1. But

POST_DYNA_ALEA allows you to perform two types of post-processing after a stochastic dynamics calculation:

Calculation of fragility curves from a table containing the results of a Monte Carlo simulation

From a table [table_sdaster] containing information on the levels of excitation (in seismic analysis, PGA is generally chosen) and the variable of interest characterizing the failure or not of the structure, POST_DYNA_ALEA makes it possible to determine the parameters of a fragility curve according to the lognormal model and to calculate the values of this curve. The reader can consult [U2.08.05] for a more detailed description.

Statistically post-processing of cross-spectrum results.

POST_DYNA_ALEA makes it possible to calculate statistical parameters on functions selected in an [interspectrum] concept: spectral moments, standard deviation, peak distribution, central frequency.

The interspectral matrix can be obtained by various operators: read_inte_spec [U4.36.01], calc_inte_spec [U4.36.03], defi_inte_spec [U4.36.02], dyna_alea_modal [U4.53.22], DYNA_SPEC_MODAL [], [U4.53.23], or REST_SPEC_PHYS [U4.63.22]. Refer to [R7.10.01] for the description of the treatments performed.

This operator produces a table_sdaster table that can be printed by IMPR_TABLE [U4.91.03].