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This macro-command allows a fast and efficient post-processing calculation to determine the floor spectra of any building after a dynamic seismic analysis taking into account the interaction of the floor with the masses of the equipment (cf. documentation [R4.05.08]).

For example, it can be used after a transient dynamic calculation of a building during the earthquake, transient dynamic calculation on a reduced modal basis, calculated as a relative coordinate system, or even after a non-linear transient dynamic resolution.

This macro-command executes in succession:

1. extracting the relative acceleration at one or more nodes of the mesh in the result concept (RECU_FONCTION [U4.32.03]);

2. the combination with ground acceleration to obtain absolute acceleration (CALC_FONCTION [U4.32.04]);

3. calculation of the transfer function that takes into account the interaction of the floor and the masses

4. calculating the acceleration response spectrum with several damping coefficients (CALC_FONCTION [U4.32.04]);

5. Impression of floor spectra.

For practical examples of implementation, the reader can refer to the sdld109 test case [V2.01.109].

The macro command produces a table_sdaster concept.