SOLUTION
  title 'modal random vibration run of a test fixture model'
  case eigen
    eigen
      nmodes 20
      # default value, works for most structure.
      # For structures with very high or low modes
      # should be set equal to the negative of the
      # first expected eigenvalue
      shift -1e6
  case modalranvib
    # Compute modal random vibration solution, keeping all modes.
    # lfcutoff removes all modes below the specified frequency.
    # There should be no modes with significantly negative frequency
    # values thus the -10 will keep all modes.
    modalranvib
    lfcutoff -10  
END

PARAMETERS
 # Conversion between mass and weight
 wtmass=0.00259008
END

FILE
   geometry_file 'fixture.exo'
END

LOADS
END

FREQUENCY
  nodeset 1,270
  acceleration
  freq_min 100
  freq_max 8000
  freq_step 200
END

DAMPING
  # Uniform model damping over all mode, as percentage
  # of critical damping
  gamma 0.02
END

// scale = concentrated mass * wtmass
RANLOADS
  # This defines three simultaneous random loads acting on the
  # X, Y, and Z directions on a single node
  matrix 1
  load 1
    nodeset 1
    force 1.0 0.0 0.0
    scale 2.59e+4
  load 2
    nodeset 1
    force 0.0 1.0 0.0
    scale 2.59e+4
  load 3
    nodeset 1
    force 0.0 0.0 1.0
    scale 2.59e+4
END

MATRIX-FUNCTION 1
  # This is the 'cross-power-spectral density matrix defining
  # load levels.
  # This matrix defines three independent uncorrelated modes.
  # If the load functions should be correlated the diagonal
  # terms are defined.
  name 'Power Spectral Density input'
  symmetry Hermitian
  dimension 3x3
  data 1,1
    real function 1
  data 2,2
    real function 1
  data 3,3
    real function 1
END

FUNCTION 1
  # Frequency domain force inputs, typically defined in pounds^2/Hz.
  Name = "Power_Spectral_Density"
  type = linear
  data 100.0   0.
  data 300.0   0.001
  data 500.0   0.01
  data 700.0   0.1
  data 7500.0  0.1
  data 7700.0  0.01
  data 7900.0   0.001
  data 8100.0   0.
END

OUTPUTS
  # Output will be the 'root-mean-squared' displacement and
  # acceleration and the 'root-mean-squared' con mises
  # stress
  displacement
  acceleration
  vrms
END

ECHO
  # Output per-block mass in ".rslt" file
  mass block
END

//  Block and material input

BLOCK 1
   // fixture
   material 1
END

BLOCK 2
  # Set of rigid links
  rbar
END

BLOCK 3
  # Concentrated mass and inertia on all nodes
  ConMass
  Mass 1.0e7
  Ixx  1.0e8
  Iyy  1.0e8
  Izz  1.0e8
  Offset= 0.0 0.0 0.0
END

MATERIAL 1
  # fixture - Titanium
  density=0.16   # Density in lbs/in^3 due to wtmass
                 # being used
  E=1.6e+07      # Young's modulus 
   nu=0.3         # Poisson's ratio
END

GDSW
  # Moderately tighter solver tolerance than default
  solver_tol=1e-8
END