Triaxial Compression Test - Soil Properties: Testing, Measurement, and Evaluation - page 353

(5) Prepare new specimens, and repeat the entire procedure at
other chamber pressures. If disturbed samples are used, the new
remolded specimens should have approximately the same unit
weight (within 1 to 2 lb/ft 3 ).

Data collected in the consolidated undrained triaxial compression test
should include the following:

DATA

[A] Specimen Data

Diameter or side of specimen, D 0 (in.)
Initial height of specimen, H 0 (in.)
Mass of specimen (g)
Water content data:
Mass of wet soil plus can (g)
Mass of dry soil plus can (g)
Mass of can (g)

[B] Triaxial Compression Data

Chamber pressure on test specimen,

σ 3 (psi)
Volume of water extruded from the specimen during consolidation,
Δ

V (i.e., volume of water accrued in burette) (in. 3 )
Rate of axial strain (in./min)
Deformation dial readings, H , and proving ring dial readings (in.)

Δ

Pore water pressure, (psi)

m

Note —These data are obtained for each of three or more specimens
tested at different chamber pressures.

[A] Specimen Parameters

CALCULATIONS

The specimen's initial area, volume, height-to-diameter ratio, wet unit
weight, water content, dry unit weight, and degree of saturation are all
calculated by methods described in previous chapters.

[B] Triaxial Compression (After Consolidation
in Triaxial Chamber)

The specimen's volume after consolidation ( V c ) can be obtained by sub-
tracting the volume of drainage out of the specimen during consolidation
(i.e., the volume of water accrued in the burette) ( V ) from the specimen's

Δ

original volume ( V 0 ). In equation form,

(22-2) V c V 0 ¢ V