Load Control

• Command_Manual
  • Tcl Commands
  • Modeling_Commands
    • model
    • uniaxialMaterial
    • ndMaterial
    • frictionModel
    • section
    • geometricTransf
    • element
    • node
    • sp commands
      • fix
      • fixX
      • fixY
      • fixZ
    • mp commands
      • equalDOF
      • rigidDiaphragm
      • rigidLink
    • timeSeries
    • pattern
    • mass
    • block commands
      • block2D
      • block3D
    • region
    • rayleigh
  • Analysis Commands
    • constraints Command
    • numberer Command
    • system Command
    • test Command
    • algorithm Command
    • integrator Command
    • analysis Command
    • eigen Command
    • analyze Command
  • Output Commands
    • recorder
    • record
    • print
    • printA
    • logFile
    • RealTime_Output_Commands
  • Misc Commands
    • eleResponse Command
    • getTime Command
    • getEleTags Command
    • getNodeTags
    • loadConst Command
    • nodeCoord Command
    • nodeDisp Command
    • nodeVel Command
    • nodeAccel Command
    • nodeEigenvector Command
    • nodeBounds
    • print Command
    • remove Command
    • reset Command
    • testIter
    • testNorms
    • wipe Command
    • exit Command
  • DataBase Commands
    • Template:DataBaseCommandsMenu

---

This command is used to construct a Newmark integrator object.

integrator LoadControl $lambda <$numIter $minLambda $maxLambda>

---

$lambda	<math>\lambda</math> factor
$numIter	the number of iterations the user would like to occur in the solution algorithm. Optional, default = 1.0.
$minLambda	the min stepsize the user will allow. optional, defualt = <math>\lambda_{min} = \lambda</math>
$maxLambda	the max stepsize the user will allow. optional, default = <math>\lambda_{max} = \lambda</math>

---

NOTES:

1. The change in applied loads that this causes depends on the active load patterns (those load patterns not set constant) and the loads in the load patterns. If the only active loads acting on the domain are in load patterns with a Linear time series with a factor of 1.0, this integrator is the same as the classical load control method.
2. The optional arguments are supplied to speed up the step size in cases where convergence is too fast and slow down the step size in cases where convergence is too slow.

---

EXAMPLE:

integrator LoadControl 0.1;

---

THEORY:

In Load Control the time in the domain is set to <math>t + \lambda_{t+1}</math> where,

<math> \lambda_{t+1} = \max \left ( \lambda_{min}, \min \left ( \lambda_{max}, \frac{\text{numIter}}{\text{lastNumIter}} \lambda_{t} \right ) \right ) </math>

---

Code Developed by: fmk