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Treatment of Model Uncertainties in Structural Dynamics


Katafygiotis, Lambros Solon (1991) Treatment of Model Uncertainties in Structural Dynamics. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/6s88-dn31.


The uncertainties related to the modeling of the dynamic behavior of a structure are analyzed using a probabilistic approach.

First, the case of preliminary design is addressed, where the structure has not yet been built. A new efficient and accurate numerical method is proposed to investigate the resulting uncertainties in the structural response due to uncertainties in the modeling process, where engineering judgement is used to quantify the latter uncertainties.

Second, the case where records of measured structural response are available to reduce the uncertainties in the structural models is addressed. The posterior probability distribution of the uncertain parameters is found to be very peaked at the values of some optimal parameters. These optimal parameters can be obtained by minimizing a positive-definite measure-of-fit function. A new efficient minimization algorithm is proposed to resolve difficulties in convergence of existing methods. The identifiability of the optimal parameters is also addressed. The problem of finding the whole set of the optimal models that have the same output at the observed degrees of freedom is resolved for the first time, by presenting an algorithm which methodically and efficiently searches the parameter space.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:Civil Engineering
Degree Grantor:California Institute of Technology
Division:Engineering and Applied Science
Major Option:Civil Engineering
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Beck, James L.
Group:Earthquake Engineering Research Laboratory
Thesis Committee:
  • Unknown, Unknown
Defense Date:1 May 1991
Other Numbering System:
Other Numbering System NameOther Numbering System ID
EERL Report91-01
Record Number:CaltechTHESIS:04252011-102457629
Persistent URL:
Related URLs:
URLURL TypeDescription ItemTechnical Report EERL 91-01 in CaltechAUTHORS
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:6349
Deposited On:25 Apr 2011 17:41
Last Modified:20 Aug 2021 22:59

Thesis Files

PDF (Katafygiotis_ls_1991.pdf) - Final Version
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