变厚度梁板结构的弹性静力学分析
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摘要
本文基于小变形的精确线弹性理论,不引入任何人为假设,研究了变厚度梁板结构的弹性静力学特性。首先,对于简支边界条件,利用傅立叶级数展开法,分别给出了任意载荷作用下两端简支变厚度梁的二维弹性力学解和四边简支变厚度矩形板的三维弹性力学解。其次,对于非简支边界条件,以固支边为例,通过引入单位脉冲函数,采用边界松弛法,给出了一端固支一端简支变厚度梁的弹性力学解。最后,将这种方法推广应用,研究了在热荷载与机械荷载共同作用下各向同性材料、正交各向异性材料、功能梯度材料、压电材料变厚度梁和变厚度矩形板的弯曲问题。
     具体的说,本文的主要内容包括:
     (1)对于两端简支变厚度梁,从二维平面弹性力学的基本方程出发,导出满足控制微分方程和两端简支边界条件的位移函数一般解,对梁上下表面的边界方程作傅立叶级数展开确定待定系数。
     (2)对于四边简支变厚度矩形板,从三维弹性力学的基本方程出发,导出满足控制微分方程和四边简支边界条件的位移函数一般解,对板上下表面的边界方程作双重傅立叶正弦级数展开确定待定系数。
     (3)对于一端固支一端简支变厚度梁,引入单位脉冲函数和Dirac函数,将固支边等价为简支边加上水平方向的未知边界力,求得其精确解析解,对梁上下表面的边界方程作傅立叶级数展开并与固支边位移为零的条件共同确定未知系数。
     (4)对于功能梯度材料,假设弹性模量沿厚度方向指数变化,泊松比为常数,首先求得简支边界条件下控制微分方程的解析解,然后对结构上下表面的边界方程作傅立叶级数展开,分析了两端简支变厚度功能梯度梁和四边简支变厚度功能梯度矩形板的弯曲问题。
     (5)对于压电材料,首先求解简支边界条件下精确满足控制微分方程的结构位移场和压电场,然后对结构上下表面的边界方程作傅立叶级数展开,分析了两端简支变厚度压电梁和横观各向同性四边简支变厚度压电矩形板的弯曲问题。
     (6)对于受温度作用的两端简支变厚度梁和四边简支变厚度板,首先根据温度的边界条件,采用傅立叶正弦级数展开求解梁和板内的温度分布,然后再将温度荷载施加于梁和板上,给出了机械荷载与热荷载共同作用下变厚度梁的二维热弹性力学解和变厚度矩形板的三维热弹性力学解。
     (7)对于多跨的板结构,首先求得满足控制微分方程和四边简支边界条件的矩形板位移函数的一般解,将支承反力看作是作用于板上的待求反力,利用板上下表面的边界方程确定待定系数。给出了点支、线支和弹性地基上简支矩形板以及面内受线支作用的功能梯度矩形板的三维弹性力学解。
This thesis studies the static properties of beams and plates with variable thickness, based on the small-strain linear elasticity theory which does not rely on any artificial hypotheses. Firstly, for the simple-supported boundary conditions, the two-dimensional elasticity solution of simple-supported beams with variable thickness and the three-dimensional elasticity solution of simple-supported rectangular plates with variable thickness under arbitrary loads are presented by using the Fourier series expansion method. Then, for the non-simply-supported boundary conditions, the clamped boundary condition is taken as an example. The elasticity solution of varying thickness beams with one end clamped and the other end simply supported under static loads are presented by introducing the unit pulse functions and using the boundary relaxation method. Finally, the Fourier series expansion method is extended to study the bending problem of beams with variable thickness and rectangular plates with variable thickness, subjected to thermo-mechanical load where the beams and the plates are, respectively, made of isotropic materials, orthotropic materials, functionally graded materials and piezoelectric materials.
     The detailed contents of the thesis are given as follows:
     (1) On the basis of the two-dimensional plane elasticity theory, the general expressions of displacements, which exactly satisfy the governing differential equations and the simply-supported boundary conditions at two ends of the beam, have been deduced. The unknown coefficients in the solution are then determined by using the Fourier sinusoidal series expansion to the boundary equations on the upper and lower surfaces of the beams.
