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dc.contributor.authorNajafi, Shahriaren_US
dc.date.accessioned2015-02-02T20:32:56Z
dc.date.available2015-02-02T20:32:56Z
dc.date.issued2010-12-07en_US
dc.identifier.otheretd-12132010-111100en_US
dc.identifier.urihttp://hdl.handle.net/10919/51244
dc.description.abstractIt is the responsibility of pavement engineers to design pavements that provide safe and smooth riding surfaces over their entire life cycle. Each year many people around the world lose their lives in vehicle crashes, which are one of the leading causes of death in the United States (US). One of the contributing factors in many of these crashes is inappropriate friction between tires and the pavement. To minimize the impact of this factor, state Departments of Transportation (DOTs) must monitor the friction of their pavement networks systematically and regularly. Several devices are used around the world for measuring friction. Locked-wheel skid trailers are the predominant technology for roadways in the U.S. However, Continues Friction Measuring Equipment (CFME) is emerging as a practical alternative, especially for network-level monitoring. This type of technology has been used for monitoring runway friction for many years and is starting to be used also for measuring roadway friction. This thesis evaluates the different operational characteristics of CFME to provide guidelines for highway agencies interested in using this technology for supporting their friction management programs. It follows a manuscript format and is composed of two papers. The first part of the thesis presents a methodology to objectively synchronize and compare CFME measurements using cross-correlation. This methodology allows for comparing the “shape” of the friction profiles, instead of only the average friction values. The methodology is used for synchronizing friction measurements and assessing the repeatability and reproducibility of the CFME using friction measurements taken on a wide range of surfaces at the Virginia Smart Road. The proposed approach provides highway agencies with a rigorous method to process CFME measurements. The second part of the thesis evaluates the impact of several operational characteristics on the CFME measurements using a field experiment. The results of the experiment confirmed that the measurements are significantly affected by (1) the direction of testing while testing on sections of road with a significant grade, (2) water film thickness, and (3) testing speed. The experiment showed that measurements taken downhill on a 6% grade were significantly higher than those taken uphill. The analysis also verified that, consistent with previous studies, the measured friction decreases with higher water depth and testing speeds. It also showed that the change of friction with speed is approximately linear over the range of speeds used in the experiment. In general, the thesis results suggest that CFME can provide repeatable and reproducible friction profiles that can be used to support friction management programs and other asset management business functions. However, care should be taken with regard to the operational conditions during testing since the measurements are affected by several factors. Further research is needed to (1) quantify the effect of these, and potentially other, operational factors; and (2) establish standard testing condition and approaches for correcting measurements taken under other conditions.en_US
dc.format.mediumETDen_US
dc.language.isoen_USen_US
dc.publisherVirginia Techen_US
dc.relation.haspartNajafi_Shahriar_T_2010.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.subjectlocked wheelen_US
dc.subjectCFMEen_US
dc.subjectrepeatabilityen_US
dc.subjecttesting devicesen_US
dc.subjectsafetyen_US
dc.subjectpavementen_US
dc.subjectreproducibilityen_US
dc.subjectfrictionen_US
dc.titleEvaluation of Continuous Friction Measuring Equipment (CFME) for Supporting Pavement Friction Management Programsen_US
dc.typeThesisen_US
dc.contributor.departmentCivil and Environmental 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.disciplineCivil and Environmental Engineeringen_US
dc.contributor.committeechairFlintsch, Gerardo W.en_US
dc.contributor.committeememberIzeppi, Edgar D. de Leonen_US
dc.contributor.committeememberMcGhee, Kevin K.en_US
dc.contributor.committeememberWang, Linbingen_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-12132010-111100/en_US
dc.date.sdate2010-12-13en_US
dc.date.rdate2015-02-02
dc.date.adate2010-12-28en_US


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