Safety barriers provide forgiving roadsides for highways while their test performance should comply with uniform norms, e.g. EN1317. When selecting a barrier type for a median, the dilemma frequently compares between in-situ concrete and other barriers. In-situ concrete barriers require less space for their installation and rare maintenance, while steel guardrails can deflect, but require a wider median and higher maintenance, with associated crash risks during repair roadworks. This study compared the safety performance of highways with various median barrier types, in Israel, aiming to provide a background for more effective use of safety barriers. The study examined four barrier types: Step-shaped in-situ, pre-cast concrete and steel guardrails, as new barrier types (which satisfy the EN1317), and old NJ-shaped in-situ barriers. The database included 558 km of non-urban Israeli highways. Negative-binomial regression models were fitted for predicting crashes, and differences in crash expectancy were evaluated for various barrier types, while controlling for traffic volumes and other road infrastructure characteristics. The results showed that, on dual-carriageway roads, sections with Step-barriers had a better safety level relative to those with NJ-barriers and, sometimes, to other barrier types. On motorways, the safety level of sections with Step-barriers was better or similar to that with NJ-barriers, with no difference compared to the pre-cast barriers, while sections with steel guardrails had a better safety level, particularly at traffic volumes over 40,000 vehicles. The economic evaluations showed benefits for replacing the old NJ-barrier by a Step-barrier, on dual-carriageway roads, and by steel barriers, on motorways.
A Comparative Evaluation of the Safety Performance of Median Barriers on Rural Highways; A Case-Study
Sustain. Civil Infrastruct.
International Road Federation World Meeting & Exhibition ; 2021 ; Dubai, United Arab Emirates November 07, 2021 - November 10, 2021
2022-04-21
18 pages
Aufsatz/Kapitel (Buch)
Elektronische Ressource
Englisch
Median Cross-Section Design for Rural Divided Highways
NTIS | 2014
|Safety Index for Evaluation of Two-Lane Rural Highways
Transportation Research Record | 2007
|Median Treatment Study of Washington State Highways
NTIS | 2002
|Safety Index for Evaluation of Two-Lane Rural Highways
Online Contents | 2007
|