Compaction of earth materials for roadway construction is the primary activity to build embankment and to prepare subgrade, subbase, base, and stabilized layers of highways. Current standards of state highway agencies require contractors to build uniform material layers, without dependable means to continuously quantify and verify the degree of compaction. The implementation of intelligent compaction (IC) technology has the potential to provide continuous, real-time measurements for quality control/quality acceptance of compaction. Current IC technology depends solely on the roller measurement values (MVs), which represent a composite value of compacted layers within a zone of influence, approximately 3.3 feet in depth. MVs are influenced by variation in layer thickness, moisture, layer stiffness, machine vibration, drum-soil interaction, etc. The inability to associate the contribution of these variables on MVs is an obstacle for implementing IC technology in construction acceptance.
NCHRP Report 933, Evaluating Mechanical Properties of Earth Material during Intelligent Compaction should be of immediate use to those responsible for the quality management of geomaterial compaction as it addresses this obstacle and helps to provide a better understanding of the mechanical properties of earth materials governing IC. The study entailed a literature review, development of finite element models to be used for geomaterial compaction response simulation, laboratory and field tests for model validation, and development of proposed specifications.