×

Shape optimization in laminated composite plates. (English) Zbl 0675.73059

In view of the lack of information on shape optimization in composite media, it was decided to do a pilot study involving a hole in a laminated plate subject to in-plane biaxial tension. Classical plate lamination theory is used, together with a finite element approach. Minimizing the maximum values of certain failure functions \(\Phi\) is taken to be the objective. In the single-ply case it can be shown that the optimality condition is that the mutual strain energy is constant on the design boundary under the condition that the design boundary has no geometrical constraint [see the second author, K. T. Chung, T. Torigaki and J. E. Taylor, ibid. 57, 67-89 (1986; Zbl 0578.73081); eq. 10; 20]. For isotropic media, it has also been shown that the optimality condition is \(\Phi=\)constant on the hole boundary. This, so far, has not been proven for anisotropic media. Here, analogous to the isotropic case, it is postulated that the maximum value of \(\Phi\) occurs on the hole boundary. At all stages of the numerical work this was monitored numerically and found to be true. Moreover \(\Phi=\)constant on the hole boundary is postulated as the optimality condition. This, in general, will not lead to a global optimum (in view of the possibility of multiple holes), but it should lead to a local minimum. Of particular interest was to see whether the techniques developed for shape optimization in isotropic media would work for laminated composites, involving as they do much larger stress gradients.

MSC:

74P99 Optimization problems in solid mechanics
74S05 Finite element methods applied to problems in solid mechanics
74E30 Composite and mixture properties
74K20 Plates
74S30 Other numerical methods in solid mechanics (MSC2010)

Citations:

Zbl 0578.73081

References:

[1] Haug, E. J., A unified theory of optimization of structures with displacements and compliance constraints, J. Structural Mech., 9, 415-437 (1981)
[2] Haftka, R. T.; Grandhi, R. V., Structural shape optimization—a survey, Comput. Meths. Appl. Mech. Engrg., 57, 91-106 (1986) · Zbl 0578.73080
[3] Choi, K. K.; Haug, E. J., Shape design sensitivity analysis of elastic structures, J. Structural Mech., 11, 231-269 (1983)
[4] Dems, K.; Mroz, Z., Variational approach by means of adjoint systems to structural optimization and sensitivity analysis—I, Internat. J. Solids and Structures, 19, 677-692 (1983) · Zbl 0515.73085
[5] Banichuck, N. V., Optimality conditions in the problem of seeking the hole shapes in elastic bodies, Appl. Math. Mech., 41, 920-925 (1977) · Zbl 0401.73030
[6] Banichuck, N. V., Problems and Methods of Optimal Structural Design (1983), Plenum Press: Plenum Press New York · Zbl 0312.90059
[7] Kikuchi, N.; Chung, K. Y.; Torigaki, T.; Taylor, J. E., Adaptive finite element methods for shape optimization of linearly elastic structures, Comput. Meths. Appl. Mech. Engrg., 57, 67-89 (1986) · Zbl 0578.73081
[8] Diaz, A. R.; Kikuchi, N.; Taylor, J. E., A method of grid optimization for finite element methods, Comput. Meths. Appl. Mech. Engrg., 45, 29-45 (1983) · Zbl 0509.73071
[9] Braibant, V.; Fleury, C., Shape optimal design using B-splines, Comput. Meths. Appl. Mech. Engrg., 44, 247-267 (1984) · Zbl 0525.73104
[10] Braibant, V.; Fleury, C., An approximation-concepts approach to shape optimal design, Comput. Meths. Appl. Mech. Engrg., 53, 119-148 (1985) · Zbl 0562.73084
[11] Kicher, T. P.; Chao, T. L., Minimum weight design of stiffened fiber composite cylinders, J. Aircraft, 8, 562-568 (1971)
[12] Hirano, Y., Optimum design of laminated plates under axial compression, AIAA J., 17, 1017-1019 (1979) · Zbl 0438.73076
[13] Hirano, Y., Optimum design of laminated plates under shear, J. Composite Mat., 13, 329-334 (1979)
[14] Park, W. J., An optimal design of simple symmetric laminates under the first ply failure criterion, J. Composite Mat., 16, 341-355 (1982)
[15] Tauchert, T. R.; Adibhatla, S., Design of laminated plates for maximum stiffness, J. Composite Mat., 18, 58-69 (1984)
[16] Tsai, S. W.; Hahn, H. T., Introduction to Composite Materials (1980), Technomic: Technomic Westport, CT
[17] Yiping, C., Optimal design of a laminate containing an elliptical hole, Mech. Res. Comm., 11, 329-336 (1984)
[18] Jones, R. M., Mechanics of Composite Materials (1975), Scripta Book Company: Scripta Book Company Washington, DC
[19] Bauchau, O. A., Optimal design of high speed rotating graphite/epoxy shafts, J. Composite Mat., 17, 171-180 (1983)
[20] Chung, K. Y., Shape optimization and free boundary problems with grid adaptation, (Ph.D. Dissertation (1986), University of Michigan: University of Michigan Ann Arbor, MI)
[21] Soni, S. R., Failure analysis of composite laminates with a fastener hole, ASTM STP 593, 145-164 (1981)
[22] Krauthammer, T., Accuracy of finite element method near a curved boundary, Comput. & Structures, 10, 921-929 (1979) · Zbl 0421.73073
[23] Nuismer, R. J.; Whitney, J. M., Uniaxial failure of composite laminates containing stress concentrations, ASTM STP 593, 117-142 (1975)
[24] Lekhnitskii, S. G., Anisotropic Plates (1960), Gordon and Breach: Gordon and Breach New York · Zbl 0104.19101
[25] M. Hyer, Private Communication.; M. Hyer, Private Communication.
[26] Kikuchi, N., Finite Element Methods in Mechanics (1986), Cambridge University Press: Cambridge University Press New York · Zbl 0587.73102
[27] Lee, M. S., Shape optimization of a hole in symmetric laminates, (Ph.D. Dissertation (1987), University of Michigan: University of Michigan Ann Arbor, MI)
[28] Bäcklund, J.; Isby, R., Shape optimization of holes in composite shear panels, (Proceedings IUTAM Symposium on Structural Optimization. Proceedings IUTAM Symposium on Structural Optimization, Melbourne, Australia (1988))
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.