检索结果-南通市图书馆

Theoretical & Applied Mechanics Letters 2011年第6期1卷 14-17页

作者： Xiaofei Hu,1 Weian Yao,1, ) and Zhaoxiang Fang2 1)State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian 116024, China 2)Navigation College, Wuhan University of Technology, Wuhan 430063, China Navigation College Wuhan University of Technology Wuhan 430063 China

Symplectic approach has emerged a popular tool in dealing with elasticity problems especially for those with stress singularities. However, anisotropic material problem under polar coordinate system is still a bottleneck. This paper presents a subfield method coupled with the symplectic approach to study the anisotropic material under antiplane shear deformation. anisotropic material around wedge tip is considered to be consisted of many subfields with constant material properties which can be handled by the symplectic approach individually. In this way, approximate solutions of the stress and displacement can be obtained. Numerical examples show that the present method is very accurate and efficient for such wedge problems. Besides, this paper has extended the application of the symplectic approach and provides a new idea for wedge problems of anisotropic material.

关键词： anisotropic material symplectic approach antiplane stress singularity

Equivalent strain hardening exponent of anisotropic materials based on spherical indentation response

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2019年第1期29卷 77-87页

作者： Yu HUI Jian-jun WU Ming-zhi WANG Xue-peng ZHAN He FAN School of Mechanical Engineering Northwestern Polytechnical University Xi’an 710072 China

Uniaxial strain hardening exponent is not suitable for describing the strain hardening behaviors of the anisotropic materials, especially when material deforms in the multi-axial stress states. In this work, a novel method was proposed to estimate the equivalent strain hardening exponent of anisotropic materials based on an equivalent energy method. By performing extensive finite element (FE) simulations of the spherical indentation on anisotropic materials, dimensionless function was proposed to correlate the strain hardening exponent of anisotropic materials with the indentation imprint parameters. And then, a mathematic expression on the strain hardening exponent of anisotropic materials with the indentation imprint was established to estimate the equivalent strain hardening exponent of anisotropic materials by directly solving this dimensionless function. Additionally, Meyer equation was modified to determine the yield stress of anisotropic materials. The effectiveness and reliability of the new method were verified by the numerical examples and by its application on the TC1M engineering material.

关键词： equivalent strain hardening exponent anisotropic material spherical indentation residual imprint

Elliptical inclusion in an anisotropic plane:non-uniform interface effects

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2022年第5期43卷 667-688页

作者： Pengyu PEI Ming DAI School of Electrical and Mechanical Engineering Jinling Institute of TechnologyNanjing 211169China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

We study the plane deformation of an elastic composite system made up of an anisotropic elliptical inclusion and an anisotropic foreign matrix surrounding the *** order to capture the influence of interface energy on the local elastic field as the size of the inclusion approaches the nanoscale,we refer to the Gurtin-Murdoch model of interface elasticity to describe the inclusion-matrix interface as an imaginary and extremely stiff but zero-thickness layer of a finite stretching *** opposed to isotropic cases in which the effects of interface elasticity are usually assumed to be uniform(described by a constant interface stretching modulus for the entire interface),the anisotropic case considered here necessitates non-uniform effects of interface elasticity(described by a non-constant interface stretching modulus),because the bulk surrounding the interface is *** this end,we treat the interface stretching modulus of the anisotropic composite system as a variable on the interface curve depending on the specific tangential direction of the *** then devise a unified analytic procedure to determine the full stress field in the inclusion and matrix,which is applicable to the arbitrary orientation and aspect ratio of the inclusion,an arbitrarily variable interface modulus,and an arbitrary uniform external loading applied *** non-uniform interface effects on the external loading-induced stress distribution near the interface are explored via a group of numerical *** is demonstrated that whether the nonuniformity of the interface effects has a significant effect on the stress field around the inclusion mainly depends on the direction of the external loading and the aspect ratio of the inclusion.

