NC Two-bar Metal Bridge Rail

Report Number(s): TRP-03-419-19

Description: It consisted of a 90-ft long concrete parapet with top-mounted aluminum posts and elliptical rails. The concrete parapet consisted of three 30-ft long segments with 1-in. wide gaps to replicate bridge expansion joints in between segments. The concrete parapet was 14-in. wide and 30-in. tall, except for the two tapered buttress ends at the upstream and downstream ends of the system. The rail system consisted of two elliptical aluminum rail segments that were attached to 16 vertical posts and base plate assemblies. Each post consisted of welded aluminum plates measuring 23½ in. tall and was mounted to a two-piece, cast aluminum base plate assembly, which was mounted to the top of the parapet through embedded bolts. Post nos. 6 through 13, where impact for Test 3-10 occurred, were spaced 72 in. apart. Post nos. 3 through 6, where impact for Test 3-11 occurred, were spaced 78 in. apart. Two elliptical rail segments were mounted on the front side of each aluminum post, through the rails' grooved back slots and clamp bars that were bolted to the posts. The mounting heights of the two aluminum rails were 10 in. and 22 in., respectively, measured vertically from the rail center to the top of the parapet.

Test Level: 3

Eligibility Letter: B-358

Barrier Type: concrete parapet and aluminum posts and elliptical rails

MASH Test Number: 3-10, 3-11

Proprietary/Non-proprietary: Non-proprietary

Pass/Fail: Pass

Evaluation: Full-Scale Crash Testing

Sponsor: North Carolina Department of Transportation