EFFECT OF LEAF SPRING FRICTION OF LORRIES AND WHEEL LOAD FLUCTUATIONS CAUSED BY VIBRATING VEHICLE WHEELS ON ROAD STRESS

UNTERSUCHUNG DES EINFLUSSES DER BLATTFEDERREIBUNG VON LKW UND DER RADLASTSCHWANKUNGEN DURCH SPRINGENDE KFZ-RAEDER AUF DIE STRASSENBEANSPRUCHUNG

THE DYNAMIC VERTICAL LOAD OF A VEHICLE WHEEL IS RESPONSIBLE FOR ROAD STRESS, AND THIS IS PARTICULARLY GREAT WITH HEAVY LORRIES. AS THESE LORRIES ARE USUALLY EQUIPPED WITH LEAF SPRINGS THE WHEEL LOAD FLUCTUATION INCREASES AS A RESULT OF THE NATURAL FRICTION IN THE SPRINGS. THE SAME THING HAPPENS BECAUSE OF THE FREQUENTLY OBSERVED VIBRATION OF LORRY WHEELS ON THE CARRIAGEWAY. THESE CONDITIONS ARE TO BE SIMULATED DIGITALLY ON A COMPUTER BY MEANS OF A LORRY VIBRATION MODEL WHICH IS TO BE DEVELOPED. BEFOREHAND THE NATURAL FRICTION OF LEAF SPRINGS IN HEAVY LORRIES HAS TO BE MEASURED IN TEST RIG STUDIES. COMPUTER SIMULATION WILL TAKE PLACE FOR A JOURNEY ON NON-UNIFORM CARRIAGEWAY IRREGULARITIES. THE TIME FUNCTIONS OF THE WHEEL LOAD FLUCTUATION HAVE THEN TO BE EVALUATED IN ASSOCIATED STATISTICAL TESTS. BY VARIATION OF SUITABLE STRUCTURAL PARAMETERS OF A LORRY, A MAXIMUM REDUCTION IS TO BE BROUGHT ABOUT IN WHEEL LOAD FLUCTUATION.