Comparison of Laboratory and Field Test Results for Granular Bases

The performance of a flexible pavement depends, to a large extent, on the mechanical characteristics such as stiffness and deformation resistance of its base layer. The laboratory static triaxial compression tests are common to estimate these mechanical characteristics. The resilient modulus tests are the other laboratory tests that are also gaining popularity. These laboratory tests are usually augmented with field tests such as the plate load, lightweight deflectometer or dynamic cone penetration tests. Since the methods of compaction and testing are different, one can anticipate that the mechanical characteristics measured in the laboratory and in the field are different even at the same moisture content and density. In this paper, the relationships among the laboratory and field mechanical characteristics of a common base with different fines contents and moisture contents are evaluated, reported and discussed.