CROSS-MEDIAN CRASHES

ALTHOUGH CROSS-MEDIAN CRASHES ARE RARE EVENTS, EVIDENCE HAS SHOWN THAT THIS TYPE OF CRASH TENDS TO BE SEVERE IN TERMS OF VEHICULAR DAMAGES AND EXTENT OF PERSONAL INJURIES. SINCE THESE CRASHES OCCUR SO INFREQUENTLY, DETAILED STUDY EXCLUSIVELY UTILIZING EMPIRICAL TECHNIQUES IS TIME-CONSUMING AND EXPENSIVE, SO COMPUTER SIMULATION WAS SELECTED FOR INVESTIGATING THIS PROBLEM. THE SIMULATON MODEL DESCRIBED A 4-LANE EXPRESSWAY IN WHICH CARS WERE RANDOMLY RELEASED TO CROSS THE MEDIAN AT A RIGHT ANGLE AND AT A CONSTANT SPEED. NO PROVISION WAS MADE FOR THE DRIVER TO BRAKE OR REGAIN CONTROL OF THE CAR. OPPOSING VEHICLES WERE GENERATED BY THE NEGATIVE EXPONENTIAL DISTRIBUTION. THE EFFECTS OF THE FOLLOWING VARIABLES ON PROBABILITY OF CRASH AND AVERAGE IMPACT SPEED WERE STUDIED: LANE VOLUME, SPEED OF OPPOSING VEHICLES, SPEED OF CROSSING VEHICLES, MEDIAN WIDTH, PERCEPTION-REACTION TIME, AND SKID RESISTANCE. IT WAS FOUND THAT, FOR THOSE VEHICLES CROSSING THE MEDIAN, THE PROBABILITY OF A CRASH WAS SIGNIFICANTLY INCREASED BY (A) INCREASE IN LANE VOLUME, (B) DECREASE IN MEDIAN WIDTH, (C) DECREASE IN VEHICLE SPEEDS AND (D) INCREASE IN REACTION TIME. SKID RESISTANCE WAS OF LEAST IMPORTANCE IN REDUCING CRASH PROBABILITIES. IT WAS FURTHER FOUND THAT AVERAGE IMPACT SPEED WAS SIGNIFICANTLY INCREASED BY (A) INCREASE IN VEHICLE SPEEDS (B) INCREASE IN REACTION TIME, AND (C) DECREASE IN MEDIAN WIDTH. IMPACT SPEED WAS LITTLE INFLUENCED BY SKID RESISTANCE AND LANE VOLUME. /AUTHOR/

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 44-53
  • Monograph Title: Highway safety improvements
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00221247
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Jun 11 1971 12:00AM