DETERMINATION OF THE FRICTIONAL RESISTANCE OF CONCRETE ON GRAVEL BY MEANS OF LARGE-SCALE SHEAR TESTS UNDER VARIOUS SOIL PRESSURE CONDITIONS

ERMITTLUNG DES REIBUNGSWIDERSTANDES VON BETON AUF KIES DURCH GROSSSCHERVERSUCHE UNTER VERSCHIEDENEN BODENPRESSUNGEN

TESTS CARRIED OUT ON SUSPENSION BRIDGES HAVE SHOWN THAT VARIATIONS FROM THE FRICTIONAL COEFFICIENT (BASED ON THE CALCULATION) ARE PRODUCED BETWEEN THE FOUNDATIONS AND THE BUILDING GROUND. IN PARTICULAR, IT WAS FOUND THAT THE FRICTIONAL COEFFICIENT DECREASES WITH GREATER CONSOLIDATION. IN ORDER TO BE ABLE TO COMPARE THE FRICTIONAL COEFFICIENT (ASSUMED FOR THE CALCULATION OF THE BRIDGE) WITH THE ACTUAL VALUES FOUND, AND ALSO TO OBTAIN GENERALLY APPLICABLE RESULTS, THE LARGE SCALE SHEARING TESTS WERE CARRIED OUT WITHIN THE FRAMEWORK OF THE RESEARCH PROGRAMME. THE FRICTION RESISTANCES UNDER HIGH NORMAL STRESSES IN PARTICULAR SHOULD BE STUDIED WITH DIFFERENT DEGREES OF COMPACTION. THE NORMAL STRESS IN ONE REGION WAS BETWEEN 5 AND 100 TONS/M2, THE DEGREE OF COMPACTION VARIED BETWEEN 0.2 AND 1.0. IN ALL, 45 TESTS WERE PERFORMED. THE PROCEDURE AND EVALUATION OF THE TESTS ARE ILLUSTRATED IN THE RESEARCH REPORT OF JANUARY 1965 OF THE WATER TRAFFIC ENGINEERING, FOUNDATION AND SOIL MECHANICS, TECHNICAL UNIVERSITY AACHEN (SEE ALSO IRRD NO. 700957).