The oedometer is an instrument used to perform the oedometer test (or consolidation test), which measures the compressibility and consolidation rate of a saturated fine-grained soil, typically clay.

The test is conducted by applying progressive vertical loads to a cylindrical soil sample inside a cell that prevents any lateral expansion (one-dimensional deformation condition). The change in thickness of the sample over time is observed at each load increment.

Main objectives:

• Calculate the coefficient of volume compressibility (Mv)
• Determine the consolidation coefficient (cv)
• Estimate settlements over time for foundations on compressible soils

Types of oedometer:

• Mechanical (manual data reading)
• Digital or automatic (continuous data recording)