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dc.contributor.authorLoflin, Bryanen_US
dc.date.accessioned2014-03-14T20:40:55Z
dc.date.available2014-03-14T20:40:55Z
dc.date.issued2008-06-10en_US
dc.identifier.otheretd-06302008-073338en_US
dc.identifier.urihttp://hdl.handle.net/10919/33838
dc.description.abstractThe first objective of this thesis was to determine the material properties of grade 270 and grade 300 prestressing strand of various sizes. Tension tests were performed on each type of strand. The data from these tests was used to determine modulus of elasticity, yield stress, ultimate stress, and ultimate elongation for each strand. The yield stresses and ultimate stresses for many of the strands did not meet the requirements found in ASTM A416. The ultimate elongation results far exceeded the requirements and the measured elastic moduli were near the modulus recommended by AASHTO LRFD. A secondary objective from the tension tests was to evaluate a gripping method which used aluminum tubing to cushion the strands against notching. The grips performed very well. Most of the strand breaks did not occur in the grips and when a strand did break in the grips, the failure occurred after significant post-yield elongation. The second objective was to evaluate the bond properties of grade 270 and grade 300 prestressing strands. The North American Strand Producers (NASP) Bond Test and Large Block Pullout Test (LBPT) were performed on six different strand grade and strand size combinations. Both of the tests are simple pullout tests on untensioned strand. The results for each strand type were compared to one another as well as to measured transfer and development lengths from beams using the strand from the same reel. All of the strands showed sufficient bond in the beams, but one strand type did fail both the NASP Test and the LBPT. Both pullout tests were acceptable methods to evaluate strand surface condition and the benchmarks set for 0.5 in. diameter regular strand were conservative for the strands used in this thesis. Little difference was evident in the bond performance of grade 270 and grade 300 prestressing strand.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartLoflinThesis.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.subjecttension testsen_US
dc.subjectgrade 270 stranden_US
dc.subjectgrade 300 stranden_US
dc.subjectprestressing stranden_US
dc.subjectdevelopment lengthen_US
dc.subjecttransfer lengthen_US
dc.subjectprestressed concreteen_US
dc.subjectpullout testsen_US
dc.titleBond and Material Properties of Grade 270 and Grade 300 Prestressing Strandsen_US
dc.typeThesisen_US
dc.contributor.departmentCivil Engineeringen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
dc.contributor.committeememberCharney, Finley A.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-06302008-073338/en_US
dc.contributor.committeecochairRoberts-Wollmann, Carin L.en_US
dc.contributor.committeecochairCousins, Thomas E.en_US
dc.date.sdate2008-06-30en_US
dc.date.rdate2008-07-28
dc.date.adate2008-07-28en_US


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