Limiting local tensions in landfill geomembranes

加拿大每年产生约3 000万吨固体废物（加拿大统计局，2005年）。 尽管减少、再利用和回收废物的努力取得了切实成果，但在可预见的未来，加拿大人将继续需要垃圾填埋场来安全处置城市和工业固体废物。 屏障系统由覆盖在低渗透性粘土上的土工膜（薄塑料片）组成，用于衬在垃圾填埋场的底部。 屏障系统的目的是通过最大限度地减少有毒化学品（如重金属和碳氢化合物）泄漏到周围环境中来防止地下水污染。 长效土工膜是确保充分长期环境保护的关键。 当埋在大量废物下面时，土工膜的物理反应直接影响它的持续时间，特别是覆盖在上面的砾石颗粒可能在土工膜中产生的局部张力。 将设计和进行物理实验，并将开发和应用数值分析，以防止在垃圾填埋场土工膜的局部张力土工膜破裂。 由于局部张力取决于塑料薄膜，周围的土壤，废物的量，温度和时间，拟议的研究联合收割机必要的元素，从岩土工程，土工合成材料工程和工程力学。 这项研究建立在申请人解决涉及用于环境应用的掩埋聚合物结构问题的良好记录之上。 四名博士生和五名硕士生将在五年内接受高级培训。 由于垃圾填埋场屏障系统过早失效可能会导致地下水污染造成长期的社会、环境和可能的健康影响，拟议的研究将改善土工膜衬垫的长期物理性能，并将使加拿大人受益，因为垃圾填埋场提供了更大的长期环境保护。

Around 30 million tonnes of solid waste is generated each year in Canada (StatsCan 2005). Despite tangible results from efforts to reduce, reuse and recycle waste, Canadians will continue to require landfills for the safe disposal of municipal and industrial solid waste for the foreseeable future. Barrier systems comprised of a geomembrane (a thin plastic sheet) overlying low permeability clay are used to line the bottom of landfills. The purpose of the barrier system is to prevent groundwater contamination by minimizing the escape of toxic chemicals (like heavy metals and hydrocarbons) into the surrounding environment. A long-lasting geomembrane is key to ensuring adequate long-term environmental protection. The physical response of the geomembrane when buried beneath large amounts of waste directly impacts how long it will last, especially the local tensions that can develop in the geomembrane from overlying gravel particles. Physical experiments will be devised and conducted, and numerical analyses will be developed and applied to prevent geomembrane rupture from local tensions in landfill geomembranes. As local tensions depend on the plastic membrane, the surrounding soil, the amount of waste, temperature and time, the proposed studies combine necessary elements from geotechnical engineering, geosynthetics engineering and engineering mechanics. This research builds on the applicant's strong track record of solving problems involving buried polymer structures for use in environmental applications. Four Doctoral and five Masters students will receive advanced training over five years. As premature failure of landfill barrier systems may result in substantial long-term social, environmental and possible health impacts as a result of groundwater contamination, the proposed research will improve the long-term physical performance of geomembrane liners, and will benefit Canadians with landfills that provide greater long-term environmental protection.