IMPACT TESTS ON REINFORCED CONCRETE PILES

AUFPRALLVERSUCHE MIT STAHLBETONPFAEHLEN

IN ORDER TO ESTABLISH AN ECONOMIC DESIGN METHOD FOR REINFORCED CONCRETE PILES WHICH AS BRIDGE SUPPORTS IN ROAD TUNNELS ARE IN DANGER OF BEING COLLIDED WITH BY VEHICLES RUNNING OFF THE ROAD, REALISTIC IMPACT TESTS ARE NECESSARY. FOR THESE AN IMPACT TEST FACILITY IS REQUIRED, AND THIS IS BEING BUILT ON LAND BELONGING TO THE GERMAN RAILWAYS AT ROSENHEIM. THE MOST IMPORTANT PARTS OF THE INSTALLATION ARE: THE STEEL STRUCTURE WHICH SERVES AS THE UPPER FIXING POINT OF THE PILE TO BE TESTED, IS ANCHORED TO THE STEAM LOCOMOTIVE, AND ENABLES MEASUREMENTS TO BE MADE OF THE IMPACT FORCES WHICH OCCUR AT THIS SUPPORTING POINT; A CABLE TRAIN DEVICE WHICH, LINKED WITH THE TRAIN AND NOTCHING ROLLERS, ALLOWS THE TEST VEHICLE TO IMPACT THE REINFORCED CONCRETE PILE AT THE DESIRED SPEED. 6 - 6 IMPACT TESTS UNDER VARYING CONDITIONS ARE ANTICIPATED. THE TESTS PLANNED EXTEND TO MEASUREMENTS OF STRAIN TO DETERMINE THE TEMPORAL COURSE OF THE IMPACT FORCES AT THE UPPER SUPPORTING POINT AND AT THE IMPACT POINT WHICH IS ABOUT 1.2 M ABOVE THE TOP EDGE OF THE RAIL, AND TO THE DETERMINATION OF BENDING MOMENTS IN A NUMBER OF CROSS-SECTIONS, PARTICULARLY IN THE SOIL AREA. MOREOVER INDUCTIVE LOOP SENSORS ARE TO BE USED TO DETERMINE THE DEFLECTIONS IN THE DIRECTION OF IMPACT IN AS MANY CROSS-SECTIONS AS POSSIBLE, AND MEASURING DEVICES ARE TO BE USED TO DETERMINE THE COURSE OF HORIZONTAL SOIL PRESSURES.