ABAQUS : Effect of Pre-load on Random Response Analysis
ABAQUS : Effect of Pre-load on Random Response Analysis
(OP)
I am running a random response analysis on a structure which has a static load applied prior to *Frequency and *Random response analysis.
What affect, if any does the preload have on the streses obtained in the Random Response analysis step?
As preload stresses are measured in MPa but the "Maximum stress" output (S) of the Random Response analysis step is in MPa^2/Hz.
Any ideas?
What affect, if any does the preload have on the streses obtained in the Random Response analysis step?
As preload stresses are measured in MPa but the "Maximum stress" output (S) of the Random Response analysis step is in MPa^2/Hz.
Any ideas?





RE: ABAQUS : Effect of Pre-load on Random Response Analysis
Note that the total stress will be affected, obviously.
Cheers
Greg Locock
RE: ABAQUS : Effect of Pre-load on Random Response Analysis
In a linear random analysis, you can add the static load stress to the mean value stress calculated by random analysis. To a nonlinear random analysis, the frequency response approach is unusable.
RE: ABAQUS : Effect of Pre-load on Random Response Analysis
Reported stresses are perturbation stresses about the base state (hence do not include the actual stresses which are in the base state).
As ilianhui implies, adding these (inherently linear) random stresses to the (potentially nonlinear) general stresses may result in errant answers.
I hope this makes sense.
Brad
RE: ABAQUS : Effect of Pre-load on Random Response Analysis