为什么BEAM44单元求解后没有切应力啊？？？？

FINISH

/CLEAR

/FILNAM,YINGXIANGXIAN1

/TITLE,QI_CHE_HE_ZAI

/PREP7

!!!单位KN,M

ET,1,BEAM44
!选择BEAM44单元

MP,EX,1,2.06E8
!定义材料特性

MP,PRXY,1,0.3

MP,DENS,1,7.85

!beam44实常数1，面积
Iz
Iy
下层厚度  扭转惯性矩  形心偏移

R,1,
49.91E-4,435.8E-8,7776E-8, 0.15,0.063,
0,
0,0,0 ,
0.15,0.063

N,1000,0,1,0

*DO,I,1,241

N,I,(I-1)*0.025,0,0

*END DO

TYPE,
1

MAT,
1

REAL,
1

*DO,I,1,240

E,I,I+1,1000

*END DO

/SOLU

D,NODE(0.525,0,0),UY,,,,,

D,NODE(0.975,0,0),UY,,,, ROTX, ROTZ ,UX

D,NODE(5.025,0,0),UY,,,,,,

D,NODE(5.475,0,0),UY,,,,,

ACEL,0,9.81*1.2,0

SFEDELE,ALL,1,PRES

ESEL,ALL

ESEL,S,,,43,66,1

ESEL,A,,,114,137,1

SFBEAM,ALL,1,PRES,231,231,,,,, !加载均布力231KN/M

ESEL,ALL

SOLVE