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Curb termination or transition below MGS stiffness transition

Question
State	WI
Description Text	When utilizing the 4" curb under the MGS stiffness transition to a thrie beam approach guardrail transition, where is the appropriate location to either terminate the curb or transition to a taller 6" curb (e.g., the MGS system designed to use behind a 6" curb)?

System Performance Evaluation

System Types
Approach Guardrail Transitions (AGTs)

Applications

System Features

Date September 18, 2013
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Response
Response (active)	The 4" curb should be extended out from the bridge parapet, through the entire transition area including all 1/2 post (37.5") spacings, and continue through a minimum of one full post (75") spacing. Thus, termination of the curb or a transition to a 6" curb may occur within the 2nd full post spacing upstream of the stiffness transition. Additionally, it is recommended to utilize a minimum length of 3 ft to transition from a 4" wedge shaped curb to a 6" high, AASHTO Type "B" curb. The 3 ft length would also apply for the termination length (transitioning from a 4" curb to no curb).

Response

Response
(active)

The 4" curb should be extended out from the bridge parapet, through the entire transition area including all 1/2 post (37.5") spacings, and continue through a minimum of one full post (75") spacing. Thus, termination of the curb or a transition to a 6" curb may occur within the 2nd full post spacing upstream of the stiffness transition.

Additionally, it is recommended to utilize a minimum length of 3 ft to transition from a 4" wedge shaped curb to a 6" high, AASHTO Type "B" curb. The 3 ft length would also apply for the termination length (transitioning from a 4" curb to no curb).

Date September 18, 2013
Previous Views (119) Favorites (0)