*HEADING
 FREE VIBRATION OF SPRING-DASHPOT-MASS SYSTEM  
*NODE,NSET=FILE
 1,10.
*ELEMENT,TYPE=DASHPOT1,ELSET=DASHPOT_EL
1,1
*DASHPOT,ELSET=DASHPOT_EL
 1, 
0.12, 
*ELEMENT,TYPE=SPRING1,ELSET=SPRING_EL
2,1
*SPRING,ELSET=SPRING_EL
 1, 
 30., 
*ELEMENT,TYPE=MASS,ELSET=MASS_EL
3,1
*MASS  ,ELSET=MASS_EL
0.02588, 
*STEP
  STRETCH OUT
*STATIC
1.E10,1.E10
*BOUNDARY
 1,1,1,1.
 1,2,3
*ENERGY PRINT,FREQUENCY=2
*ENERGY PRINT,FREQUENCY=2,ELSET=SPRING_EL
*ENERGY PRINT,FREQUENCY=2,ELSET=MASS_EL
*ENERGY PRINT,FREQUENCY=2,ELSET=DASHPOT_EL
*EL PRINT,FREQUENCY=2,SUMMARY=NO
S,E
*NODE PRINT,FREQUENCY=2,SUMMARY=NO
U1,V1,A1,CF1,RF1
*ENERGY FILE,FREQUENCY=10
*ENERGY FILE,ELSET=SPRING_EL,FREQUENCY=10
*NODE FILE,NSET=FILE
U , V , A
*END STEP
*STEP,INC=200
  RELEASE INITIALLY STRETCHED SYSTEM
*DYNAMIC,HAFTOL=1.
 5.E-4,.7,,0.7
*BOUNDARY,OP=NEW
1,2,3
*END STEP