Section 4 Case Studies
  Discussed on the following pages are examples of accident patterns I - III. In order to clarify the relationship between human and road-environment factors, behavior, perception, and judgment of the parties to the accident are organized in chronological order, using a variation-tree method².

  1) Pattern I. Accidents caused by, in addition to human error, such road environment factors as lack of traffic signs

  [Site of Accident]
  - An intersection of narrow and medium-wide roads in a residential area
  - Difficult to distinguish the main road, due to the lack of road markings and the similarity of road width
  - Light traffic on both roads
  - Visibility obstructed by surrounding concrete-block walls and hedges
    (with iron railing)
  - There is an entrance to a private house near the intersection.

Fig. 11 Accident Diagram

Photo 1: Site of accident seen from Vehicle A

Photo 2: Site of accident seen from Vehicle B

Fig. 12 Chronology of the Accident
    2) Pattern II: Accidents caused by perception errors such as overlooking an approaching vehicle

  [Site of Accident]
  - Intersection of two narrow roads in a residential area
  - Traffic signs, road markings and a traffic mirror installed
  - Difficult to confirm safety of the right side of Vehicle A, due to a concrete-block wall
  - There is a ditch on the other side of the wall

Fig. 13 Accident Diagram

Photo 3: Site of accident seen from Vehicle A

Photo 4: Site of accident seen from Vehicle B

Fig. 14 Chronology of the Accident
    3) Pattern III: Accidents caused by judgment errors such as erroneously assuming that the other vehicle would stop

  [Site of Accident]
  - Intersection of two narrow roads in a mixed residential/rice paddy area; very little traffic
  - Vehicle B's way went downhill for some distance to the intersection
  - The cyclist uses the road for traveling to and from school
  - No road markings or traffic signs are present, although there was a traffic mirror

Fig. 15 Accident Diagram

Photo 5: Site of accident seen from Vehicle A

Photo 6: Site of accident seen from Vehicle B

Fig. 16 Chronology of the Accident

UP

Back

Institute for Traffic Accident Research and Data Analysis (ITARDA)