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Mode-base steady-state analysis U=TU??

Mode-base steady-state analysis U=TU??

Mode-base steady-state analysis U=TU??

(OP)
Hello everybody:

I have been develop a mode-base steady-state analysis to find the absolute  and relative displacement in mechanical elements but i don't know why in the results the absolute and relative  response are the same.

Does any body knows what is the problem?

Here is the code!!!

*HEADING
Mode-base steady-state dynamic analysis
*NODE, NSET=GLOBAL
   1,          0.,          0.
   2,          0.333,       0.
   3,          0.666,       0.
   4,          0.999,       0.
*ELEMENT, TYPE=MASS, ELSET=P1
   1,      2
*ELEMENT, TYPE=MASS, ELSET=P2
   2,      3
*ELEMENT, TYPE=MASS, ELSET=P3
   3,      4
*ELEMENT, TYPE=SPRING2, ELSET=P4
  11,      1,2
*ELEMENT, TYPE=SPRING2, ELSET=P5
  22,      2,3
*ELEMENT, TYPE=SPRING2, ELSET=P6
  33,      3,4
*MASS, ELSET=P1
        2
*MASS, ELSET=P2
        2
*MASS, ELSET=P3
        2
*SPRING, ELSET=P4
    1, 1
    1
*SPRING, ELSET=P5
    1, 1
    1
*SPRING, ELSET=P6
    1, 1
    1
*NSET, NSET=FIX
    1
****************************************************
*AMPLITUDE, DEFINITION=PERIODIC, NAME=fn_senoidal_BASE
**rad/time(s)
1, 4.3, 0, 0
**amplitude
0, 0.005
****************************************************
*STEP
*FREQUENCY, eigensolver=Lanczos
5, ,
*BOUNDARY, TYPE=DISPLACEMENT
FIX,ENCASTRE
*BOUNDARY
GLOBAL, 2,3
*EL PRINT, SUMMARY=NO,  MODE=1, LAST MODE=5
*NODE PRINT, SUMMARY=NO, MODE=1, LAST MODE=5
U
*OUTPUT, FIELD, MODE LIST
1, 2, 3, 4, 5
*NODE OUTPUT
U
*END STEP
*****************************************************
*STEP,NLGEOM=NO, NAME= steady state dynamics
*STEADY STATE DYNAMICS, FREQUENCY SCALE=LINEAR, INTERVAL=EIGENFREQUENCY
0, 0.5, 10,3
*SELECT EIGENMODES, GENERATE
1,5,1
*MODAL DAMPING, MODAL=DIRECT
1,5, 0.02
*BASE MOTION, DOF=1, LOAD CASE=2, AMPLITUDE=fn_senoidal_BASE
*NODE PRINT,FREQUENCY=1
U,TU,TV
V,A
*NODE FILE,NSET=GLOBAL
U,V,A,TU,TV
*MODAL FILE
GU,GV,GA
*OUTPUT,FIELD, OP=NEW, FREQUENCY=1
*NODE OUTPUT,NSET=GLOBAL
U,V,A,TU,TV
*OUTPUT,HISTORY,OP=NEW, FREQUENCY=1
*NODE OUTPUT,NSET=GLOBAL
U,V,A,TU,TV
*MODAL OUTPUT
GU,GV,GA
*END STEP

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