Triaxial Equipment for Permeability Testing with Hazardous and Toxic Permeants

The measurement of the hydraulic conductivity of finegrained soils utilizing hazardous and toxic permeants requires equipment speciffically designed and constructed for that purpose. Interaction between the pore fluids in the soils and the resulting soil response must be considered as well as the compatibility between the test equipment and the permeants. Further, a method of modeling the state of stress and permeation relative to field conditions must be incorporated in order to arrive at a system that can adequately determine the effects of hazardous and toxic permeants upon the hydraulic conductivity of fine-grained soils. The testing system developed for hydraulic conductivity testing with hazardous and toxic permeants has three major components. These are the control panel, the permeability board, and the triaxial cell. The necessary strength and compatibility was accomplished through the optimum use of stainless steel and aluminum to provide adequate rigidity while providing the ultimate compatibility through the use of Teflon® at any points in which the permeameter is in contact with the permeant. Equipment design and fabrication considerations in their special applicability for testing of hazardous and toxic permeants are discussed in this paper.