     (2) On the basis of three-dimensional elasticity theory, the general expressions for displacements and stresses of the rectangular plate under static loads, which exactly satisfy the governing differential equations and the simply-supported boundary conditions at four edges of the plate, are analytically derived. The unknown coefficients in the stress solutions are approximately determined by using the double Fourier sinusoidal series expansions to the boundary conditions on the upper and lower surfaces of the plates.
     (3) For the varying thickness beams with one end clamped and the other end simply-supported, by introducing the unit pulse functions and Dirac functions, the clamped edge can be made equivalent to the simply supported one by adding the unknown horizontal reactions. Then the exact analytical solution is obtained. The unknown coefficients can be determined by using the Fourier sinusoidal series expansion along the upper and lower boundaries of the beams and using the condition of zero displacements at the clamped edge.
     (4) For the functionally graded materials, the Young's modulus is graded through the thickness following the exponential-law and the Poisson's ratio keeps constant. Firstly, the analytical solution of the governing differential equations can be obtained. Then using the Fourier sinusoidal series expansions to the boundary conditions on the upper and lower surfaces of the structures, the bending problem of simply-supported functionally graded beams with variable thickness and simply-supported functionally graded rectangular plates with variable thickness are studied.
     (5) For the piezoelectric materials, the general expressions of displacement fields and piezoelectric field, which exactly satisfy the governing differential equations and the simply-supported boundary conditions, are derived firstly. The unknown coefficients in the solution are then determined by using the Fourier sinusoidal series expansion to the boundary equations on the upper and lower surfaces of the structures. The bending problem of simply-supported piezoelectric beams with variable thickness and simply-supported transversely isotropic piezoelectric rectangular plates with variable thickness are studied.
     (6) For the simple-supported beam with variable thickness and simple-supported rectangular plate with variable thickness under the temperature field, we need to solve the temperature distributions on beam and plate by using Fourier sinusoidal series expansions according to the temperature boundary condition at first. Then the temperature load is exerted to the beam and the plate. The two-dimensional thermoelastic analysis of beams with variable thickness subjected to thermo-mechanical loads and the three-dimensional thermoelastic analysis of rectangular plates with variable thickness subjected to thermo-mechanical loads are presented.
     (7) For the multi-span plates, the exact expressions of the displacements, which satisfy the governing differential equations and the simply supported boundary conditions at four edges of the plate, are analytically derived firstly. The reaction forces of the intermediate supports are regarded as the unknown external forces acting on the lower surface of the plate. The unknown coefficients are then determined by the boundary conditions on the upper and lower surfaces of the plate. Three-dimensional elasticity solution of simple-supported rectangular plate on point supports, line supports and elastic foundation are studied and the simply-supported functionally graded rectangular plates with internal elastic line supports are also presented.
引文
[1]S.铁木辛柯,J.盖尔.材料力学[M].科学出版社,1978.
    [2]徐芝纶.弹性力学[M].高等教育出版社,1982.
    [3]梅甫良,曾德顺.深梁的精确解[J].力学与实践,2002,24(3):58-60.
    [4]梅甫梁.两端固支深梁弯曲问题的解析解.强度与环境,2003,30(3):23-28.
    [5]Ding H J, Huang D J, Wang H M. The analytical solution for fixed-end beam subjected to uniform load. Journal of Zhejiang University, Science A.2005,6(8):779-783.
    [6]Huang D J, Ding H J, Wang H M. Analytical solution for fixed-end orthotropic beams subjected to uniform load. Journal of Zhejiang University, Science A.2006,40(3):511-514.
    [7]Ding H J, Huang D J, Wang H M. The analytical solution for fixed-fixed anisotropic beams subjected to uniform load. Applied Mathematics and Mechanics,2006,27(10):1305-1310.
    [8]Jiang A M, Ding H J. The analytical, solutions for orthotropic cantilever beams (I):Subjected to surface forces. Journal of Zhejiang University, Science A,2005,6(2):126-131.
    [9]Chen W Q, Lu C P, Bian Z G. A mixed method for bending arid free vibration of beams rest ing on a Pasternak elastic foundation. Applied Mathematical Model ling,2004,28,877-890.
