Assessment of Single Vehicle-Tree Collisions “ An In-depth Analysis of Malaysian Crash Investigation Data

Assessment of Single Vehicle-Tree Collisions “ An In-depth Analysis of Malaysian Crash Investigation Data Z.A. Ahmad Noor Syukri, M.I. Mohd Hafzi, A. Aqbal Hafeez Vehicle Safety and Biomechanics Research Centre, Malaysian Institute of Road Safety Research, 43000 Kajang, Selangor, Malaysia Phone: +603 8924 9200 Fax: +603 8736 8685 E-mail: ansyukri@miros.gov.my Abstract- Fixed object collisions rank as one of the most severe road accidents. Of all fixed object collisions in Malaysia, tree was among the most common type of object being struck by vehicles. Previous studies on these types of crashes for Malaysian situation were mostly done using retrospective approach, by utilizing crash data from the police database. For the present study, a different approach was undertaken to better understand the scenario of vehicle-tree crashes. A sample of real-world vehicle-tree collisions from individual crash investigation data extracted from the MIROS Crash Analysis and Reconstruction database (MiCARS) was utilized. From MiCARS database, a total of 28 fatal single vehicle-tree collisions for year 2007-2010 were available for analysis. In this study, the integration of computerized analysis system, conventional hand calculation and photogrammetry method were carried out to estimate the important parameters of the crashes viz., vehicle travelling speed, tree profiles and occupants’ injury outcomes. Furthermore, this study highlights the contributory factors of the crashes which demonstrate complex human interaction with vehicle, road and environment, as well as other contributing factors for occupants’ injury outcomes in such investigated cases. Finally, to improve the situation, several countermeasures which range from design changes at the crash sites to tree shielding and removal techniques were recommended.