TTI Research Supervisor:
Chiara Silvestri Dobrovolny, Ph.D.
Associate Research Scientist
Texas A&M Transportation Institute
College Station, Texas 77843-3135
(979) 845-8971 [email protected]
Pooled Fund Technical Representative:
Jeff C. Jeffers, P.E.
Statewide Standard Specifications
Alaska Department of Transportation & Public Facilities
3132 Channel Drive
P.O. Box 112500
Juneau, AK 99811-2500
(907) 465-8962 [email protected]
Buried (in backslope) terminal designs for beam guardrail were developed under National Cooperative Highway Research Program (NCHRP) Report 350 criteria 27¾-inch high guardrail systems. Some states have modified this design so that it could be used with 31 inch high guardrail systems. Other agencies are hesitant to use this design for 31-inch high guardrail until it is crash tested or deemed acceptable for use by Federal Highway Administration.
The purpose of this research was to evaluate the safety performance of a 31-inch Buried-in-Backslope (BIB) terminal attached to a Midwest Guardrail System (MGS) in accordance with American Association of State Highway and Transportation Officials (AASHTO) Manual for Assessing Safety Hardware (MASH) evaluation criteria.
Two tests were performed to evaluate the proposed design for a TL-3 BIB Terminal compatible with an MGS guardrail system. They represent the tests considered necessary to demonstrate MASH compliance of the device. The TL-3 BIB Terminal system met MASH requirements and is considered MASH compliant. It is considered suitable for implementation at V-ditch locations with a 4:1 or flatter foreslope where a MASH TL-3 BIB Terminal system is needed and/or desired.