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dc.rights.licenseRestricted to current Rensselaer faculty, staff and students. Access inquiries may be directed to the Rensselaer Libraries.
dc.contributorLetchford, C. W.
dc.contributorO'Rourke, Michael J.
dc.contributorSymans, Michael D.
dc.contributor.authorRiedman, Michelle
dc.date.accessioned2021-11-03T07:58:31Z
dc.date.available2021-11-03T07:58:31Z
dc.date.created2013-09-09T14:30:30Z
dc.date.issued2013-05
dc.identifier.urihttps://hdl.handle.net/20.500.13015/853
dc.descriptionMay 2013
dc.descriptionSchool of Engineering
dc.description.abstractBecause of their inherent flexibility and low damping ratios, cantilevered mast-arm traffic signal structures are susceptible to wind-induced vibrations. These vibrations cause structural stresses and strains to develop in a cyclical fashion which can lead to reduced service life due to fatigue and, in extreme cases, full collapse.
dc.description.abstractTurbulence in the approach flow is known to affect the cohesiveness of vortex shedding. Results from this full-scale experiment indicate that the surrounding terrain conditions, which affect the turbulence intensity of the wind, greatly influence the likelihood of occurrence of long-lasting, high-amplitude vibrations and also impact whether reduced service life due to fatigue is likely to be a concern.
dc.description.abstractIn previous studies, high-amplitude vertical vibrations of mast-arm traffic signal structures have been shown to be due to vortex shedding, a phenomenon in which alternatingly shed, low-pressure vortices induce oscillating forces onto the mast-arm causing a cross-wind response. When the frequency of vortices being shed from the mast-arm corresponds to the natural frequency of the structure, a resonant condition is created. The resonant condition causes the long-lasting, high-amplitude vibrations which may lead to the fatigue failure of these structures.
dc.description.abstractIn 2001, after the collapse of several of these structures throughout the United States, American Association of State Highway and Transportation Officials (AASHTO) code standards were updated to include fatigue provisions for traffic signal supporting structures. In New York State, there is particular concern regarding structures spanning longer than 14 meters which currently do not meet these updated fatigue provisions. To address this concern, a full-scale experiment was conducted using an existing 25 meter mast-arm traffic signal structure, located in Malta, NY, in which the response of the structure was observed in relation to in-situ wind conditions.
dc.language.isoENG
dc.publisherRensselaer Polytechnic Institute, Troy, NY
dc.relation.ispartofRensselaer Theses and Dissertations Online Collection
dc.subjectCivil engineering
dc.titleFull-scale investigation of wind-induced vibrations of mast-arm traffic signal structures
dc.typeElectronic thesis
dc.typeThesis
dc.digitool.pid167070
dc.digitool.pid167071
dc.digitool.pid167072
dc.rights.holderThis electronic version is a licensed copy owned by Rensselaer Polytechnic Institute, Troy, NY. Copyright of original work retained by author.
dc.description.degreeMS
dc.relation.departmentDept. of Civil and Environmental Engineering


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