01516028

Component

https://doi.org/10.3141/2437-06

http://scholar.google.com...Reid&publication_year=2014

Approach guardrail transition systems have been designed, tested, and evaluated according to various impact safety standards. Unfortunately, approach guardrail transitions that are installed in the field may deviate from the as-tested configuration (e.g., by missing posts); this deviation reduces the desired lateral stiffness and strength of the transition system. Validated BARRIER VII computer models of 18-ft 9-in. (5.7-m)-long and 31-ft 3-in. (9.5-m) long systems of NCHRP Report 350 crashworthy approach guardrail transitions were used to gain an understanding of how they would perform, with and without deficiencies, when subjected to Test Level 3 impacts at various locations throughout each system. Each simulation was evaluated on the basis of three criteria: (a) maximum wheel-rim snag on the upstream edge of the bridge rail, (b) maximum dynamic deflection within the nested Thrie section, and (c) maximum vehicle pocketing angle within the nested Thrie section. According to simulation results, when transition posts were missing, installed adjacent to sloped terrain, or exposed more than 3 in. (76 mm), excessive dynamic deflection or vehicle snag on the upstream end of the bridge rail could occur. Recommendations and retrofits are provided to upgrade approach guardrail transitions for the safest performance.

01543380

14-4613

English

pp 52–62

2014

Transportation Research Record: Journal of the Transportation Research Board

9780309295253

Print

Figures (5) ; Photos; References (18) ; Tables (1)

Guardrail transition sections; Highway safety; Retrofitting; Simulation

BARRIER VII (Computer program)

Design; Highways; Safety and Human Factors; I85: Safety Devices used in Transport Infrastructure

PRP, TRIS, TRB, ATRI

Jan 27 2014 3:36PM

• Further Considerations for Effective Median Barrier Lateral Placement for Varying Highway Cross Sections
• Method for Modeling Crash Severity with Observable Crash Data
• Performance of the Midwest Guardrail System with Rectangular Wood Posts
• Pinned-Down Temporary Concrete Barrier with Transition Systems for Limited-Space Work Zone Applications
• Selection Table Development for Bridge Railing
• Understanding of Heavy-Vehicle Encroachment Frequency
• Weak-Post W-Beam Guardrail Attachment to Culvert Headwalls