A STUDY ON MOTORCYCLISTS HEAD INJURIES IN CAR-MOTORCYCLE ACCIDENTS BASED ON REAL-WORLD DATA AND ACCIDENT RECONSTRUCTION

Accident data had shown that as one of the most vulnerable road users, the risk of motorcyclist casualties due to head injuries is extremely high in motorcycle accidents. The objective of this study was to analyze motorcyclist head injury based on epidemiological statistical analysis and car-motorcycle accident reconstruction using real world accident data, and obtain a comprehensive understanding about safety effects of helmets on motorcyclists head injury. In epidemiological data analysis of this study, odds ratios (ORs) was applied to identify differences in injuries between helmeted and unhelmeted motorcyclists. Two vehicle-motorcycle collisions with detailed information were reconstructed by using PC-Crash simulation and MADYMO reconstruction. Furthermore, the head injury reconstruction using MADYMO outputs as boundary conditions was accomplished and analyzed with respect to 1st principal strain, Von Mises stress, coup pressure, countercoup pressure at the cerebrum. The results indicated that unhelmeted motorcyclists were more likely to suffer head injury, serious and fatal injury, and tend to take equal responsibility or more. 1st principal strain was reduced from 0.44 to 0.25 for Case 1, and from 0.16 to 0.10 for case 2 when including a helmet. Von Mises stress were reduced from 30.37 kpa to 19.51 kpa for Case 1 and from 3.42 kpa to 3.03 kpa for case when including a helmet, which meant a reduction of the risk of concussion. But the motorcyclist in Case 2 experienced a lower percentage increase in coup pressure and countercoup pressure. This study provided comprehensive knowledge on motorcyclists head injuries and the effectiveness of helmets as well as contributing to develop the injury prevention measures and protection devices of motorcyclists.