*HEADING
 SQUARE PLATE - ELASTIC BUCKLING  ( BUCKLE )  
*NODE
101, 
105,1.
501,0.,1.
505,1.,1.
*NGEN,NSET=YSYM
101,105
*NGEN,NSET=XSYM
101,501,100
*NGEN,NSET=YEDG
501,505
*NGEN,NSET=XEDG
105,505,100
*NFILL
XSYM,XEDG,4,1
*ELEMENT,TYPE=STRI65,ELSET=ONE
    1,   101,   103,   303,   102,   203,   202
50001,   101,   303,   301,   202,   302,   201
*ELGEN,ELSET=ONE
    1,     2,     2,     1,     2,   200,     2
50001,     2,     2,     1,     2,   200,     2
*SHELL SECTION,MATERIAL=A1,ELSET=ONE
.01,3
*MATERIAL,NAME=A1
*ELASTIC
1.E8,.3
*BOUNDARY
YSYM,YSYMM
XSYM,XSYMM
YEDG,3
YEDG,5
XEDG,3
XEDG,4
XEDG,6
*STEP
*BUCKLE
3,
*CLOAD
105,1,-8.33333333
205,1,-33.3333333
305,1,-16.66666667
405,1,-33.3333333
505,1,-8.3333333
*NODE PRINT
U, 
RF, 
*MODAL FILE
*END STEP