Performance testing of strained BGM welds

Geomembranes are essential for liquid containment, with bituminous geomembranes (BGMs) benefiting from a unique composition of polymer-modified bitumen and polyester geotextile. This study examines the strain response of BGM liner systems, focusing on weld seams, which are typically the weakest points. Through uni-axial creep and multi-axial burst (MAB) testing, the viscoelastic behavior of BGM welds was investigated. Creep tests showed no rupture at 30% strain and showed substantial stress relaxation. MAB tests demonstrated that both BGM material and welds could handle strains nearing 30% before ultimate rupture suggesting BGMs have good strain tolerance compared to other geomembranes. This research provides insights into BGM performance under stress, guiding design and installation in containment applications. Further research is recommended to refine stress calculations for composite materials like BGMs and to broaden the comparative analysis with other geomembrane types.