EXPERIMENTAL INVESTIGATION OF THE SUPPORTING BEHAVIOUR OF CONCRETE SURFACINGS TAKING ACCOUNT OF THE COOPERATING EFFECT OF THE STALIZED ROADBASE

EXPERIMENTELLE UNTERSUCHUNG DES TRAGVERHALTENS VON BETONDECKEN UNTER BERUECKSICHTIGUNG DER MITTRAGENDEN WIRKUNG DER VERFESTIGTEN TRAGSCHICHT

KNOWLEDGE OF THE COEFFICIENT OF SUBGRADE REACTION OF THE LAYER SUPPORTING THE SURFACINGS IS NECESSARY FOR THE DESIGN OF CONCRETE PAVEMENTS. NOWADAYS ROADBASES ARE PLACED DIRECTLY BELOW THE SURFACINGS. THE COOPERATING FUNCTION OF THE ROADBASES IS USUALLY NOT CONSIDERED. HOWEVER, THEORETICAL INVESTIGATIONS SHOW THAT THERE IS LESS STRESS ON THE CONCRETE SURFACINGS IF THE ROADBASES ARE TAKEN INTO ACCOUNT. ON THE BASIS OF THESE STUDIES, LARGE SCALE TESTS ARE TO BE CARRIED OUT ON THE FOLLOWING: 21 CM OF CONCRETE SURFACING, UNREINFORCED, ON 20 CM OF CONCRETE ROADBASE, WITH A MODULUS OF DEFORMATION OF THE SOIL OF 1000 KP PER SQUARE CM AND 400 - 500 KP PER SQUARE CM, AND 14 CM OF CONTINUOUSLY REINFORCED SURFACING ON 25 M OF CONCRETE ROADBASE WITH A MODULUS OF DEFORMATION OF THE SOIL BETWEEN 400 AND 500 KP PER SQUARE CM. THE SINGLE OR DOUBLE LOADING WILL BE INTRODUCED BY MEANS OF A UNIVERSAL VIBRATION TESTING MACHINE WITH OR WITHOUT PHASE DISPLACEMENT. UP TO 2 MILLION ALTERNATING LOADS ARE ANTICIPATED AT 3 TO 4 LOADING POINTS.