    [10]Srinivas S, Rao A K. Bending, vibration and buckling of simply supported thick orthotropic rectangular plates and laminates. International Journal of Solids and Structure,1970,6,1463-1481.
    [11]Srinivas S, Rao C V, Rao A K. An exact analysis for vibration of simply supported homogeneous and laminated thick rectangular plates. Journal of Sound and Vibration,1970,12,187-199.
    [12]Wang Y M, Tarn J Q. Three-dimensional analysis of anisotropic inhomogeneous and laminated plates. International Journal of Solids and Structure,1994,31,497-515.
    [13]Fan J R and Ye J Q. A series solution of the exact equation for thick orthotropic plates. International Journal of Solids and Structures. 1990,26(7):773-778.
    [14]Fan J R and Sheng H Y. Exact solution for thick laminate with clamped edges. Acta Mechanica Sinica.1992,24(5):574-583.
    [15]范家让.强厚度叠层板壳的精确理论[M].科学出版社,1996.
    [16]Sheng H Y, Ye J Q. A semi-analytical finite element for laminated composite plates.2002,57:117-123.
    [17]Sheng H Y, Ye J Q. A state space finite element for laminated composite plates. Computer Methods in Applied Mechanics and Engineering.2002, 191:4259-4276.
    [18]Ding H J and Xu R Q. Free axisymmetrie vibration of laminated transversely isotropic annular plates. Journal of Sound and Vibration,2000,230(5):1031-1044.
    [19]Sankar B V. An elastic solution for functionally graded beams Composite Seience and Technoly.200.1,61. (5):689-696.
    [20]Zhu H and Sankar B V. A combined Fourier-Galerkin method for the analysis of functionally graded beams. Journal of Applied Mechanic 2004,71(3):421-424.
    [21]Ding H J, Huang D J, Chen W Q. Elastieity solutions for plane anisotropic functionally graded beams. International Journal of Solids and Structures.2007,44:176-196.
    [22]仲政,于涛.功能梯度悬臂梁弯曲问题的解析解.同济大学学报:自然科学版.2006,34(4):443-447.
    [23]于涛,仲政.均布荷载作用下功能梯度悬臂梁弯曲问题的解析解.固体力学学报.2006,27(1):15-20.
    [24]Zhong Z and Yu T. Analytical solution of a cantilever functionally graded beam. Composite Science and Techanoly.2007,67:481-488.
    [25]Ying J, Lu C F, Chen W Q. Two-dimensional elasticity solutions for functionally graded beams resting on elastic foundations [J]. Composite Structures,2008,84:209-219.
    [26]黄德进,丁皓江,陈伟球.线性分布荷载作用下功能梯度各向异性悬臂梁的解析解.应用数学和力学.2007,28(7):763-768.
    [27]黄德进,丁皓江,陈伟球.任意荷载作用下各向异性功能梯度悬臂梁的解析解和半解析解.中国科学G辑:物理学力学天文学.2009,39(6):830-842.
    [28]Chi S H, Chung Y L. Mechanical behavior of functionally graded material plates under transverse load-part Ⅰ:Analysis. International Journal of Solids and Structures.2006,43:3657-3674.
    [29]Chi S H, Chung Y L. Mechanical behavior of functionally graded material plates under transverse load-part II:Numerical results. International Journal of Solids and Structures.2006,43:3675-3691.
    [30]刘进,武兰河,张晓炜.功能梯度材料板的弯曲问题.石家庄铁道学院学报.2003,16(2):1-5.
    [31]Reddy J N. Analysis of functionally graded plates. International Journal for Numerical Methods in Engineering.
    [32]Redd J N, Wang C M, Kitipornchai S. Axisymmetric bending of functionally graded circular and annular plates. European Journal of Mechanics-A/Solids.1999,18:185-199.
    [33]Ma L S, Wang T J. Relationships between axisymmetric bending and buckling solutions of functionally graded circular plates based on third-order plate theory and classical plate theory. International Journal of Solids and Structures.2004,41:85-101.
    [34]杨正光,仲政,戴瑛.功能梯度矩形板的三维弹性分析.力学季刊.2004,25(1):15-20.
    [35]Kashtalyan M. Three-dimensional elastic solutions for bengding of functionally graded rectangular plates. European Journal of Mechanics A/Solids.2004,23:853-864.
