MBGF with Round Wood Posts in Rocky Terrain

Report Number(s): 0-6946-R2

Description: The test installation consisted of a W-beam guardrail system with the top edge of the Wbeam rail mounted 31 inches above the roadway on nominal 7-inch diameter wood posts spaced at 6.25 ft. Routered wood blockouts, nominally 6 in. × 8 in., were inserted between the W-beam rail and posts, and the W-beam rail splices were located midspan between the posts. The guardrail was anchored on each end with a TxDOT DAT terminal making the total installation length 181.25 ft. An unreinforced concrete beam measuring 30 inches deep × 46 inches wide × 75 ft long was placed from post 10 to post 21 in the impact area of the length-of-need to simulate rocky terrain. Oval shaped voids measuring 12 inches wide × 22 inches long × 24 inches deep were cast in the beam at each post location to simulate holes cored in rock. The 7-inch diameter wood posts rested on the bottom of these voids with the traffic face of the post placed 1 inch from the front edge of the void. The voids were then backfilled with ASTM C33 coarse aggregate, size no. 57, and hand-tamped with a rod in 6-inch lifts.

Test Level: 3

MASH Test Number: 3-11

Proprietary/Non-proprietary: Non-proprietary

Pass/Fail: Fail

Evaluation: Full-Scale Crash Testing

Sponsor: Texas Department of Transportation