和传递矩阵法将该混合边值问题化为奇异积分方程组,通过数值求解获得应力强度因子.考察了材料梯度变化形式、结构几何尺寸和材料梯度参数对裂纹应力强度因子的影响,发现功能梯度材料涂层尺寸、裂纹长度以及材料梯度参数均对应力强度因子有显著影响.

关键词：功能梯度材料涂层断裂应力强度因子

基于Haar小波方法的功能梯度压电材料矩形板三维力学分析

在线全文

学校读者我要写书评

暂无评论

工程力学 2008年第11期25卷 205-211页

作者：张纯仲政南昌大学建工学院南昌330031 同济大学航空航天与力学学院上海200092

针对任意材料梯度分布形式的四边简支、接地功能梯度压电材料平板,把Haar小波方法引入平板结构的三维分析中。由于小波方法在求解存在局部奇异性问题上的优越性,对于任意材料梯度变化,甚至材料性质存在局部剧烈变化的情况,各分量的Haar... 详细信息

针对任意材料梯度分布形式的四边简支、接地功能梯度压电材料平板,把Haar小波方法引入平板结构的三维分析中。由于小波方法在求解存在局部奇异性问题上的优越性,对于任意材料梯度变化,甚至材料性质存在局部剧烈变化的情况,各分量的Haar小波级数解都有较好的收敛性。通过算例,该文分析了在机械荷载、电荷载分别作用下,材料不同梯度形式、平板上下表面材料性质差异对功能梯度压电平板结构响应的影响。

关键词：功能梯度材料压电材料矩形板 Haar小波三维力学分析

ANTI-PLANE SHEAR CRACK IN A FUNCTIONALLY GRADIENT PIEZOELECTRIC MATERIAL

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2002年第2期15卷 140-148页

作者： Hu Keqiang Zhong Zheng Jin Bo Tongji Univ Dept Engn Mech & Technol Shanghai 200092 Peoples R China

The main objective of this paper is to study the singular natureof the crack-tip stress and electric displacement field in afunctionally gradient piezoelectric medium having materialcoefficients with a discontinuous derivative. The problem isconsidered for the simplest possible loading and geometry, namely,the anti-plane shear stress and electric displacement in -plane oftwo bonded half spaces in which the crack is parallel to theinterface.

关键词： functionally gradient material piezoelectric material stress intensityfactors electric dis- placement intensity factors

An analysis of surface acoustic wave propagation in a plate of functionally graded materials with a layered model

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2008年第2期51卷 165-175页

作者： GAO LiMing WANG Ji ZHONG Zheng DU JianKe College of Aerospace Engineering and Mechanics Tongji UniversityShanghai 200092China Piezoelectric Device Laboratory School of EngineeringNingbo UniversityNingbo 315211China

In a homogeneous plate, Rayleigh waves will have a symmetric and anti-symmetric mode regarding to the mid-plane with different phase velocities. If plate properties vary along the thickness, or the plate is of functionally graded material (FGM), the symmetry of modes and frequency behavior will be modified, thus producing dif-ferent features for engineering applications such as amplifying or reducing the velocity and deformation. This kind of effect can also be easily realized by utilizing a layered structure with desired material properties that can produce these effects in terms of velocity and displacements, since Rayleigh waves in a solid with gen-eral material property grading schemes are difficult to analyze with known methods. Solutions from layered structures with exponential and polynomial property grad-ing schemes are obtained from the layered model and comparisons with known analytical results are made to validate the method and examine possible applica-tions of such structures in engineering.

关键词： Rayleigh wave surface acoustic wave vibration plate layered structure functionally graded material (FGM)

在线全文

学校读者我要写书评

暂无评论

变截面门式刚架结构分析的微分求积单元法

力学季刊 2005年第2期26卷 198-203页

作者：聂国隽仲政同济大学固体力学教育部重点实验室

本文采用一种精确、简便的数值计算方法———微分求积单元法(DQEM)对变截面门式刚架结构进行了力学分析。首先建立了一般荷载作用下变截面构件的平衡微分方程,并采用微分求积法进行离散,进而得出了较为精确的分析变截面构件的单元力学... 详细信息

本文采用一种精确、简便的数值计算方法———微分求积单元法(DQEM)对变截面门式刚架结构进行了力学分析。首先建立了一般荷载作用下变截面构件的平衡微分方程,并采用微分求积法进行离散,进而得出了较为精确的分析变截面构件的单元力学模型。该模型的刚度方程不仅反映了单元的刚度性质,而且反映了单元的实际荷载作用,可较为精确地分析变截面门式刚架结构在分布载荷作用下的受力性能。通过与有限元法计算结果的比较,表明了微分求积单元法在变截面刚架的力学分析中的正确性和优越性。微分求积单元法可用于任意形状的刚架结构的静力分析。

关键词：变截面构件门式刚架结构微分求积单元法