A Gas Permeation Test to Assess in situ Quality of stiff Dual Geomembrane Seams

Abstract

To control in situ stiff geomembrane seams, carried out by means of the thermal hot dual wedge method, a non destructive test is suggested. It consists in pressurizing the gap between both welds by gas injection at a specific pressure and in monitoring the evolution of pressure over time. A permeation parameter can then be estimated under unsteady state conditions. The results show that the non destructive method here presented can reveal poor seams, undetectable by the pressurized dual seam method currently used in situ to assess the continuity of the seams. A new test can thus be included in the Construction Quality Control/Construction Quality Assurance activities to control seams quality, in pond applications where stiff geomembranes are placed.