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Long Span Guard Rail over Low Fill Culverts, and Curbs

Question
State
Description Text	With the completion of NCHRP Report 537 on Recommended Guidelines for Curb and Curb Barrier Combinations, would you have any concerns with allowing a sloped mountable curb (height less than 100mm) to be installed with the sloped portion of the curb directly under the W-beam for the long span system? Based on my review of Report 537 recommendations for roads with speeds greater than 90km/h (p86), I think this combination would be OK for the long span system as well. Would you have any concerns?

Question

State

Description Text

With the completion of NCHRP Report 537 on Recommended Guidelines for Curb and Curb Barrier Combinations, would you have any concerns with allowing a sloped mountable curb (height less than 100mm) to be installed with the sloped portion of the curb directly under the W-beam for the long span system? Based on my review of Report 537 recommendations for roads with speeds greater than 90km/h (p86), I think this combination would be OK for the long span system as well. Would you have any concerns?

System Performance Evaluation
NCHRP 350
TL-3

System Types
W-beam Guardrails

Applications
Long-Span Guardrails

System Features

Date December 21, 2005
Previous Views (18) Favorites (0)

Response
Response (active)	With regard to long-span W-beam guardrail systems, we believe that there exists a reasonable chance that the standard long-span guardrail system would perform in an acceptable manner when placed over a 4-in. tall curb. This opinion also would correspond to the toe of the curb being positioned at the face of the guardrail. However, it should be noted that the long-span guardrail system with a lower 4-in. tall curb has not been evaluated according to the NCHRP Report No. 350 impact safety standards. In summary, we are reasonably confident that the long-span guardrail with noted curb would be okay to use on high-speed, high volume roadways.

Response

Response
(active)

With regard to long-span W-beam guardrail systems, we believe that there exists a reasonable chance that the standard long-span guardrail system would perform in an acceptable manner when placed over a 4-in. tall curb.

This opinion also would correspond to the toe of the curb being positioned at the face of the guardrail. However, it should be noted that the long-span guardrail system with a lower 4-in. tall curb has not been evaluated according to the NCHRP Report No. 350 impact safety standards. In summary, we are reasonably confident that the long-span guardrail with noted curb would be okay to use on high-speed, high volume roadways.

Date December 21, 2005
Previous Views (18) Favorites (0)