求教 关于beam188提取最大应力

有两个问题：
1、网格划分有个警告，怎么划分比较合理？
2、提取最大EQV的时候，最大应力出来了，而单元编号inuse为0？
求高手指点。
命令流如下：
FINI
/clear,star
!hangjia.txt
/FILENAME,hangjia !设置分析工作名称
/TITLE,hangjia !设置图形标题

/PREP7 !进去前处理器
ET,1,BEAM188 !定义单元类型
KEYOPT,1,1,0
ET,2,SHELL63



SECTYPE,1,BEAM,L !L90x6
SECDATA,0.09,0.09,0.006,0.006
SECOFFSET,USER,0,0
SECTYPE,2,BEAM,L !L75x5
SECDATA,0.075,0.075,0.005,0.005
SECOFFSET,USER,0,0


R,2,0.003 !定义实常数

MP,EX,1,2.06E11 !定义材料参数
MP,NUXY,1,0.3
MP,DENS,1,7850


k,5000,1,1000,12
k,5001,1,-1000,12
k,5002,1000,0.5,12
k,5003,-1000,0.5,12
k,5004,1,0.5,1000
k,5005,1,0.5,-1000
k,1,0,1,0
k,2,0,0,0
k,3,2,0,0
k,4,2,1,0
kgen,2,1,4,1,0,0,0.25
kgen,2,1,4,1,0,0,2.75
*do,i,0,6
kgen,2,1,4,1,0,0,2.75+i*3+0.5
kgen,2,1,4,1,0,0,2.75+i*3+3
*enddo
kgen,2,1,4,1,0,0,24
kgen,2,2,3,1,0,0,1.5
*do,i,0,6
kgen,2,2,3,1,0,0,2.75+i*3+1.75
*enddo

*do,i,1,4,3
*do,j,0,16
l,i+4*j,i+4*(j+1)
*enddo
*enddo

*do,i,0,1
l,2+i,6+i
*do,j,0,7
l,6+8*j+i,73+2*j+i
l,73+2*j+i,10+8*j+i
l,10+8*j+i,14+8*j+i
*enddo
*enddo

*do,i,0,15
*do,j,0,2
l,5+j+i*4,6+j+i*4
*enddo
*enddo

*do,j,0,7
l,73+j*2,74+j*2
*enddo

*do,i,0,1
*do,j,0,7
l,5+8*j+i*3,73+2*j+i
l,73+2*j+i,9+8*j+i*3
*enddo
*enddo

*do,j,0,7
l,6+8*j,74+2*j
l,74+2*j,10+8*j
*enddo

*do,i,0,6
a,6+i*8,7+i*8,74+i*2
a,6+i*8,74+i*2,73+i*2
a,73+i*2,74+i*2,10+i*8
a,10+i*8,74+i*2,11+i*8
a,10+i*8,11+i*8,15+i*8,14+i*8
*enddo
*do,i,7,7
a,6+i*8,7+i*8,74+i*2
a,6+i*8,74+i*2,73+i*2
a,73+i*2,74+i*2,10+i*8
a,10+i*8,74+i*2,11+i*8
*enddo

lsel,s,loc,x,0
lsel,r,loc,y,1
latt,1,,1,,5002,,1


lsel,s,loc,x,2
lsel,r,loc,y,1
latt,1,,1,,5001,,1


lsel,s,loc,x,0
lsel,r,loc,y,0
latt,1,,1,,5000,,1


lsel,s,loc,x,2
lsel,r,loc,y,0
latt,1,,1,,5003,,1


lsel,s,loc,x,0.1,1.9
*do,i,0,7
lsel,u,loc,z,0.25+3*i,1.45+3*i
*enddo
latt,1,,1,,5000,,2


lsel,s,loc,x,0.1,1.9
*do,i,0,7
lsel,u,loc,z,1.5+3*i,2.75+3*i
*enddo
latt,1,,1,,5004,,2


lsel,s,loc,y,0.1,0.9
lsel,r,loc,x,0
*do,i,0,7
lsel,u,loc,z,0.3+3*i,2.75+3*i
*enddo
latt,1,,1,,5004,,2


lsel,s,loc,y,0.1,0.9
lsel,r,loc,x,0
*do,i,0,7
lsel,u,loc,z,0.25+3*i
*enddo
latt,1,,1,,5002,,2


lsel,s,loc,y,0.1,0.9
lsel,r,loc,x,2
*do,i,0,7
lsel,u,loc,z,0.3+3*i,2.75+3*i
*enddo
latt,1,,1,,5004,,2


lsel,s,loc,y,0.1,0.9
lsel,r,loc,x,2
*do,i,0,7
lsel,u,loc,z,0.25+3*i
*enddo
latt,1,,1,,5003,,2

lsel,all
lesize,all,0.125
lmesh,all

asel,all
aatt,1,2,2
AMESH,ALL

ksel,s,loc,z,23.75
ksel,r,loc,y,0
DK,all, , , ,0,UX,UY,UZ,ROTY,ROTZ, ,

ksel,s,loc,z,0.25
ksel,r,loc,y,0
DK,all, , , ,0,UX,UY,UZ,ROTY,ROTZ, ,
ALLSEL,ALL

asel,all
asel,u,loc,z,10.5,13.5
SFA,all,,pres,980
asel,s,loc,z,10.5,13.5
SFA,all,,pres,2030
ACEL,0,9.81*1.2,0,
ALLSEL,ALL
!绘图和列表显示栅格、栅点及积分点信息
!secplot,1,1
!slist,1,1,,1,all

finish
/SOLU
ANTYPE,0
SOLVE
FINISH

/post1
/eshape,1
ALLSEL,BELOW,LINE
*GET,eno,ELEM,,count
!*GET,eno,ELEM,,num,max
*GET,INUSE,ELEM,,num,min
SMAX=0
*do,i,1,eno,1
*get,SSUM,secr,INUSE,s,EQV,max
*IF,SMAX,GE,SSUM,THEN
SMAX=SMAX
*ELSEIF,SMAX,LT,SSUM
SMAX=SSUM
*ENDIF
!*GET,INUSE,ELEM,INUSE,nxth
INUSE=elnext(INUSE)
*enddo