초록 |
In general, the crash reduction effect of the rumble strip is reported to be about 30% in Korea, while it is about 40-60% in the United States. However, the effect is erroneously overestimated because the simple comparison was only made before and after the installation. Accordingly, this study will reassess the crash reduction effect of the rumble strip. The study will also examine the former's geometric characteristics as well as its effect on the causes of the crash. This study analyzed the crash effect while taking into consideration the changes in the horizontal and vertical alignment, including the width of pavement shoulders, using the crash data for two years before and after the installation of the rumble strip. The types of crash caused by the rumble strip were identified using the classification discriminant function. The crash effect on the rumble strip is estimated to be 28.3%, but the pure effect, with the exception of the effect by other elements, was analyzed to be 7.4%. For each expressway design element, the downhill section (2.0-3.0%), the section with less than 3,000 m and more than 10,000 m of the curve radius, and the section with less than 3.0 m of the pavement shoulder width were found to be effective in crash reduction. For each cause of crash, the rumble strip was analyzed to be effective in the reduction of crash caused by 'not keeping the safe distance', 'sleeping', 'negligence in keeping eyes forward', and 'excessive handle operation'. In particular, the rumble strip was analyzed and seen to be especially effective in preventing crash caused by 'not keeping a safe distance,' and 'sleeping'. The installation of the rumble strip was found to be effective in the prevention of crash caused by 'not keeping the safe distance' and 'sleeping'. The results of this study may thus be used in deciding the causes of crash and the installation location of the tailored rumble strip that would be suitable for the geometric characteristics of the roads. This study will also be helpful in the establishment of future traffic safety measures. |