The analysis of behavioral sequences involved in accidents is
one of the most promising methods leading to safety improvements.
In this study attention was centered on accidents attributable to
lane-changing maneuvers on the Tomei Expressway. It contained two
phases, an analysis of the cause-and-effect relationships of
accidents and the measurement of interaction situations in real
traffic.
In the first phase, a chain of events (detection of other
vehicles, decision, action, vehicle response, etc.) until collision
was developed for each reported accident on the Tomei Expressway by
examining the complete accident reports with narratives. By
integrating each chain, a logical diagram tracing all events was
constructed, and causes and characteristics of accidents related to
lane-changing maneuvers were examined.
In the second phase, in the observation of lane-changing
maneuvers in traffic on the Tomei Expressway, measurements were
made of motion and positional parameters involved in two-vehicle
interaction.