可以采用 link10 (单向受力单元)单元,将单元性质设置为只承受拉力。我试了一下,对第一种载荷条件,最大垂度为 1.46 m,误差约3.5%。但对第二种载荷情况最大垂度达 1.717 m,似乎误差太大了一些,尚未找到问题何在。命令流附后,仅供参考。
同时说明一下,采用 link10 单元,打开大变形选项即可,单元常数只需截面积,其它常数则用不着。
fini
/clear,start
!
/PREP7
k,1
k,2,4
k,3,8
k,4,12
k,5,16
!*
l,1,2
l,2,3
l,3,4
l,4,5
!*
ET,1,LINK10
!*
KEYOPT,1,2,0
KEYOPT,1,3,0
!*
!*
R,1,0.001, ,
!*
MPTEMP,,,,,,,,
MPTEMP,1,0
MPDATA,EX,1,,1.8e11
MPDATA,PRXY,1,0.3,
!*
LATT,1,1,1, , , ,
!*
LESIZE,ALL, , ,1, ,1, , ,1,
LMESH,all
!*
FINISH
/SOLU
!*
ANTYPE,0
!*
DK,3, , , ,0,UX, , , , , ,
DK,1, , , ,0,UY,UZ, , , , ,
DK,5, , , ,0,UY,UZ, , , , ,
!*
!*
FK,1,FX,-85150
FK,5,FX,85150
!*
FINISH
/SOLU
!*
NLGEOM,1
!*
FLST,2,3,3,ORDE,2
FITEM,2,2
FITEM,2,-4
/GO
FK,P51X,FY,-16000
!*
LSWRITE,1,
!*
FK,2,FY,-20000
FK,3,FY,-20000
FK,4,FY,-16000
!*
LSWRITE,2,
!*
ANTYPE,0
LSSOLVE,1,2,1,
!* |