1D – Free Swell Test

The one-dimensional free swell test (ASTM D4546-14) is used to measure the free 1-D swell of cohesive soils using a conventional consolidation cell setup. Tests are performed on a compacted specimen in the consolidation cell and then the seating pressure of 1 kPa is applied. During the swell test, the compacted specimen is fully submerged with distilled water in the consolidation cell with a seating load of 1 kPa until the swelling is completed. Results from the test predict the swell characteristics of the soils.

The 1-D free swell test (ASTM D4546-14) is routinely employed in geotechnical engineering practice to assess quantitatively the swelling potential of undisturbed or remolded clays, and to guide the design of surface structures on these soils.

• Common Dimensions of Soil Specimens: H 1-inch x D 2.5 inch
• Seating Pressure: 1 kPa (20lbf/ft 2 )
• Typical deformation measurement time: 24 to 72 hours (sometimes a few weeks)

The free 1-D swell of cohesive soils

• Design and analysis of soft ground
• Design of road pavement for expansive soils

• Pedarla, Aravind, Anand J. Puppala, Laureano R. Hoyos, and Bhaskar Chittoori. “Evaluation of swell behavior of expansive clays from internal specific surface and pore size distribution.” Journal of Geotechnical and Geoenvironmental Engineering142, no. 2 (2016): 04015080.