MTS Model 286-30 Pore Pressure Intensifier - Manual (Page 23)

Pore Pressure System Operation Considerations
286.30 Pressure Intensifier Operation 23
Pore Pressure System Operation Considerations
Operating in Conjunction with a Confining Pressure System
Rock mechanics studies typically involve the use of a triaxial cell, a pore
pressure system and a confining pressure system. In such use, pore pressure is
applied to the flat, end surfaces of a cylindrical rock specimen while confining
pressure is applied to the curved, outer walls of the cylinder.
An impermeable jacket is usually placed around the curved outer cylinder wall to
act as a barrier between the open pores on this surface and the confining fluid,
thus preventing confining fluid flow into the specimen. In order to avoid
rupturing the impermeable jacket, pore fluid pressure should never be higher than
confining fluid pressure.