PAVEMENT EVALUATION BY LOADING TESTS AT NAVAL AND MARINE CORPS AIR STATIONS

PAVEMENT EVALUATION DATA HAVE BEEN OBTAINED FOR 54 AIRFIELDS. THE TOTAL THICKNESSES OF THE FLEXIBLE TYPE PAVEMENTS ARE, WITH FEW EXCEPTIONS, BETWEEN THE LIMITS, 6 AND 12 INCHES, WHICH IS REMARKABLE IN VIEW OF THE FACT THAT THESE PAVEMENTS HAVE ACCOMMODATED PLANES HAVING WHEEL LOADS VARYING FROM 2,500 TO 60,000 LB FOR THE MOST PART WITHOUT SERIOUS DAMAGE TO THE PAVEMENTS AND WITHOUT EXCESSIVE MAINTENANCE COSTS. COMPLETE SUBGRADE DATA FOR BOTH ASPHALT SURFACED AND CONCRETE PAVEMENTS ARE PRESENTED FOR 32 AIRFIELDS, INDICATING THAT, UNDER THE PAVEMENTS THAT HAVE BEEN IN USE, THE IN-PLACE SUBGRADE MOISTURE CONTENT HAS BEEN LESS THAN THE IN-PLACE SUBGRADE DENSITY HAS BEEN GREATER FOR MOST SOIL TYPES THAN HAS BEEN GENERALLY ASSUMED IN DESIGN. TRIAXIAL SHEAR DATA OBTAINED WITH UNDISTURBED SUBGRADE SAMPLES PROVIDE A GOOD INDEX TO THE BEARING VALUE OF THE SUBGRADE. /AUTHOR/