AWAM International Conference on Civil Engineering 2019 (AICCE'19) - Nibong Tebal - Malaysia (2019-08-21)

Serious Conflicts A Safety Performance Measure at Signalized Intersections
There is a challenge to identify potential sites for safety improvement in case of shortage in crash data. This study explores alternative method based on a traffic conflict as a surrogate safety measure instead of crash data. The study demonstrates two family major safety assessment streams; a crash-based measure proposed by Highway Safety Manual and a traffic conflict-based method. For crash -based method, Empirical Bayes method (EB-method) had been used as a benchmark. Conventional crash Frequency and crash rate measures are used as a direct supplement. Further, conflicts based on two surrogate safety indicators had been used in the conflict-based methods. The safety measures are estimated and compared through Pearson correlation analysis while hazard location identification results are compared based on rank positions. Results showed that the serious conflicts frequency as a conflict-based method had a high correlation and a coefficient of 0.986 with the EB-method in the resulting outcomes and performed better than crash frequency method in identifying hazard location when compared with EB-method. Therefore, the serious traffic conflict-based method can serve as a viable option for safety performance evaluation and hazard locations identification, especially when sufficient crash data are not obtainable.
Ms. Raghad Abdul-Majeed, Professor Hussein Ewadh