213 - Railings

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213.7 - TRAFFIC RAILING

213.7.3 - Railing Design

213.7.3.2 - Height of Traffic Parapet or Railing

SPECIFICATIONS COMMENTARY
The following shall replace A13.7.3.2:

Traffic railings shall be at least 31.0 inches in height for TL-3, 36.0 inches for TL-4, 42.0 inches for TL-5, and 90.0 inches for TL-6.

The bottom 3.0-inch lip of the safety shape shall not be increased for future overlay considerations.

The minimum height for a concrete parapet with a vertical face shall be 36.0 inches. The height of other combined concrete and metal rails shall not be less than 36.0 inches and shall be determined to be satisfactory through crash testing for the desired test level.

Bicycle railings shall be at least 42.0 inches in height. The minimum height of the pedestrian or bicycle railing should be measure above the surface of the sidewalk of the bikeway.

The minimum geometric requirements for combination railings beyond those required to meet crash test requirements shall be taken as specified in Articles 13.8, 13.9, and 13.10.

C213.7.3.2

The following shall supplement AC13.7.3.2.

The minimum suggested guardrail height for TL-3 is increased to 31.0 inches based upon the recommendations of FHWA Memo ACTION: Roadside Design: Steel Strong Post W-beam Guardrail, May 17, 2010. The minimum railing height for TL-3 is increased to provide consistency between the bridge barrier and approach guardrail heights and to avoid the need for a transition.

On bridges where bicycle speeds are likely to be high (such as on a downgrade) and where a bicycle could potentially impact the railing at an angle of 25 degrees or greater (such as on a curve), a 48.0-inch high railing may be considered.