Leakage Control in Long-Duration Testing of Triaxial Specimens

Abstract

This note presents an inexpensive method of reducing the cell-fluid leakage in a long-duration consolidation/permeability test in a triaxial cell. It involves two membranes sealed with hose clamps over two O-rings and silicon grease at top cap and base, and a vegetable oil as cell fluid. It reduces leakage to an imperceptible level for a membrane immersion age of 7 days, beyond which small leakage appears and correction for this can be applied to the drainage volume measured in a consolidation stage. Careful selection of specimen diameter and minimum gradient combined with the inflow and outflow measurement as per ASTM D5084 minimizes the effect of leakage on permeability measured in the suggested setup.