    [36]Huang Z Y, Lu C F, Chen W Q. Benchmark solutions for functionally graded thick plates resting on Winkler-Pasternak elastic foundations. Composite Structures,2008,85:95-104.
    [37]Nie G J, Zhong Z. Semi-analytical solution for three-dimensional vibration of functionally graded circular plates. Computer methods in applied mechanics and engineering.2007,196:4901-4910.
    [38]林启荣,刘正兴,金占礼.均布荷载作用下两端简支压电梁的解析解.应用数学和力学.2000,21(6):617-624.
    [39]杨德庆,刘正兴.自由端受集中力作用下压电悬臂梁弯曲问题的解析解.力学季刊.2003,24(3):327-333.
    [40]柳拥军,杨德庆.均布荷载作用下压电悬臂梁弯曲问题的解析解.固体力学学报,2002,23(3):366-371.
    [41]Li Y, Shi Z F. Free vibration of a functionally graded piezoelectric beam via state-spa.ce based differential quadrature. Composite Structures.2009,87:257-264. [42] Bisegna P, Maceri F. An exact three-dimensional solution for simply supported rectangular piezoelectric plates. ASME, Journal of Applied Mechanics.1996,63:628-638. [43] Zhong Z, Shang E T. Three-dimensional exact analysis of a simply supported functionally gradient piezoelectric plate. International Journal of Solids and Structures.2003,40:5335-5352. [44] Sheng H Y, Wang H, Ye J Q. State space solution for thick laminated piezoelectric plates with clamped and electric open-circuited boundary conditions. International Journal of Mechanical Science. 2007,49:806-818.
    [45]陈伟球,梁剑,丁皓江.压电复合材料矩形厚板弯曲的三维分析.复合材料学报,1997,14:108-115.
    [46]Chen W Q, Xu R Q, Ding H J. On free vibration of a piezoelectric composite rectangular plate. Journal of Sound and Vibration.1998, 218:741-748.
    [47]Nowacki W. Thermoelasticity. New York:Pergamon Press,1952.
    [48]吕朝锋.陈伟球,仲政.功能梯度厚梁的二维热弹性力学解.中国科学G辑,2006,36(4):384-392.
    [49]刘五祥,仲政.功能梯度平板的二维热弹性分析.力学季刊.2008,29(1):4047.
    [50]陈伟球,丁皓江.横观各向同性三维热弹性力学通解及其势理论法.力学学报.2003,35(5):578-583.
    [51]陈伟球,边祖光,丁皓江.功能梯度矩形厚板的三维热弹性分析.力学季刊,2002,23(4):443-449.
    [52]Vel S S, Batra R C. Exact solution for thermo-elastic deformations of functionally graded thick rectangular plates. American Institute of Aeronautics and Astronautics.2002,40:1421-1433.
    [53]Ootao Y, Tanigawa Y. Three-dimensional solution for transient thermal stresses of an orthotropic functionally graded rectangular plate. Composite Structures.2007,80:10-20.
    [54]Zenkour A M. Analytical solution for bending of cross-ply laminated plates under thermo-mechanical loading. Composite structures.2004, 65:367-379.
    [55]Alibeigloo A. Exact solution for thermo-elastic response of functionally graded rectangular plates. Composite Structures.2010, 92:113-121.
    [56]周叮.两对边简支中间有任意多个单向弹性线支矩形板横向振动的一个解析解法.应用数学与力学,1996,17(8):729-734
    [57]刘俊聊,王克林.弹性地基上四边自由的各向异性矩形板.应用力学学报,2003,20(3):103-106
    [58]孙卫明,杨光松,张承宗.双参数地基上弹性厚板弯曲的一般解析解.工程力学,1999,16(2):71-78
    [59]Zhou D, Cheung Y K. Free vibration of line supported rectangular plates using a set of static beam functions. J Sound Vib,1999,223(2): 231-245
    [60]Cheung Y K, Zhou D. Free vibration of rectangular unsymmetrically laminated composite plates with internal line supports. Comput Struct,2001,79(21):1923-1932
    [61]Zhou D, Ji T J. Free vibration of rectangular plates with internal column supports. J Sound Vib,2006,297(1):146-166
    [62]Huang M H and Thambiratnam D P. Analysis of plate resting on elastic supports and elastic foundation by finite strip method. Comput Struct, 2001,79,2547-2557.
