Modeling A
==============




Characteristics of modeling
-----------------------------------

Viscoelastic material: 3D_SI modeling.

Steel material: modeling DKT (surface elements are the lower skin of the volume elements of the viscoelastic layer).


.. image:: images/1000000000000569000002380ECADD251E1F4183.png
    :width: 4.1272in
    :height: 2.0598in


.. _RefImage_1000000000000569000002380ECADD251E1F4183.png:

steel layer

(DKT)

viscoelastic layer

(3D_SI)
Image 3.1-1: Structure mesh.

steel layer

(DKT)



Characteristics of the mesh
----------------------------

Number of knots 186

Number of meshes 376

 of which: elements SEG2 132

                 QUAD4 184

                 HEXA8 60




Tested sizes and results
------------------------------

The calculation of natural modes with the option TYPE_MODE =' COMPLEXE 'makes it possible to test both natural frequencies and modal damping. Only the modes of bending in the thickness of the beam are tested (mode No. 3 is a bending in the width).


.. csv-table::

    "**Mode**", "**Natural Frequency (Hz)**", "**Tolerance**", "**Damping**", "**Tolerance**"
    "1", "33.093"," 1.0% ", "0.011782"," 12.0%"
    "2", "211.356"," 1.0% ", "0.018138"," 10.0%"
    "4", "601.643"," 2.0% ", "0.018834"," 10.0%"


**Table** 3.3-1 **: Reference values tested.**