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Papers quoted in Current Contents on project 2-11-415
Quoted papers: 3
Other papers: 3
Total: 6
Title: FATIGUE FAILURE DUE TO A RANDOM STRESS PROCESS
- Authors:
- Diklic, Dea (9682)
- Diklic, Dea (9682)
Journal: Stability of Steel Structures,Preliminary
Report,International Colloquium
Volume: II.
Year: 1995
Pages: from 369 to 376
Number of references: 1
Language: engleski
Summary: The essential characteristic of earthquake is its
irregularity,its random character.Although the time variation of the random
vibration cannot be predicted,the probability of a given value being within
a certain range is predictable on statistical basis.The problem is that the
unlimited ground-motion data in form of accelerograms are not avilable,so
the representative stochastic model couldn't be established directly by
statistical analysis.For practical purposes artificially generated process
must be simple enough,but must possess the same statistical characteristics
as a real seismic record and both of them must have the equivalent respone
spectra.From this viewpoint the exciting forces are idealised as
Gaussian,stationary and ergodic process with an ideally white spectrum of
constant density over all frequencies.The building will be designed to
resist the whole ensemble of possible time histories,which have in
statistical sense the common trait.When the excitation is a
stationary,ergodic and normal random process,the respone will be
diferent,but also of the same nature.
The engineer is able to express the mean square value of the response of
the system in terms of displacement,acceleration, stress or he can
choose by himself the suitable level of reliability for the certain
building or he can predict the fatigue life under random earthquake
excitation,while the estimation of extreme value of stress is possible and
just the estimation of risk is of a great interest for metal constructions.
The purpose of this paper is to illustrate the possibilities of theory of
random vibrations in connection with estimation of failure probability.The
variable amplitude sevice life is predicted by using an adaption of the
Palmgren-Miner damage model to find the damage caused by each stress
cycle.The cumulative total of cyclic damage is then used to predict the
expected mean time of failure.The results are plotted for diferent values
of system damping.
Keywords: Random vibrations,random stress process,fatigue failure,ideal white noise,stationary process,ergodic process
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