The volume change gauges are designed to measure changes in the volume of the specimen, measured in terms of the change in the volume of the cell, during a triaxial shear test. The apparatus consists of an outer acrylic tube and an inner graduated glass burette held between two aluminium blocks. Manifolds are provided to enable water to pass through the tubes during measurements or to go directly to the cell when no measurements are required.

The indicator is coloured paraffin (not supplied with the unit). The volume changes are measured by the downward movement of the paraffin/water interface in the tube burette. In the twin burette gauges, the manifolds allow the reversal of the flow of water, enabling continuous measurements when testing large-diameter samples. The gauges are designed for a working pressure of 1000 kPa.

Technical Volume Change Apparatus