Gokongwei College of Engineering
Civil Engineering Department
Experiment No. 1
Vane Shear Test in Cohesive Soil
Dela Peña, Analyn A.
Engr. Irene Ubay
October 8, 2012
Vane shear test is used to measure the shear strength of a soil. It also estimated and measured the fully saturated clay’s undrained shear strength without derangement in the specimen. This test can be conducted in field and laboratory however, in laboratory can only execute the experiment with low shear strength (0.3 kg/cm2) for which unconfined test cannot be performed. The test apparatus are composed of 3 different diameters of 4-blade stainless vane that is attached in a steel rod that pushed vertically in the soil. The pocket value that can get in small vane should multiply by two however, the value can get in large vane should divide by two and the value that can get in medium vane is as it is. The test is performed by pushing the vane vertically in the soil and rotated it clockwise from the surface to determine the torsional force. The soil will resist the rotation of the vane and its resistance is the force of soil that causes the cylindrical area to be sheared by the vane. When the rotation of the vane is continues it means that the soil fails in shear and it is normal that the rotation is continued after measuring the shear strength.
VANE| | DIAMETER(mm)| POCKET VALUE VANE READING| MULTIPLIER| UNDRAINED (kPa)| SMALL| 1| 16| 0.00| 2| 0|
| 2| | 0.20| | 0.40|
| 3| | 0.20| | 0.40|
MEDIUM| 1| 20| 0.60| 1| 0.6|
| 2| | 0.50| | 0.5|
| 3| | 0.60| | 0.6|
LARGE| 1| 25.4| 0.90| 0.5| 4.5|
| 2| | 1.50| | 7.5|
| 3| | 1.30| | 6.5|
CONTAINER| MASS (g)| MASS + WET SOIL (g)| MASS + DRY SOIL (g)| MOISTURE CONTENT (g)| 1| 27.45| 36.03| 32.72|...