Type

Conference Proceedings

Authors

Brian J. Walsh
Eugene J. O'Brien
Arturo González
Jason Dowling

Subjects

Mathematics

Topics
statistical distributions standard deviation finite element model cross entropy bridge weigh in motion theoretical model cross entropy method finite element updating

Finite Element Model Updating Using Cross-Entrophy (2010)

Abstract This paper presents the potential of the cross-entropy method to surmise the propertiesof a simply supported beam using as input the response of the structure to a movingload. The beam model is discretised into a number of elementary beams with assumedinitial statistical distributions of stiffness. Then, an optimisation procedure based oncross-entropy is employed to minimise differences between simulated measurementsand the results of the theoretical finite element beam model. The procedure consists ofgenerating a large sample of stiffness distributions for each elementary beam, andselecting those fitting the measured response best. Then, the parameters of thestatistical distribution of stiffness assumed for each elementary beam (mean andstandard deviation) are updated using the stiffness values of those combinations ofelementary beams giving a best solution. It is an iterative procedure where the meanvalue of each distribution tends towards the true stiffness in successive iterations. Thelevel of accuracy is limited by the quantity and quality of the available measurements.Therefore, the standard deviation of the final stiffness for each beam element (oncefurther iterations do not lead to a reduction of the error) provides an estimation of thereliability of the prediction. Here, the method is demonstrated for the characterisationof the stiffness distribution of a beam from the simulated response to a moving load.First, deflections are calculated using a finite element beam model with assumedinitial stiffness properties. There will be a record of simulated responses permeasurement point that cross-entropy will try to imitate by adjusting and improvingestimations of stiffness in successive iterations. The results show cross-entropy can beused as a valuable tool to estimate structural parameters and it has huge scope forapplications in model calibration, bridge weigh-in-motion and monitoring.
Collections Ireland -> University College Dublin -> Civil Engineering Research Collection
Ireland -> University College Dublin -> College of Engineering & Architecture
Ireland -> University College Dublin -> School of Civil Engineering

Full list of authors on original publication

Brian J. Walsh, Eugene J. O'Brien, Arturo González, Jason Dowling

Experts in our system

1
Eugene J. O'Brien
University College Dublin
Total Publications: 192
 
2
Arturo González
University College Dublin
Total Publications: 106