Investigation on Contributory Factors to Accident Severity and Crash Loss Value: A Case Study on Addis Ababa–Adama Expressway

Abstract

Road traffic accidents occur due to several factors associated with traffic system. The cause of traffic accident can be group in to four main factors, namely: human factors, vehicle factors, road factors and environmental factors. Road traffic accidents (RATs) are currently serious and major public health problem in developed and developing countries. In developing countries like Ethiopia RTAs are among the leading and top cause of death and injury. Nowadays in Ethiopia road fatalities and injuries are major killer problem. The expressway that connects Addis Ababa to Adama is one of new and latest among the roads in Ethiopia. But the accident occurred on expressway increase day to day. The occurrence of the accident has many contributory factors. However, among the contributory factors it is vital to select major factors and give measures how prevent the causes. The main objective of the study was to investigate the contributory factors to accident severity and the crash loss values on the expressway. Primary and secondary data used to meet the objective of the thesis. Primary data collected by questionnaires were distributed to drivers and interview also made. Secondary data was collected from Ethiopian toll road enterprise. During the study period 2014/15 to 2016/2017 total of 1171 reported accidents was collected and out of this 70 fatalities 147 serious, 344 lights and 610 properties damage were reported. To analyze the data descriptive analysis and statistical package for social science was used. The result of the study showed that higher traffic accident cause by male drivers compared to female drivers. Also the study finds the age groups of 18-30 were mostly affected age of drivers. From the day of the week Sunday was the highest traffic accident were recorded. And also accidents varies throughout the time of the day, hence starting from mid-day (12:00PM) to night time (6:00PM) were the highest accident were recorded. During dry surface condition and straight and level of road character the occurrence of the accident were highest. The reported data on the expressway shows most of accidents occurred by vehicle type of bus (13-65 seats), automobiles and truck (11-40 quintals). Due to this the occurrence of the accident on the expressway an average 32,240,400 birr was loss. The result shows age of driver, sex of driver, time of day, day of week, road character, surface condition, weather condition and possible causes reported by traffic police (over speed, unethical driving (reckless driving, driving under influence, fatigue, not use seat belts, sleeping, breaking problem, tire problem, animal entrance and technical problem) have statistically significant impact on the occurrence of accidents. Based on reported and surveyed data the cause and contributing factors on the expressway were over speed, unethical driving (reckless driving, driving under influence), fatigue, not use seat belts, sleeping, breaking problem, tire problem, animal entrance and technical problem. Hence to prevent and reduce the occurrence of accident on the expressway the researcher recommended some possible measures. These measures are appropriate driving training program, education, making policy or legislation and enforcement have been forwarded for the responsible government and road users.