The 1974-79 study of the maintenance problems of the drawspan mechanism of the Evergreen Point Bridge across Lake Washington is reported. The approach was to predict the life of elements by Miner's hypothesis. For this the strains at critical points and the wind vector were measured over two sessions. These results were correlated with long term wind data to provide the number of cycles in a year at various stress levels. The fatigue capacity of anchor rods was determined by the Prot test on six specimens. The resulting S-N curve was compared to the field measurements to determine the expected life of the rods from the Miner criterion. The methods developed provide usable maintenance procedures for the prevention of fatigue failure of critical structural elements.
August 13, 2007
University of Washington. Dept. of Civil Engineering.
- # of Pages: 45 p., 691 KB (PDF)
- Subject: Anchor bolts, Failure, Fatigue (Mechanics), Pontoon bridges, Maintenance, Movable bridges, Rods, Strain (Mechanics), Structural deterioration and defects, Stresses, Wind.
- Keywords: Bridge, fatigue, floating bridges, reliability, wind, Lake Washington, Evergreen Point Bridge (Medina and Seattle)
- Related Publications: Evergreen Point Bridge Maintenance Problems, (First Annual Report), (WA-RD 44.2).
Evergreen Point Bridge Maintenance Problems, (Second Annual Report), (WA-RD 44.3).
Evergreen Point Bridge Maintenance Problems, (Third Annual Report), (WA-RD 44.4).
Evergreen Point Bridge Maintenance Problems, (Fourth Annual Report, (WA-RD 44.5).
This abstract was last modified April 29, 2008