?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.relation=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F6513%2F&rft.title=Fatigue+Life+Estimation+of+a+Highway+Sign+Structure&rft.creator=Kacin%2C+Jennifer+Ann&rft.description=Sign+structures+stand+along+every+highway+and+interstate+across+the+country+in+order+to+guide+motorists+to+their+destination.+Such+structures+are+repeatedly+subjected+to+natural+wind+gusts+and+gusts+from+vehicles+passing+underneath.+Over+time%2C+the+members+within+the+structure+may+begin+to+succumb+to+fatigue+due+to+this+cyclical+loading%2C+in+the+form+of+cracks+in+the+members+and+in+the+connections.+The+goal+of+this+project+is+to+determine+the+fatigue+life+of+an+overhead+four-chord+truss+sign+structure+located+in+Pennsylvania+in+both+a+damaged+and+undamaged+state.+A+finite+element+model+of+the+structure+was+made+using+commercial+software+and+a+time+varying+natural+wind+load+was+applied+to+it.+The+stress+history+of+critical+elements+was+then+extracted+from+the+model's+solution.+Complete+stress+cycles+were+counted+and+then+a+linear+damage+accumulation+method+was+used+in+order+to+find+the+fatigue+life+in+the+critical+members.+The+non-damaged+structure's+critical+members+were+found+to+have+an+infinite+fatigue%2C+as+were+the+damaged+structure's+critical+members.+Despite+this%2C+members+with+welded+connections+should+still+be+closely+monitored+during+inspection+because+they+have+the+highest+potential+for+failure.&rft.date=2009-06-29&rft.type=University+of+Pittsburgh+ETD&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.language=en&rft.identifier=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F6513%2F1%2FKacin_pittetd2009.pdf&rft.identifier=++Kacin%2C+Jennifer+Ann++(2009)+Fatigue+Life+Estimation+of+a+Highway+Sign+Structure.++Master's+Thesis%2C+University+of+Pittsburgh.++++(Unpublished)++