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dc.contributor.authorGrisso, Benjamin Lukeen_US
dc.date.accessioned2014-03-14T20:45:23Z
dc.date.available2014-03-14T20:45:23Z
dc.date.issued2004-08-31en_US
dc.identifier.otheretd-09142004-151951en_US
dc.identifier.urihttp://hdl.handle.net/10919/35052
dc.description.abstractThe research presented in this thesis is all based on the impedance method for structural health monitoring. The impedance method is an electro-mechanical technique which utilizes a single piezoelectric transducer as both a sensor and actuator. Due to the high frequencies of excitation used for the method, the sensing area for damage detection can be very localized. Previous work has shown that wave propagation can be added to systems already equipped with hardware for impedance-based structural health monitoring. The work in this thesis shows what happens under varying temperature conditions for a structure being monitored with wave propagation. A technique to compensate for temperature fluctuations is also presented. The work presented here is an initial study to directly correlate the actual amount of damage in a composite specimen with a damage metric indicated by impedance-based structural health monitoring. Two different damage mechanisms are examined: transverse matrix cracking and edge delamination. With both composite defects, a sample is interrogated with the impedance method before and after damage is introduced. The exact amount of damage in each specimen is found using radiography and compared with the health monitoring results. Traditional impedance techniques require the use of a bulky and expensive impedance analyzer. With the trend of structural health monitoring moving towards unobtrusive sensors which can be permanently placed on a structure, an impedance analyzer does not lend itself to these small, low power consuming requirements. In this thesis, an initial attempt to miniaturize the hardware is described. A prototype impedance-based structural health monitoring system, incorporating wireless based communications, is fabricated and validated with experimental testing on a number of different structures. The first steps towards a complete self-contained, robust structural health monitoring sensor are presented.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartGrisso_Thesis.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectstructrual health monitoringen_US
dc.subjectwireless SHMen_US
dc.subjectimpedance methoden_US
dc.subjectwave propagationen_US
dc.subjectedge delaminationen_US
dc.subjecttransverse matrix crackingen_US
dc.titleConsiderations of the Impedance Method, Wave Propagation, and Wireless Systems for Structural Health Monitoringen_US
dc.typeThesisen_US
dc.contributor.departmentMechanical Engineeringen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineMechanical Engineeringen_US
dc.contributor.committeechairInman, Daniel J.en_US
dc.contributor.committeememberLeo, Donald J.en_US
dc.contributor.committeememberRobertshaw, Harry H.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-09142004-151951en_US
dc.date.sdate2004-09-14en_US
dc.date.rdate2004-09-15
dc.date.adate2004-09-15en_US


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