模拟挡土墙，shell63和combin14连接问题

求各位高手解答小弟心中疑问。。这个问题是否涉及自由度问题？该怎么处理就可以计算了？命令流中数据仅供参考

finish
/title,dangtuqiang
/clear
/prep7
Et,1,shell63
et,2,combin14
keyopt,2,3,2
Mp,ex,1,3e4
Mp,prxy,1,0.3
Mp,dens,1,26e-7
r,1,250!挡土墙厚
r,2,350!基础厚度
r,3,2e7
b2=625!基础半宽
h=3600!挡土墙高
k,1,-1500,-425
k,2,-1500
k,3,1500
k,4,1500,4000
l,1,2$l,2,3$l,3,4
k,5,1500,,h$l,3,5
/pnum,line,1
adrag,1,2,3,,,,4
lgen,2,1,3,2,-b2
lgen,2,1,3,2,b2
lgen,2,2,,,,-b2
lgen,2,2,,,,b2
lextnd,16,19,b2
lextnd,15,16,b2
lextnd,13,12,b2
numcmp,all$nummrg,all
lovlap,all
a,13,17,16,12
a,20,19,12,18
aadd,4,5
/pnum,kp,1$/pnum,area,1
aovlap,all
wpoffs,,-425
wprota,,90$asbw,all
asel,all
lsla
lsel,inve
ldele,all
allsel,all
asel,s,loc,z,0
aatt,1,2,1
asel,inve
aatt,1,1,1
allsel,all
lesize,all,100
mshape,0$mshkey,0$amesh,all
nsel,s,loc,z,0
ngen,2,10000,all,,,,,-500
!asel,s,loc,z,0
!nsla
!ngen,2,30000,all
type,2$real,3

*get,nno,node,0,count
*get,nnomin,node,0,num,min
*do,i,1,nno/2
*get,nnonext1,node,nnomin,nxth
e,nnomin,nnomin+10000
nnomin=nnonext1
*enddo


nsel,s,loc,z,-500
d,all,all,0

allsel
!cmsel,s,noorg,node
asel,s,loc,z,0

da,all,ux,0
da,all,uy,0


allsel,all

/solu
!加载
asel,s,loc,z,100,3000
sfa,all,2,pres,0.01
/solu$solve