关键词： elliptical inclusion anisotropic material interface stress Gurtin-Murdoch model membrane-type interface

Solution of two-dimensional scattering problem in piezoelectric/piezomagnetic media using a polarization method

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2008年第12期29卷 1535-1552页

作者：胡杨凡王彪 Department of Applied Mechanics and Engineering Sun Yat-sen University School of Physics and Engineering Sun Yat-sen University

Using a polarization method, the scattering problem for a two-dimensional inclusion embedded in infinite piezoelectric/piezomagnetic matrices is investigated. To achieve the purpose, the polarization method for a two-dimensional piezoelectric/piezomagnetic ＂comparison body＂ is formulated. For simple harmonic motion, kernel of the polarization method reduces to a 2-D time-harmonic Green＇s function, which is obtained using the Radon transform. The expression is further simplified under conditions of low frequency of the incident wave and small diameter of the inclusion. Some analytical expressions are obtained. The analytical solutions for generalized piezoelectric/piezomagnetic anisotropic composites are given followed by simplified results for piezoelectric composites. Based on the latter results, two numerical results are provided for an elliptical cylindrical inclusion in a PZT-5H-matrix, showing the effect of different factors including size, shape, material properties, and piezoelectricity on the scattering cross-section.

关键词： scattering piezoelectric/piezomagnetic material polarization method dynamic Green's function two-dimensional problem Radon transform anisotropic material

Natural Frequency of Full-Prestressed Concrete Beam

在线全文

学校读者我要写书评

暂无评论

Transactions of Tianjin University 2007年第5期13卷 354-359页

作者：张耀庭李瑞鸽 School of Civil Engineering and Mechanics Huazhong University of Science and Technology Civil Engineering Department Pingdingshan Institute of TechnologyPingdingshan 467001China

Dynamic tests of three bonded and two unbonded full-prestressed concrete beams were carried *** purpose was to seek the relation between prestressing force and natural *** results indicate that the frequency of prestressed concrete(PSC)beam increases with the increase in prestressing force *** results are different from the dynamic characteristics of isotropic material beam subjected to compressive axial force which were put forward by Clough et *** reason is that the beams were considered as isotropic,homogeneous,linear elastic material in the traditional analysis ***,more accurate results are required in the analysis of frequency of PSC *** constitutive mode of PSC member is analyzed based on microstructure of concrete in this *** orthotropic linear elastic mode is used to analyze the relation between dynamic frequency and prestressing force of concrete beam,at the same time the equivalent stiffness of prestressed tendon relating to the prestressing force is added to the bending deformation stiffness of the *** analytical value agrees well with the test result,indicating that the current analysis method in this paper is feasible to full-prestressed concrete beam.

关键词： full-prestressed concrete beam prestressing force natural frequency anisotropic material

A NEW METHOD FOR ESTABLISHING PSEUDO ORTHOGONAL PROPERTIES OF EIGENFUNCTION EXPANSION FORM IN FRACTURE MECHANICS

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2004年第4期17卷 283-289页

作者： OuZhuocheng ChenYiheng SchoolofCivilEngineeringandMechanics StateKeyLaboratoryofMSSVXi＇anJiaotongUniversityXi＇an710049China SchoolofCivilEngineeringandMechanics StateKeyLaboratoryofMSSVXi＇anJiaotongUniversityXi＇an710049China

A new and simple method is developed to establish the pseudo orthogonal properties (POP) of the eigenfunction expansion form (EEF) of crack-tip stress complex potential functions for cracked anisotropic and piezoelectric materials, respectively. Di?erent from previous research, the complex argument separation technique is not required so that cumbersome manipulations are avoided. Moreover, it is shown, di?erent from the previous research too, that the orthogonal properties of the material characteristic matrices A and B are no longer necessary in obtaining the POP of EEF in cracked piezoelectric materials. Of the greatest signi?cance is that the method presented in this paper can be widely extended to treat many kinds of problems concerning path- independent integrals with multi-variables.

关键词： eigenfunction expansion form pseudo orthogonal properties Bueckner integral weight function piezoelectric material anisotropic material

Analysis of Surface Acoustic Waves in Finite Elastic Plates Covered by A Thin Metal Layer

在线全文

学校读者我要写书评

暂无评论

Analysis of Surface Acoustic Waves in Finite Elastic Plates ...

