TRAILS AS TRANSPORTATION Design & Construction Michael J. Kubek, P.E. Ohio Department of Transportation, District 12 Production Administrator
Before Design Secure funding source Determine logical termini Coordinate with oversight agency
Determine Logical Termini –Best to develop a master plan
Determine Logical Termini –Best to develop a master plan
Before Design Determine Logical Termini –Federal requirement –Best to develop a master plan –Common termini Connection to an existing trail Park facility Designated bike route
–Common termini Designated bike route
–Common termini Designated bike route
–Common termini Designated bike route
Before Design Remember: Rails to Trails are not always a slam dunk. Consider the following: –Typical section –Drainage issues –Environmental issues –Right of Way –Utilities
TRAILS AS TRANSPORTATION Design
Design References AASHTO “Guidelines for the Development of Bicycle Facilities,” (1999 or latest edition)
Design References
FHWA Publication No. FHWA-EP , “Best Practices Design Guide Part 2, Designing Sidewalks and Trails for Access,” (2001)
Design References AASHTO “Guidelines for the Development of Bicycle Facilities,” (1999 or latest edition) FHWA Publication No. FHWA-EP , “Best Practices Design Guide Part 2, Designing Sidewalks and Trails for Access,” (2001) OMUTCD “Ohio Manual of Uniform Traffic Control Devices (2005 or latest edition, Chapter 9) Additional References –ODOT Office of Local Projects web site –ODOT District 12 LPA website, Phase II Design spx spx spx –Local MPO (Metropolitan Planning Organization)
Types of Bicycle Facilities Bike Lane Shared Use Path (aka Bike Path) –A facility shared by recreational users (i.e. pedestrians, joggers, bicyclists, etc.) separated from roadway traffic. The design standards used for the bicycle facility shall be determined by the use of the facility.
TRAILS AS TRANSPORTATION Shared Use Path Design
Typical Section Width –Path Width = 10’ –Graded Shoulder = 2’ –Bridge or Tunnel Width = 14’ Cross Slope –Path Slope = 2% pref., 3% max No crown is preferred –Graded Shoulder = 12:1 pref., 6:1 max Design Speed 20mph 30mph (advisable for profile grades > 4%)
Typical Section Pavement Composition –Design for expected emergency, law enforcement, & maintenance vehicles –ODOT commercial drive design is recommended
Typical Section Horizontal Clearance –Obstructions = 3’ desired, 2’ min. –Separation from Roadway = 5’ –Steep Embankment (> 3:1) = 5’ Vertical Clearance –10’ desired, 8’ min.
Typical Section
Horizontal Alignment Max. Grade Break w/o horizontal curve –Not addressed directly in AASHTO –Use taper formula for obstructions on page 67 of the manual
Horizontal Alignment Minimum Radius of Curvature –AASHTO Table 1, page 38 20mph = 100’ 30mph = 225’
Horizontal Alignment Minimum Lateral Clearance for Horizontal Curves –AASHTO Table 4, page 45
Horizontal Alignment The preceding criteria establishes the threshold for safety in design. Remember to include an aesthetically pleasing and enjoyable facility.
Vertical Alignment Max. Grade Break w/o a vertical curve –Not addressed directly in AASHTO –Use ODOT Location & Design Manual (L&D) Figure 20mph = 2.9% 30mph = 1.30% Minimum length of vertical curve –Establish Stopping Sight Distance (SSD) for crest curve
Vertical Alignment Minimum length of vertical curve –Based on Stopping Sight Distance (SSD) for crest curve –AASHTO manual states 3 feet –ODOT District 12 recommends 3 * Design Speed (pref.) 2 * Design Speed (min.)
Vertical Alignment Maximum length of steep profile grades –AASHTO page 70
Vertical Alignment Maximum length of steep profile grades –FHWA page 16-5
Vertical Alignment Maximum length of steep profile grades 5% < Grade ≤ 6%up to 800ft 6% < Grade ≤ 7%up to 400ft 7% < Grade ≤ 8%up to 300ft 8% < Grade ≤ 8.33%up to 200ft * 8.33% < Grade ≤ 10%up to 30ft * 10% < Grade ≤ 12.5%up to 10ft *
Vertical Alignment Maximum length of steep profile grades –Exception: when the path is adjacent to a roadway, it can follow the roadway profile.
Vertical Alignment
ADA Compliance ADA (Americans with Disabilities Act) Curb Ramps –Provide truncated domes
ADA Compliance Accessibility –The trail (shared use path) is considered a “Facility.” –Access to the facility is subject to the ADAAG (Americans with Disabilities Act Accessibility Guidelines)
ADA Compliance
Drainage Use Bicycle safe grates (4” max. grid spacing) Provide ditch on uphill side of the path Culvert design per ODOT Location & Design Manual Volume 2, Section Ditch flow depth per L&D section (District 12) –9” below edge of path, pref. –0” below edge of path, min. Do not put the safety of the users at risk!
Vehicular Crossings Pave drives for at least 10’ on each side of the path
Vehicular Crossings Signing and striping per AASHTO manual and the OMUTCD (Chapter 9 for bicycles)
Vehicular Crossings Signing and striping per AASHTO manual and the OMUTCD (Chapter 9 for bicycles)
Vehicular Crossings Slow down users with geometrics & provide SSD at intersection
Vehicular Crossings Slow down users with geometrics & provide SSD at intersection
Design Exceptions Prepare in accordance with ODOT L&D, Volume 1, section 105 Submit with letter of concurrence from the Local Public Agency (owner & maintaining agency) Design standards that are “advisable” or “recommended” generally do not require a design exception
Design Exceptions
Other Design Considerations Account for clean up in the bid, especially on urban trails Design bridges for emergency and maintenance vehicle loading Construction –Construction equipment loading Soils investigation –Staging areas Utilities in Railroad Corridors –Petroleum lines –Fiber Optic
Design Summary Planning –Secure Funding –Master Plan –Logical Termini Design –Use Common Sense –Always keep the safety of the user as your number one priority –Design as if your family will be using the facility