STUDY OF THE BEGINNING OF SKID MARKS UNDER VARIOUS CONDITIONS AND ON VARIOUS ROAD SURFACINGS

UNTERSUCHUNG DES BEGINNS VON BREMSSPUREN UNTER VERSCHIEDENEN BEDINGUNGEN AUF VERSCHIEDENEN FAHRBAHNBELAEGEN

IF DRIVING SPEED IS TO BE CALCULATED FROM SKID MARKS, THE QUESTION ARISES AS TO HOW THE BEGINNING OF THE MARK CAN BE ASSESSED. THE MARK COULD START IN AN AREA WHERE THE WHEEL IS STILL REVOLVING (THRESHOLD PROCESS), OR ALTERNATIVELY NOT UNTIL THE WHEEL IS LOCKED AND PULLED ACROSS THE ROAD. THE AIM OF THIS RESEARCH PROJECT IS TO DETERMINE THE ROAD SURFACINGS ON WHICH THE SKID MARK BEGINS WHEN THE WHEEL IS LOCKED, AND THOSE ON WHICH THE SKID MARK BEGINS IN THE THRESHOLD PROCESS. THE PROCESS OF HEATING, THE TEMPERATURE OF THE SURFACING AND THE TYPE OF SURFACING, AND SOMETIMES ALSO THE COMPOSITION OF THE TYRE RUBBER ALL PLAY A PART. THE STUDIES ARE TO BE CARRIED OUT WITH THE STUTTGART FRICTION METER. THE PARAMETERS BEING CONSIDERED ARE ROAD, DRIVING SPEED, TEMPERATURE, TYRE AND WHEEL LOAD.