Mass Loss Measurement in Triaxial Permeameter Testing Review of Current Practices and Proposal for Advancement

Triaxial permeameter testing is a useful method for studying the mechanical behaviour of internally eroded specimens and involves four stages: reconstitution, consolidation, seepage, and axial compression. Under downward seepage, flow is introduced to the top of the specimen, erodes it, and leaves the specimen carrying eroded particles through the featured base pedestal designed to accommodate unimpeded outward movement of eroded particles. Careful collection and precise measurement of any mass loss is crucial for accurate void ratio estimation and characterization of erosion response. An internally unstable specimen reconstituted against featured boundaries experiences mass loss not only within but also out of the seepage window. This article reviews current mass loss measurement practices during the seepage stage, identifies challenges and the corresponding need for mass loss measurement throughout a triaxial permeameter test, and proposes a comprehensive method for measuring mass loss from the start of reconstitution to the end of axial compression.