The paper deals with a new mixed finite element method of solution of the bending problem of clamped anisotropic/orthotropic/isotropic plates with variable/constant thickness. This new mixed method gives simultaneous approximations to displacement u and bending and twisting moment :ensor ($*J, i, jp 2. Computer implcmentttion procedures for this mixed method are given along with results of numerical experiments on a good number or interesting problems. bent anisotropic plate such that (PI: Au =fin a ulr = (i?u/r3n)(, = 0 where thc anisotropic plate operator A is defined by (in (2) and ulso in the sequel, the Einstein's summation convention with respect 10 twice repeated indices i, j , k, 1 = I , 2, is to be understood), aijkt = aijkl(x 1, x2) V (x , x2 j c Tz = n u r are anisotropic platc coeficients3 satisfying the following conditions: Vi,J k, I = 1,2, a i j k l E C"(a); rzijk,(x) =a#.,ij(x) = aklji(x) alkji(x)b x = ( X I , X 2 ) E a (33 and explicitly given in the notations of References 15 and 23 as foilows: uiiii=Dii(i= 1,2); a1212=a1221 = n 2 1 1 2 = u 2 1 2 1 = D S 6 ; u1122 = a 2 2 1 1 = D I 2 (4 Dij=Dij(xl,x2)tl(x,,x2)~~denoterigiditics15defined byDij= Ri,it3/12(i= 1,2j= I, 2,6), the Bi,:s being expressions in terms of elastic constants of the generalized Hooke's law for the anisotropic material of the thin plate given in Reference 15, r .t ( x l , x 2 ) being the thickness of the plate at the point ( x , , x2)€fi, such that =a121l = a I l l 2 = ~l l t l = a 2 ] l l =DIG; a1222=02322 = ~2 2 1 2 = u2221 = DM D11, Dtt, D66 > 0 , D 1 2 =~1 1~2~= v 2 D 1 1 (OG vi < 1/2), O < Di6 < (1 -~j ) D , i (i # j ) 1 < i,j < 2, D,,+Djzc, < D66 (5) CL4MPED ANISOTROPIC PLATE BFNDING PROBLEMS