1 / 24

Trail Bridges – A Common Sense Approach to Selecting Bridge Sites

Trail Bridges – A Common Sense Approach to Selecting Bridge Sites. Presenter: James “Scott” Groenier, P.E. Project Leader, MTDC, WIT Prepared for: NOHVCC Conference Ontario, CA March 17, 2005. Introduction. Site Reconnaissance

lorant
Télécharger la présentation

Trail Bridges – A Common Sense Approach to Selecting Bridge Sites

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Trail Bridges – A Common Sense Approach to Selecting Bridge Sites Presenter: James “Scott” Groenier, P.E. Project Leader, MTDC, WIT Prepared for: NOHVCC Conference Ontario, CA March 17, 2005

  2. Introduction • Site Reconnaissance • Geomorphology Concerns • Hydrology and Hydraulics • Alignment • Environmental Concerns • Design Loads • Trail Bridge Website • Summary

  3. Site Reconnaissance • Site Investigation - simple

  4. Site Reconnaissance • Site Investigation - Complex Streambed strata Floodplain widths Soil types Logs in stream Ice Damage Drift locations Etc

  5. Site Reconnaissance • Site Survey Center of Stream Edge of water Bottom of Bank Top of Bank Floodplains Trail Utilities Roads Drift / Ice damage Etc Survey upstream and downstream for 300 ft Survey approaches on both sides 150 ft Survey top of banks for 30 ft

  6. Site Reconnaissance • Geotechnical Investigation Bedrock Loam

  7. Geomorphology Concerns From Rosgen’s “Field Guide for Stream Classification”

  8. Geomorphology Concerns • Stream Stability Deposition Area – Type C Channel Bedrock - Type A Channel Stable Banks – Type B Channel

  9. Geomorphology Concerns • Bank Stability

  10. Hydrology and Hydraulics + Regression Equations from USGS Reports on Estimating Frequency and Magnitude of Floods = Flow (CFS) • Waterway Adequacy • Hydrology

  11. Hydrology and Hydraulics • Waterway Adequacy • Hydraulics 1) Take CFS from Hydrology 2) Take Site Investigation info 3) Take Site Survey And Use a computer model such as HEC-RAS (River Analysis System) Or WinXSPRO And you get this….. HEC-RAS Example

  12. Hydrology and Hydraulics • Flooding –Spring, Fall or rain on snow Good or Bad Location?

  13. Hydrology and Hydraulics • Scour

  14. Hydrology and Hydraulics • Navigational Clearance 5 ft Minimum Required

  15. Alignment • Horizontal 90 degree Bend Straight

  16. Alignment • Vertical Bottom of Sag Curve Slight Grade

  17. Environmental Concerns • Fisheries • Spawning Areas, Fish passage • TES - Closures • Salmon • Bull Trout • Cutthroat Trout • etc • Wildlife • Nesting Trees, Rearing areas, etc • TES - Closures • Indiana Bat • Bald Eagles • Northern Goshawk • etc

  18. Environmental Concerns • Ice Flow • Floating Debris • Falling Trees • Falling Rocks • Excessive Snow Loads • Avalanche Chutes • Springs/Seeps • Wetlands • Others

  19. Design Loads • Dead Loads • Superstructure • Decking • Railing • Wearing Surface • Miscellaneous • Utility Lines • Covers

  20. Design Loads • Live Load • Pedestrian – 85 psf • Equestrian • OHV’s • Snowmobiles • Mountain Bikes • Vehicles • 5,000 width <6 ft • 10,000 6 ft<width<10 ft

  21. Design Loads • Snow Loads – 0 psf to over 350 psf • SNOTEL sites – 550 to 600 in the West • Local Building Officials • http://fsweb.mtdc.wo.fs.fed.us/snow_load/ • Wind Loads • Overloads • Groomers • 7600# - 18,000#

  22. Bridge Types • Trail Bridge Catalog • Forest Service Intranet - http://fsweb.mtdc.wo.fs.fed.us/bridges/ • Forest Service Internet - http://www.fs.fed.us/na/wit/WITPages/bridgecatalog/

  23. Bridge Fabrication/Supply • Structure produced by a certified Manufacturer for the type of material being used. - See “Contact Information For Wood and Steel Pedestrian and Trail Bridges” at National Wood In Transportation Website

  24. Summary • Site Reconnaissance • Geomorphology Concerns • Hydrology and Hydraulics • Alignment • Environmental Concerns • Design Loads • Trail Bridge Website • Questions?

More Related