索撑网壳，总是在0.2S左右提示不收敛，是模型原因么？

finish
/clear
/prep7
*afun,deg
!(1)用户界面设计，输入基本几何参数
f=16
a=80
f1=8
f2=8
!(2)计算节点坐标位置，并定义节点
N1=35
ARC=4*Atn(2*f1/a)
R=a/(2*sin(ARC/2))
DFJ=ARC/N1
DFYC=R*sin(DFJ/2)*2
*do,i,1,N1+1
*do,j,1,N1+1
x=a-sin((ARC-DFJ*(i-1))/2)*R*2*cos((DFJ*(i-1))/2)
y=a-sin((ARC-DFJ*(j-1))/2)*R*2*cos((DFJ*(j-1))/2)
z=sin((ARC-DFJ*(i-1))/2)*R*2*sin((DFJ*(i-1))/2)+sin((ARC-DFJ*(j-1))/2)*R*2*sin((DFJ*(j-1))/2)
N,N1*(i-1)+j,x,y,z
*enddo
*enddo
ndele,(N1+1)*N1+1
!(3)定义单元类型及实常数
et,1,beam4
et,2,link10
mp,ex,1,2.06e11
mp,dens,1,7850
mp,alpx,1,1.2e-5
mp,prxy,1,0.3
tb,biso,1,1,2,
tbtemp,0
tbdata,,235e6,0,,,,
mp,ex,2,1.3e11
mp,dens,2,7850
mp,alpx,2,1.2e-5
mp,prxy,2,0.3
tb,biso,2,1,2
tbtemp,0
tbdata,,1300e6,0,,,,
!定义单元实常数
E=1.3e11
r,1,4.808e-4,20.496e-8,6.794e-8,60e-3,40e-3
r,2,30.4e-6,4.466000750E-04
!(4)定义单元连接
type,1
mat,1
real,1
*do,i,1,N1+1
*do,j,N1*(i-1)+1,N1*(i-1)+(N1-1)
e,j,j+1
*enddo
*enddo
type,1
mat,1
real,1
*do,i,1,N1*N1
e,i,i+N1
*enddo
type,2
mat,2
real,2
*do,i,1,N1
*do,j,N1*(i-1)+1,N1*(i-1)+(N1-1)
e,j,j+N1+1
*enddo
*enddo
type,2
mat,2
real,2
*do,i,1,N1
*do,j,N1*(i-1)+2,N1*(i-1)+N1
e,j,j+N1-1
*enddo
*enddo
!(5)施加约束
d,1,all,0,,N1
d,1,all,0,,N1*N1+1,N1
d,N1,all,0,,(N1+1)*N1,N1
d,N1*N1+1,all,0,,(N1+1)*N1
finish
save,gridshell,db,,all

/config,nres,2000
/solu
antype,0
pstres,on
eqslv,spar
*use,dead_load.mac,2.0
*use,snow_load.mac,2.0
acel,0,0,9.8*2.0
nsubst,10,100,10
solve
finish

/solu
antype,1
bucopt,lanb,1
mxpand,1
solve
finish

/prep7
upgeom,0.27,last,last,'gridshell','rst',' '
finish

/solu
fcum,add
*do,i,1,3,1
*use,dead_load.mac
*use,snow_load.mac
*enddo

antype,0
nlgeom,1
outres,all,all
arclen,1,0,1/1000,
arctrm,u,1,,uz
nsubst,100
solve
finish

/post26
nsol,2,593,u,z,deflection
prod,4,2,,,,,,-1,1,1,
prod,5,1,,,,,,3,1,1,
/axlab,x,deflection(m)
/axlab,y,load(kn/m2)
xvar,4
plvar,5