Mash Test Designation Nos 3 11 3 17 Of A Non Proprietary High Tension Cable Median Barrier With Closed Sections Post PDF Download

In the early 2000s, MwRSF conducted full-scale crash testing on low-tension cable barrier systems installed adjacent to 1.5H:1V slopes. A design was successfully tested according to NCHRP Report 350 criteria, but the tested and approved configuration utilized a 4-ft (1.2 m) post spacing and a 4-ft (1.2 m) offset from the slope break point (SBP). Therefore, NDOT funded this research study to investigate if revisions to the low-tension cable barrier system could be identified which were likely to satisfy MASH requirements and which would be more cost-effective. This research study was conducted to investigate alternative low-tension cable barrier designs and configurations which would be likely to satisfy MASH TL-3 impact conditions and which would improve cost-effectiveness and/or usability for NDOT. Test nos. LTCB-1 through LTCB-5 were conducted on S3x5.7 steel posts at varying offset distances from a 1.8H:1V slope. Test no. LTCB-6 was conducted to evaluate the propensity for S3x5.7 posts to penetrate a small car test vehicle's floor pan, and tearing was observed. Subsequent component tests of an HSS3x2x1/8 tubular post alternative in development for use with high-tension cable median barrier systems was found to provide acceptable performance while mitigating floor pan tearing. Computer simulations were performed to investigate alternative barrier configurations. Various combinations of post spacing, barrier offset, and cable heights were evaluated. It was determined that systems with 3-ft (0.9-m) offset from the slope with 4-ft (1.2-m) post spacing, or 4-ft (1.2-m) offset from the slope with 6-ft (1.8-m) post spacing, may perform acceptably according to MASH TL-3 test designation no. 3-11.