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$$$$ DECONV   NOTICE  AF221230  13/12/12    21:15:00     7881           
                                             DATE     13/12/12

    procedure DECONV                          Voir aussi : DECONV3D
    ----------------   
   TABRESU =  DECONV COUCHE FOND_SOL MOD_SOL (SOL) DIR
                     GAMMAO F1 F2 (FC) (TYP_F) (P_GAMMA)



Description :
-------------

This procedure allows the user to perform 2D (plane strain or FOURIER
mode 0 (vertical motion) and 1 (horizontal motion) soil-structure
interaction (SSI) analysis by modelling the soil and the
structure with finite elements. It has two functions :
  - formulate the damping matrix corresponding to the viscous
    absorbing boundary representing the far field soil not included
    in the soil mesh,
  - calculate the seismic loading to be applied on the soil boundary
    by the deconvolution of the control motion given on the free
    surface of the soil.
The resolution of the problem can be conducted afterwards in the time
domain using one of the following integration procedures :
  - Procedure DYNAMIC for linear material behaviour, possibility to
    include unilateral contacts to model the uplift and the sliding
    of the foundation,
  - procedure PASAPAS in case of non linearities of the soil and the
    structure (plane strain only).

Comments :
----------

Input data :
-----------

COUCHE :  double-indexed TABLE containing the soil properties :

  COUCHE.I : SOUS-TABLE relative to the ith layer of the soil
             which contains the following indices :

 'FRONTIERE'       : MAILLAGE, vertical boundary of the ith layer
 'MASSE_VOLUMIQUE' : FLOTTANT, density
 'POISSON'         : FLOTTANT, Poisson's ratio
 'YOUNG   '        : FLOTTANT, Young's modulus
 'AMORTISSEMENT    : FLOTTANT, damping ratio

FOND_SOL : MAILLAGE,  lower horizontal boundary of the soil mesh
MOD_SOL  : MMODEL,    physical model of the soil
SOL      : MAILLAGE,  soil mesh (QUA8 or TRI6), optional
DIR      : MOT,       direction of the free field acceleration
                      'HORI' for the horizontal direction (SV wave)
                      'VERT' for the vertical direction (P wave)
GAMMAO   : EVOLUTION, free field horizontal acceleration on
                      the surface. The beginning of this
                      accelerogram must contain a time interval
                      with null acceleration (at least 100 time steps).
                      It is the time that allows the wave front to go
                      upwards through the ground which is represented
                      by the soil mesh.
F1, F2   : FLOTTANTS, frequencies on which the damping ratio
                      is adjusted according to Rayleigh model.
FC       : FLOTTANT,  cutting frequency for the deconvolution
                      by default  FC = 50 Hz
TYP_F    : MOT,       type of boundary : 'WHITE' (by default)
                                         'LYSMER'
P_GAMMA  : TABLE containing the input and output accelerations for the  (not nec

       'ENTREE'           :TABLE,     type of acceleration (different from free 
               'NATURE'      : Nature of controle point:
                              'MOT' PROFOND : inside (depper on the soil)
                              'MOT' OUTCROP : outcrop of bedrock
               'CONTROLE'    :'MAILLAGE',   controle point on the bondary mesh
                                            (necessary if 'NATURE' = PROFOND)
                     'I'     :'MAILLAGE', I-point (i = 1, 2, 3,...) on the verti
                                          where we plot the accelerations
Output data :
-------------


TABRESU  : TABLE which contains the computation results

  indice 'CHAR'  : CHARGEMENT, seismic excitation on the soil boundary
  indice 'AMOR'  : RIGIDITE,   damping matrix of the TYP_F type
                               absorbing boundary
  indice 'DEFO'  : EVOLUTION,  maximum soil strain as a function of
                               depth
  indice 'ACCE'  : TABLE,      table which contains the accelerograms
                               of the points defined in P_GAMMA
  indice 'PAS'   : FLOTTANT
  indice 'FCDYN' : FLOTTANT,   time step and cutting frequency to be
                               used in the analysis of soil-structure
                               interaction with DYNAMIC or PASAPAS
                               procedure

Note :
--------

The procedure does not work with oblique boundaries. It deals with
horizontal (SV wave) and vertical (P wave) seismic motions.

The procedure is elaborated to perform the deconvolution on half
the boundary. If the mesh is symmetrical or axisymmetrical, just
call on the DECONV procedure once.

If the mesh (soil + structure) is not symmetrical, it will have to
be split into two halves from the OY-axis. The DECONV procedure is
called on twice to perform the deconvolution of both mesh halves.

$$$$


 
 
 

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