As high earth dams, deep compacted highway embankments, and other thick compacted fills become more common, it is imperative that engineers consider and control the potential for wetting-induced collapse in compacted fills. Problems associated with collapse settlements in compacted fills include damage to structures and foundations placed on fills; cracking and slope failure within fills; damage to pavements and subgrades placed on highway embankments; piping, seepage losses, and failure in earth dams; as well as distress or failure of underground utilities. In contrast to naturally deposited soils, whose potential for collapse is determined by natural processes, an engineer can control the potential for collapse in a compacted fill during the placement process. In this paper, a synthesis is presented of the writers' experience, research, and extensive literature review of the mechanisms causing collapse, soil parameters affecting the occurrence and magnitude of collapse, and case histories in which substantial damage from collapse settlements has occurred.
