594
16 Computer Programs in Vibration Analysis
Table 16.9 (continued)
c
nod
global number of nodes of the element
c
rgd
rigidity matrix
c
asat
part of the element stiffness matrix
c
stiff
element stiffness matrix in global coordinates
c
gstif
overall stiffness matrix
c
amaso
overall mass matrix
c
elmas
element mass matrix
c
xg
s-coordinate of the element
c
yg
y-coordinate of the element
c
zx
normalised x-coordinate
c
zy
normalised y-coordinate
c
rho
mass density of the material
c**************************************************************************
c
nrqd
no. of eigenvalue required
c**************************************************************************
open (7,file='isofreein')
open (8,file='isofreeout')
100
format (2x, 6g13.6)
101
format(16i5)
c***************************************************************************
c
input data file and their out starts
c****************************************************************************
105
read (7,*) a,b,phai,rho,t
read (7,*) nx,ny,nn,nfree,nt,nbh,nq,nrqd
read(7,*) nbon1,nbon2,nbon3,nbon4,nsymx,nsymy
read (7,*) dx,dy,d1,dxy,sx,sy,pr
nenp=nn*nfree
nelm=nx*ny
c***************************************************************************
c***************************************************************************
write (8,*) 'FREE VIBRATION ANALYSIS OF ORTHOTROPIC PLATES'
write (8,*) 'USING ISOPARAMETRIC QUADRATIC BENDING ELEMENT'
write (8,*) '
A
B
PHAI
RHO
THICK'
write (8,100) a,b,phai,rho,t
write (8,*) ' nx
ny
nn
nfree nt
nbh nq
nelm nenp
*
nrqd '
write (8,101) nx,ny,nn,nfree,nt,nbh,nq,nelm,nenp,nrqd
write (8,*)'nbon1 nbon2 nbon3 nbon4 nsymx nsymy'
write (8,101) nbon1,nbon2,nbon3,nbon4,nsymx,nsymy
write (8,*) '
dx
dy
d1
dxy
sx
sy'
write (8,100) dx,dy,d1,dxy,sx,sy
c****************************************************************************
c****************************************************************************
c
output of the given data over
c****************************************************************************
nt= nfree*(((nn/2-1)*nx+nn/4)*ny+(nn/4)*nx+1)
nbh= nfree*((nn/2-1)*nx+(nn/2+1))
ntot= nbh*nt-nbh*(nbh-1)/2
phai= 3.1415927*phai/90.0
c****************************************************************************
c
automatic mesh generation starts
c****************************************************************************
c****************************************************************************
nx21=2*nx+1
nx1=nx+1
do 10 ii=1,nelm
nxi=(ii-1)/nx
do 14 i=1,3
14
nod(ii,i) = nx21*nxi+nx1*nxi+2*(ii-nx*nxi)+i-2
nod(ii,4) = nx21*(nxi+1)+nx1*nxi+(ii-nx*nxi)+1
nod(ii,8) =nod(ii,4) - 1
do 15 i=5,7
(continued)