1. Finite element techniques, although widely applied to structural mechanics problems, have been applied very few times 2g-32 to the problem of large deflection random response. Hwang and Pizg were apparently the first researchers to consider uslng a f i n i t e element approach for large deflection random vibration of plates, but their proposed method was found t o he inapplicable for acoustic pressure levels that were too high. Recently, Chiang and )lei 3' considered a multiple-mode solution for the large deflection random response o f beams. Their results were found to compare very well with results obtained using a classical approach, thus establishing the applicability of the finite elelnent inethod t o the problem of nonlinear random vibration. The oovernino nonlinear eauations of motinn for the ;resent Gtudy are deri'ved using the principle of virtual work. Special care i s taken to ensure that the f i r s t - and second-order nonlinear stiffness matrices are symmetric. For the thermal postbuckling analysis, the inethod of Newton-Raphson iteration i s used to determine the deflections and stresses due to temperature only. These deflections and stresses are then used as i n i t i a l deflections and stresses for the randoin vibration analysis.
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3. Figures 1-5 illustrate the comparison o f the results Obtained -_using 36 elements to Paul's classical results" for the case of a uniform , temperature distribution. The deflection results
4. and the Center stress results (Figs. 2 and 3) are very nearly identical with Paul's solution, and the edge stresses (Figs. 4 and 5) are w r v close. For t.hr rase o f a nominiformi temperature distribution (AT (x,y) = To (1 - cos 2nx 7) (1 - cos $)), the results are shown i n 0 Figs. 6-10. As for the case of a uniform temperature distribution, the center deflections and stresses compare more favorably, and the edge