Issue 57

K. Benyahi et alii, Frattura ed Integrità Strutturale, 57 (2021) 195-222; DOI: 10.3221/IGF-ESIS.57.16

nonlinear function (known numerically from our nonlinear calculation), whose failure of the system is observed when    1 2 G X , X 0 .

Figure 19: Limit state 

 1 2 G X , X in 2D in the reduced centered space of the beam section (SA3).

Figure 20: Limit state function 

 1 2 G X , X in 3D of the beam section (SA3).

The calculation is carried out for mean values of the various random parameters, and where several reliability iterations have been taken into consideration to converge towards the design point. The Rackwitz-Fiessler algorithm is used to perform the reliability study, and after analysis by mechanical reliability coupling by polynomial response surfaces (MRS), the HL-RF method allowed us to obtain the coordinates from the design point, the absolute values of the direction cosines of the random variables, as well as the reliability index and the probability of failure (Tab. 4) for each transition zone of the different limit state curves of the beams sections tested. As shown in the Tab. 4, there is a very good agreement of the results of the mechano-reliability coupling using a response surface method expressed as a limit state function.

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