EQUIVALENT CONTINUUM MODEL FOR JOINTED ROCKS

第二届全国压电和声波理论及器件技术研讨会

作者： Huimin Mao~1,Ji Wang~2 (1.School of Energy Resources and Power Engineering,Jiangsu University,Zhenjiang 212013,P.R.China 2.School of Mechanical Engineering,Ningbo University,Ningbo 315211,P.R.China)

Surface acoustic waves exist in semi-infinite elastic solids only is known as Rayleigh waves, but engineering applications with finite plates and extra complications like metal plantings for layered structures are common and surface acoustic waves are utilized in a practical and general *** analysis of surface acoustic waves in elastic solids started from isotropic half-space with solutions and techniques dated back to Lord *** the analysis of surface acoustic wave,make full use of Matlab software. Now extend the theory to finite solids covered by a thin metal *** theory and method from this study can be directly applied to the analysis and design of surface acoustic wave resonators with accuracy and convenience.

关键词： Surface acoustic wave Finite plate Isotropic material anisotropic material

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

EQUIVALENT CONTINUUM MODEL FOR JOINTED ROCKS

WAVES IN PLATES OF anisotropic FUNCTIONALLY GRADED materialS

岩石力学与环境岩土工程国际会议

作者： Bao Changhan and Tao Zhenyu (University of Hydraulic and Electric Power/Yichang Yyichang 443002 P.R.China)

＜正＞The equivalent cotinuum model to be applied to asertain the constitutive of two or three dimensional problem in rock is presented in this *** the model,the rock cut by joints is treated as anisotropic material, the discontinuity of rock and irregularity of joint intermission are also can be simulated.A multi-lamina model is used to analyses rock mass strength. The rock’s mechanical properties and stress distribution is take into accont.

关键词： jointed rock anisotropic material equivalent continuum strength analyysis constitutive

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

WAVES IN PLATES OF ANISOTROPIC FUNCTIONALLY GRADED MATERIALS

Laser-generated thermoelastic acoustic sources and acoustic waves in anisotropic plate

庆祝中国力学学会成立50周年暨中国力学学会学术大会’2007

作者： CHEN Weiqiu~(1)) GUO Yongqiang (Department of Civil Engineering Zhejiang University,Hangzhou 310027,China)

Theory of wave propagation in materials and structures is essential to many applications such as material property characterization and damage *** the emergence of functionally graded materials(FGMs) in 1980s,many efforts have been done to understand the wave propagation characteristic in FGM plates and shells, whose material properties vary with spatial coordinates continuously.A usual way is to divide the FGM plate or

关键词： functionally graded material anisotropic material state equation method of reverberation-ray matrix dispersion

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

中国科学:技术科学 2010年第3期 321-321页

作者： XU BaiQiang,WANG Feng,FENG Jun,WANG JiJun,SUN HongXiang & LUO Ying Faculty of Science,Jiangsu University,Zhenjiang 212013,China

The effect of anisotropy on the ultrasound wave generation and propagation in the unidirectional fiber-reinforced composite plate has been investigated.A quantitative numerical model for the laser-generated ultrasound in the thermoelastic regime was presented by using a finite element *** factors,such as spatial and time distributions of the incident laser beam,optical penetration,thermal diffusivity,and source-receiver distance can be taken into *** results show that the effect on ultrasound waveform of the size of the laser volume source produces strong bipolar longitudinal waves and improves the amplitude and directivity of the longitudinal waves.A fiber-reinforced composite material exhibits isotropic or homogenous behavior for ultrasonic wave propagation perpendicular to the fiber *** ultrasonic propagation along the fiber direction,ultrasonic dispersion resulting from the inhomogeneous nature of the material affects the laser ultrasonic *** the dimensions of the laser pulse are increased in space and time,the displacement waveform becomes broader and its magnitude decreases.

关键词： laser ultrasound numerical simulation anisotropic material