STUDY OF STRESS ON ROADS CAUSED BY DYNAMIC LOADS

UNTERSUCHUNG DER FAHRBAHNBEANSPRUCHUNG DURCH DYNAMISCHE LASTEN

INFORMATION ON THE REQUIRED DESIGN OF A CARRIAGEWAY PAVEMENT IS BEING PROVIDED BY EXAMINATION OF THE CARRIAGEWAY ON A TEST RIG UNDER THE ACTION OF REALISTIC LOADS AND REALISTIC CLIMATIC CONDITIONS. TEST RIGS WHICH HAVE ALREADY BEEN BUILT OR HAVE BEEN PLANNED ARE BEING ANALYSED AND EVALUATED, AND A NEW KIND OF TEST RIG IS BEING DESIGNED FOR SIMULATION OF THE DYNAMIC CARRIAGEWAY LOADS CAUSED BY HEAVY VEHICLE TRAFFIC. IN THE PROPOSED RIG SINGLE AND TWIN-TYRED VEHICLE WHEELS ARE TESTED UNDER LOAD BY SERVOHYDRAULIC PULSES, CORRESPONDING TO ACTUAL WHEEL LOADS IN PRACTICE. THE PROCESSING OF REALISTIC CARRIAGEWAY IRREGULARITIES IN A COMPUTER ALLOWS FEED SIGNALS FOR THE PULSES TO BE DRAWN UP TAKING ACCOUNT OF THE VARIOUS VEHICLE TYPES, WHEEL LOAD SUSPENSIONS AND LOADING CONDITIONS, AND THE TIME-DEPENDENT ACTUAL IRREGULARITY OF THE EXPERIMENTAL SECTION OF ROAD. WITH REFERENCE TO THE PROPAGATION OF CARRIAGEWAY DEFORMATION, THE SIZE OF THE RIG IS SUCH THAT THE CARRIAGEWAY MAY BE SUBJECTED TO CLIMATIC CONDITIONS, BUT CAN BE BUILT WITH THE CONVENTIONAL MACHINES USED FOR ROAD CONSTRUCTION. THE STUDY ALSO COMPRISES THE STRENGTH CALCULATION OF THE TEST RIG MECHANICS AND AN ESTIMATION OF THE INVESTMENT AND OPERATING COSTS OF TWO TEST RIG DESIGNS.