Bicycle Railing Height Report - AASHTO - Subcommittee on Design

DETERMINATION OF APPROPRIATE RAILING HEIGHTS FOR BICYCLISTS
NCHRP 20-7 (168)
Chapter 3 - Existing State of Art of <strong>Bicycle</strong> <strong>Railing</strong>
Design
Existing Policy
In 1998, the Federal Highway Administration (FHWA) adopted a policy to improve
conditions and safety for bicycling and walking and create an integrated, intermodal
transportation system, which provides travelers with a real choice of transportation
modes. This policy was adopted under the passing of legislation for the Transportation
Equity Act for the 21 st Century (TEA-21). The FHWA guidance paper, “<strong>Bicycle</strong> and
Pedestrian Provisions of Federal Transportation Legislation” (1999) provides the
agency’s position on the matter:
“TEA-21 confirms and continues the principle that the safe accommodation of
non-motorized users shall be considered during the planning, development, and
construction of all Federal-aid transportation projects and programs. To varying extents,
bicyclists and pedestrians will be present on all highways and transportation facilities
where they are permitted and it is clearly the intent of TEA-21 that all new and improved
transportation facilities be planned, designed, and constructed with this fact in mind”.
As such, this policy statement provides guidance to transportation facility designers that
they should not disregard the importance of bicycling as a transportation mode, and
transportation facilities should be designed with their accommodation in mind.
Existing Guidelines
Guidelines exist at the federal, international, state, and local levels for the design of
railings for bicyclists.
<strong>AASHTO</strong> Guidelines for Bridges
During the design of a highway bridge, designers typically select a railing based on the
type of traffic that is anticipated for the bridge. For guidance, designers use the 1989
<strong>AASHTO</strong> “Standard Specifications for Highway Bridges,” combined with any state
policies or guidelines. In 2007, the <strong>AASHTO</strong> “Load Resistance Factor Design (LRFD)
Bridge Design Specifications” will become the national standard for guidance.
On bridges that serve primarily vehicular traffic, such as a bridge along a limited access
highway, designers generally select a bridge railing that is designed for vehicular
applications. If a sidewalk or designated bicycle facility is included in the design of a
bridge, designers select the most appropriate railing design for the multi-modal
environment.
Determination of <strong>Railing</strong> Requirements
There are three types of railings that are routinely specified on bridges that are designed
for vehicle loadings:
• Vehicular or traffic railing – Designed to protect only vehicles
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