*HEADING
 BARREL VAULT  ( 18 X 18 MESH , SC8R)  
*PREPRINT,ECHO=YES,MODEL=YES,HISTORY=NO
*NODE,SYSTEM=C,NSET=CORNER
   1,298.5,0.,0.,
  19,298.5,,300.
 361,298.5,40.,
 379,298.5,40.,300.
1001,301.5,0.,0.,
1019,301.5,,300.
1361,301.5,40.,
1379,301.5,40.,300.
*NGEN,LINE=C,NSET=WALL
    1, 361, 20
 1001,1361, 20
*NGEN,LINE=C,NSET=SYMM
   19, 379,20,,,,300.
 1019,1379,20,,,,300.
*NFILL
 WALL,SYMM,18,1
*NGEN,NSET=APEX
    1,   19
 1001, 1019
*ELEMENT,TYPE=SC8R,ELSET=ROOF1
 1, 1001, 1002, 1022, 1021, 1, 2, 22, 21
*ELGEN,ELSET=ROOF
 1,18,1,1,18,20,20
*ELSET,ELSET=FEW
 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,
 17,18
*MATERIAL,NAME=STEEL
*ELASTIC
 3.E6, 
*BOUNDARY
 APEX,YSYMM
 SYMM,ZSYMM
 WALL,1,2
*SHELL SECTION,MATERIAL=STEEL,ELSET=ROOF,POISSON=ELASTIC
 3.0,3
*STEP
 SELF-WEIGHT
*STATIC
*DLOAD
 ROOF,BX,-0.20833
*ENERGY PRINT
*EL PRINT,FREQUENCY=0
*EL FILE,ELSET=ROOF1
S, 
*NODE FILE,NSET=CORNER
U, 
RF, 
*EL FILE
*END STEP