Settlement is downward movement of soil or a structure as supporting material compresses or shifts under load.
Definition
Settlement describes downward movement that occurs when soil or other supporting material compresses or shifts under loading. The amount, timing, and distribution of movement depend on subsurface conditions, load, drainage, construction sequence, and other site factors. Engineers assess settlement for a defined project using investigation data, design criteria, and stated assumptions. A total movement estimate and a difference in movement between nearby points can have different implications for a structure or utility. Settlement is not the same as consolidation, although consolidation can be one cause of time-dependent settlement in saturated soils. It is also not automatically evidence of a failure: observed movement needs to be evaluated against project conditions and performance criteria. For firm owners, settlement assumptions affect geotechnical scope, foundation coordination, monitoring, and client communication. The ASCE resource provides a professional engineering context, while project-specific evaluation depends on site information.
How owners use it
- Discuss expected movement and its timing when coordinating geotechnical recommendations with foundation design.
- Track assumptions about loading, drainage, construction stages, and the investigation data supporting an estimate.
- Example: If a point moves from elevation 100.00 ft to 99.94 ft, the downward movement is 100.00 - 99.94 = 0.06 ft.
- Explain that observed movement requires interpretation against project criteria and conditions.
