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Trail Bridges – Details for Longevity, Condition Assessments and Annual Maintenance. Presenter: James “Scott” Groenier, P.E. Project Leader, MTDC, WIT Prepared for: NOHVCC Conference Ontario, CA March 17, 2005. Introduction. Construction
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Trail Bridges – Details for Longevity, Condition Assessments and Annual Maintenance Presenter: James “Scott” Groenier, P.E. Project Leader, MTDC, WIT Prepared for: NOHVCC Conference Ontario, CA March 17, 2005
Introduction • Construction - Details For Longevity • Condition Assessments • Annual Maintenance • Summary
Construction • Details for Longevity • Durability and Design details by Kropf Available from WIT on CD “The National Wood in Transportation Program” • Controlling Decay in Waterfront Structures by Highly & Scheffer http://www.fpl.fs.fed.us/documnts/fplrp/fplrp494.pdf
Construction • Details for Longevity • Shedding water off Structures • Beveled Top Rails • Raised Low Rails
Construction • Details for Longevity • Shedding water off Structures • Scupper blocks for Curbs
Construction • Details for Longevity • Structure Protection • Side Rails • Wearing Surface
Construction • Details for Longevity • Shedding water off Structures • Bridge Gradients
Construction • Details for Longevity • Approach Ditches • Cross Drains
Construction • Details for Longevity • Earth-Wood Interface • Screwing vs. Nailing
Construction • Weathering Steel Corrosion Problems • Technical Advisory – T5140.22http://www.fhwa.dot.gov/legsregs/directives/techadvs/t514022.htm • Environment • Marine Coastal Areas • Frequent High rains, High Humidity or Persistent fog • Locations to avoid • Tunnel Like Conditions • Low Water Crossings • 10 feet – over stagnant water • 8 feet – over moving water
Construction • Corrosion problems with new wood treatments http://www.strongtie.com/productuse/corrosion.html • Conclusion from Technical Bulletin • Certain treatments are more corrosive than CCA. • Treated wood industry recommends use of Stainless Steel or Hot-dip Galvanized fasteners and connectors. • Check to make sure fasteners, connectors and wood treatment type are compatible.
Condition Assessment • Timber Bridges – Maintenance, Rehabilitation and Replacement by Muchmore • Website for free publications: http://spfnic.fs.fed.us/wit/WITpubs/PubSearch.cfm • Bridge Inspection / Assessment • FS requires every 4 years • Trail Bridge Matrix
Condition Assessment • Bridge Assessment Forms
Condition Assessment • Stream Bank Scour
Condition Assessment • Foundation and Substructure
Condition Assessment • Stringers and Beams
Condition Assessment • Decking and Wearing Surface
Condition Assessment • Railing and Curbing
Annual Maintenance • Cleaning Decks
Annual Maintenance • Cleaning Tops of Sills
Annual Maintenance • Bridge Approaches
Annual Maintenance • Other Items • Cleaning Tops of Beams • Clearing Brush • Nailing and Replacing Decking • Repairing banks
Summary • Construction - Details For Longevity • Condition Assessments • Annual Maintenance • Questions?