Long term performance of bituminous and modern geomembrane liners with high interface shear strength

土工合成屏障被广泛应用于垃圾填埋场等地质环境工程和许多采矿应用中。这些巨型填充物/池塘(有时为1000万平方米)现在需要在土工合成衬里上建造。衬里系统通常在低渗透性土层上覆盖一层聚合物土工膜，以起到阻止污染物迁移到周围环境中的屏障的作用。 除了由于安装不当或突然施加外力而导致的灾难性故障外，这些土工膜在短期内通常是坚固的。然而，土工膜可能会因其缓慢的老化过程(即降解)而长期失效，从而导致污染物向环境中迁移和/或边坡衬垫的不稳定。任何一项都将涉及随后的重大补救费用。为了确保我们的环境在矿物开采和废物处理作业中得到保护，土工膜具有足够和已知的使用寿命是至关重要的。今天，许多创新的土工膜被用于设计垃圾填埋场和采矿设施，但很少或根本没有关于其耐久性的辅助研究。因此，在战略上需要了解和评估这些土工膜的寿命，以最大限度地减少在安全壳设施的设计寿命期间(几十年到几个世纪)与环境的负面相互作用。 拟议的研究将利用皇后学院独特的屏障系统评估基础设施，进行新的最先进的研究，以检验具有高界面剪切性能的现代聚乙烯和沥青土工膜的化学耐久性。这些土工膜的性能将首次在剪切下进行进一步测试，以研究老化对垃圾填埋场和采矿设施边坡衬砌界面剪切强度的影响。此外，将利用在试验过程中收集的数据进行数值模拟，以首次检验土工膜老化对边坡衬砌岩土稳定性的影响。 这项研究旨在对目前市场上提供的土工膜的性能建立一个基于证据的严格理解，并将在未来几十年/几个世纪依赖于保护我们的环境。这一理解将有利于加拿大土工合成社区(顾问、制造商、监管机构)实现屏障系统的更好设计，并通过保护我们的地表水和地下水免受污染，同时建立最有效的资源利用和税收收入，使公众受益。该项目将培养3名博士、2名硕士和4名本科生，这些学生将掌握进行土工合成衬里性能评估的独特实验和前沿分析技术的技能，他们将把自己的独特知识和技能带到工业界和学术界。

Geosynthetic barriers are widely used in geoenvironmental projects such as landfills and many mining applications. These mega fills/ponds (sometimes >10M m2) are now required to be constructed on geosynthetic liners. The liner systems often comprise a polymeric geomembrane over a low permeability soil layer to function as a barrier against contaminant migration into the surrounding environment. Aside from catastrophic failures due to poor installation or sudden application of external forces, these geomembranes are typically robust in the short term. However, geomembranes can fail in long term due to their slow aging process (i.e. degradation) resulting in contaminant migration to the environment and/or the instability of the side slope liner. Either would involve major subsequent remediation costs. To ensure that our environment is protected during mineral extraction and waste disposal operations, it is critical that geomembranes have an adequate and known service life. Today, many innovative geomembranes are offered for designing landfills and mining facilities with little to no supporting research on their durability. Thus, there is a strategic need to understand and evaluate the longevity of these geomembranes to minimize negative interactions with the environment during the design life of the containment facility (several decades to centuries). The proposed research will capitalize on the unique barrier system evaluation infrastructure available at Queen's to conduct novel state of the art research examining the chemical durability of modern polyethylene and bituminous geomembranes with high interface shear properties. For the first time, the performance of these geomembranes will be further examined under shear to investigate the effect of aging on the interface shear strength of the liner on the side slopes of landfill and mining facilities. Furthermore, numerical modeling will be used with the data collected during the experimental program to examine, for the first time, the effect of aging of the geomembrane on the geotechnical stability of the side slope liners. This research aims to establish an evidence based rigorous understanding of the performance of geomembranes offered today in the market and will be relied on to protect our environment for the coming decades/centuries. This understanding will benefit the Canadian geosynthetic community (consultants, manufacturers, regulators) in achieving better design for barrier systems, and the public by protecting our surface and ground waters against contamination while establishing the most efficient use of resources and tax dollars. This program will train 3 PhD, 2 MSc, and 4 undergraduate students that will involve skills in conducting unique experiments and leading-edge analysis techniques in performance evaluation of geosynthetic liners, who will carry their unique knowledge and skills to industry and academia.