ABSTRACT
This chapter demonstrates the influence of factors affecting the compaction process. These include material type, moisture content, size and type of roller (dynamic force is greater than static weight), loose depth being compacted, speed of roller (this may be as critical as moisture content, yet no controls are typically required), and number of passes. The lift thickness is influenced by the type and size of plant selected for use. Characteristics of the typical heavy compaction rollers and their uses in various material types are summarised. Laboratory testing variations for natural materials, and especially clays, show a target moisture content of ±2% OMC as not achievable in practice. Yet such specifications are commonly sighted. For end-product specifications, one must distinguish between a target and a recommendation to “optimise” reaching that target. Each soil type requires different equipment and processes. Three case studies are used to show laboratory and field test variation.
