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Dynamics (natural frequencies) - surfaces (esas.22)

esas.22

Eigen frequencies can be required to verify comfort criteria for buildings, to analyze wind-induced resonance for bridges, to check requirements for sensitive equipment.... The esas.22 module enables you to apply this analysis type to structures containing surface elements (plates and shells) by performing a few steps:

- Input of dynamic masses
- Selection of desired number of characteristic values
- Review of numerical and graphical results: frequency values, mass participation factors and modal shapes

Highlights |
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Calculation of the characteristic frequencies and modes of the member construction. |

Automatic calculation of the self-weight of the structure. |

Other weights can be entered as local or distributed loads or converted from earlier static calculations into dynamic weight. |

The user sets the desired number of characteristic values. |

For each characteristic value, the characteristic mode will be calculated with the subspace iteration method. |

The results can be represented both numerically and graphically. |

### Input of masses

- User input of nodal masses, linear distributed masses or surface masses
- Automatic generation of masses from the self-weight
- Generation of masses from selected static load cases (converts downward vertical loads into masses)
- Regeneration of masses after modification of selected load cases

### Output of results

- Table output of eigen frequencies for each calculated natural mode
- Table output of mass participation factors according to each global direction (X, Y and Z).
- Graphical display of animated eigenmode shapes

23/07/2014