    [63]刘庆潭.含楔形变截面梁静力分析的传递矩阵法求解.力学与实践,1993,15(1): 64-66.
    [64]Jang S K, Bert C W. Free vibration of stepped beams:exact and numerical solutions. Journal of Sound and Vibration.1989,130: 342-346.
    [65]Jang S K, Bert C W. Free vibration of stepped beams:Higher mode frequencies and effects of steps on frequencies. Journal of Sound and Vibration.1989,32:164-168.
    [66]Ece M C, Aydogdu M, Taskin V. Vibration of a variable cross-section beam. Mechanics Research Communications.2007,34:78-84.
    [67]Huang Y, Li X F. A new approach for free vibration of axially functionally graded beams with non-uniform cross-section. Journal of Sound and Vibration.2010,329:2291-2303.
    [68]Xiang H J, Yang J. Free and forced vibration of a laminated FGM Timoshenko beam of variable thickness under heat conduction. Composite:Part B.2008,39:292-303.
    [69]Conway H D. Axially symmetric plates with linearly varying thickness. ASME Journal of Applied Mechanics,1951,18:140-152.
    [70]Conway H D. Closed form solutions for plates of variable thickness. ASME Journal of Applied Mechanics,1953,20:564-575.
    [71]Ohga M, Shigematsu T. Bending analysis of plates with variable thickness by boundary element-transfer matrix method. Computers and Structures,1988,28:635-641.
    [72]Zenkour A M. An exact solution for the bending of thin rectangular plates with uniform, linear, and quadratic thickness variations. International Journal of Mechanical Science,2003,45:295-315.
    [73]Nerantzaki M S, Katsikadelis J T. Buckling of plates with variable thickness—an analog equation solution. Engineering Analysis with Boundary Elements.1996,18:149-54.
    [74]Ashour A S. A semi-analytical solution of the flexural vibration of orthotropic plates of variable thickness. Journal of Sound and Vibration.2001,240:431-445.
    [75]Liew K M, Lim C M, Lim M K, Transverse vibration of trapezoidal plates of variable thickness:unsymmetric trapezoids. Journal of Sound and Vibration.1994,177:479-501.
    [76]Lim C M, Liew K M. Effects of boundary constraints and thickness variation on the vibratory response of rectangular plates. Thin-Walled Structures.1993,17:133-159.
    [77]Liew K M, Ng T Y, Kitipornchai S. A semi-analytical solution for vibration of rectangular plates with abrupt thickness variation. International Journal of Solids and Structures.2001,38:4937-4954.
    [78]Huang M, Ma X Q, Sakiyama T, Matuda H, Morita C. Free vibration analysis of orthotropic rectangular plates with variable thickness and general boundary conditions. Journal of sound and vibration.2005,288: 931-955.
    [79]Zhou D. Vibration of point-supported rectangular plates with variable thickness using a set of static tapered beam functions. International Journal of Mechanical Sciences.2002,44:149-164.
    [80]Kang J H, Leissa A W. Three-dimensional vibrations of thick, linearly tapered, annular plates. Journal of Sound and Vibration.1998,217: 927-944.
    [81]Kang J H. Three-dimensional vibration analysis of thick, circular and annular plates with nonlinear thickness variation. Computers and Structures.2003,81:1663-1675.
    [82]Wang X, Yang J, Xiao J. On free vibration analysis of circular annular plates with non-uniform thickness by the differential quadrature method. Journal of Sound and Vibration.1995,184:547-551.
    [83]Efraim E, Eisenberger M. Exact vibration analysis of variable thickness thick annular isotropic and FGM plates. Journal of Sound and Vibration.2007,299:720-738.
    [84]Sakiyama T, Huang M. Free vibration analysis of right triangular plates with variable thickness. Journal of Sound and Vibration.2000, 234:841-858.
    [85]Zenkour A M, Mashat D S. Exact solutions for variable thickness inhomogeneous elastic plates under various boundary conditions. Meccanica.2009,44:433-447.
    [86]Lekhnitskii S G. Anisotropic plate[M]. Gordon and Breach, New York, 1968.

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