LOAD TESTS ON FLEXIBLE SURFACES

ANALYSIS IS MADE OF SOME OF THE DATA OBTAINED FROM AN INVESTIGATION OF LOAD TESTS ON FLEXIBLE SURFACES CONDUCTED BY THE MICHIGAN STATE HIGHWAY DEPARTMENT IN 1937. THE FOLLOWING INDIVIDUAL FACTORS IN THE PROBLEM ARE DISCUSSED: (1) LOAD TEST RESULTS, (2) BEARING CAPACITY RELATIONS, (3) SOIL RESISTANCE COEFFICIENTS, (4) DETERMINATION OF YIELD VALUES BY TIME-SETTLEMENT RELATIONS, (5) ANALYSIS OF LOAD TESTS FOR A FLEXIBLE SURFACE, (6) ANALYSIS OF RESULTS BY THE YIELD VALUE METHOD, AND (7) CORRELATION OF FIELD AND LABORATORY TESTS. THE MOST IMPORTANT CONCLUSION OF IMMEDIATE PRACTICAL IMPORTANCE IS THAT RIGID BEARING AREAS PRODUCE SECONDARY DIMENSIONAL EFFECTS OF SUCH A HIGH ORDER OF MAGNITUDE THAT THEY MUST BE ELIMINATED TO OBTAIN RELIABLE RESULTS IN THE CASE OF FLEXIBLE PAVING SURFACES. IT IS, THEREFORE, RECOMMENDED THAT IMMEDIATE CONSIDERATION BE GIVEN TO THE DESIGN OF THE MOST PRACTICAL FLEXIBLE LOADING DEVICE. /AUTHOR/