In recent years the number of applications in zone of high seismicity has increased. Conse-quently, the need for geomembranes with high interface shear strength under dynamic loads has increased. Due to their nature, combining a geotextile for strength and puncture resistance and bitumen for the water-proofing low permeability characteristics, bituminous geomembranes (BGM) have shown to possess high interface shear resistance under seismic loads. The paper discusses the reasons for the strong resistance of BGM, namely the ability to deform and espouse the tortuous path along the interface between soil particles without punctures due to the viscous-elasticity of BGM which allows for the development of a strong in-terlocking between soil particles and the bituminous geomembrane yielding high values of interface shear strength.
This paper presents two cases studies. In the first case, the paper reports the use of Coletanche in a project in a highly seismic zone where the bituminous geomembrane is used as part of a leak collection system under buried concrete reservoirs. Laboratory testing was performed to establish the geomechanical proper-ties required for use in a dynamic finite element analysis of the reservoir subjected to seismic loading.
The second case study discusses the performance of a tailings dam lined on its bituminous geomembrane in Peru in Cerro Lindo subjected to a large seismic event. Results are presented of the survey performed by a consultant on the behavior of the dam and, in particular, of the BGM following an earthquake of magni-tude of 8.1 in Chincha close to the site.