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

[Alejandre]

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