DETERMINATION OF CRASH BARRIER RUNOUT LENGTHS FOR EXPRESSWAYS IN INDIA BASED ON CRASH DATA ANALYSIS (Paper 844)

An analysis of crash data from the Mumbai Pune Expressway between October 2012 and September 2016 (4 years) showed that 51% of the crashes (390 out of 773) investigated were run-off from road crashes. Of the 390 run-off road crashes, 66% (256 out of 390) had an object impact subsequent to the vehicle leaving the carriageway. For the purpose of this study, 70 crashes involving run-off road vehicles impacting trees, overhead bridge pillars, underpasses and concrete structures were selected and studied. It was found that collectively these 4 roadside/median hazards contributed to 11% of fatalities and 7% of seriously injured victims. Further analyses of the 70 crashes also showed that crash barriers were provided only in 6% (4 out of 70) of the crash locations. In all the 4 locations where crash barriers were available during the time of impact, the length of the installed crash barriers was not effective in preventing the run-off vehicles from impacting the roadside/median obstacles. The objective of this study is to determine the minimum upstream length of guardrails required for these roadside/median hazards on the expressway using crash data analysis. The findings of the analysis recommended a desired minimum runout lengths of 60 meters, 46 meters, 47 meters and 47 meters of guardrail installation for the hazards concrete structures, trees, overhead bridge pillars and underpasses respectively.