Evaluation of the rate of reducing speed and acceleration as safety indicators for high-speed buses drivers in Tehran

Although the history of traffic violations and accidents of drivers largely reflects their driving status and skills, but because this data is passive in nature, in recent years, researchers have proposed approaches that are preventive in nature and can be used as alternative indicators instead of accident data. The rate of change of speed and the rate of change of acceleration while driving are among the indicators that have received a lot of attention recently. These two indicators are derived from drivers' field behavior. In the present study, it has been tried to examine the mentioned indicators as a criterion for measuring the safety of their behavior by using the speed profile of drivers. Due to the high importance of reducing drivers 'driving risk, public transportation modes, especially high-speed buses modes (due to higher speeds and higher capacity compared to conventional buses) as well as the lack of similar studies in the field of risk analysis of drivers' field behavior of this fashion in the country, the present study has examined the mentioned indicators in the high-speed buses lines of Tehran.

In this study, first the structure and method of measuring these two indicators are reviewed and then in order to investigate the correlation of these indicators with accidents, 176 high-speed bus drivers in Tehran (lines 3 and 5) is studied with the use of smartphone positioning system and the is calculated correlation between the indicators obtained from the field behavior of drivers and their accident history.

Both indicators obtained from drivers 'field behavior while driving had a positive and significant correlation with drivers' accidents in the last two years. The acceleration change rate index had a significantly higher correlation with drivers' accidents and the threshold of 2 m / 3 s had the highest correlation among the thresholds of this index which was selected as the critical threshold.

According to the obtained correlation results, the mentioned indicators can be used to assess the safety of field behavior of drivers of the fleet of high-speed buses lines. Also, the higher correlation of the acceleration reduction rate compared to the speed reduce rate indicates the better performance of this index in the analysis of drivers' field behavior.