Effect of time and temperature on critical geosystems

垃圾填埋场屏障系统通常包括一个渗滤液收集系统（收集污染水）和一个复合衬垫。复合衬垫通常包括1.5-2.5毫米厚的聚合物（土工膜，GM）衬垫在土工合成粘土衬垫（GCL）上，其中包括一层薄的膨润土粘土，该膨润土粘土在与水接触时膨胀，并大大减少了土工膜孔的泄漏。这些地质系统通常预计将运行数十年至数百年。然而，除非我们改变设计和/或操作，否则其中一些系统不太可能具有理想的长期性能（例如，渗滤液收集系统可能由于生物引起的堵塞而堵塞）。这项研究将产生一个独特的校准计算机模型，可用于设计渗滤液收集系统，以提供所需的长期性能。通过建模、实验室和实地研究来发现和解释潜在的机制，一个简单的设计程序将被开发出来供工程师使用。我对转基因材料的研究将首次明确量化转基因材料厚度对其长期性能的影响，而与不同转基因配方相关的研究预计将产生比目前所需的更复杂的规格要求。它还将提供首次预测长期GM性能在现实暴露条件下的单和双衬垫系统。最近人们认识到，某些堆填区的操作模式会导致衬垫温度升高，从而使衬垫的寿命缩短至几十年甚至更短。在这些情况下，将研究控制衬垫温度的技术。最后，将研究控制全氟化学品逸出的现代屏障的有效性。这项研究将使加拿大和国际设计顾问、监管机构、垃圾填埋场运营商和公众受益，他们都将能够更加依赖这些地理系统。该研究将为9名博士生提供培训。

Landfill barrier systems typically involve a leachate collection system (to collect contaminated water) and a composite liner. The composite liner often includes a 1.5-2.5mm thick polymer (geomembrane, GM) liner over a geosynthetic clay liner (GCL) which includes a thin layer of bentonite clay which swells on contact with water and substantially reduces leakage through holes in the geomembrane. These geo-systems are typically expected to function for many decades to centuries. However, unless we change our designs and/or operations, some of these systems are unlikely to have the desired long-term performance (for example, a leachate collection system can block-up due to biologically induced clogging). This research will result in a unique calibrated computer model that can be used in design of leachate collection systems that will provide the required long-term performance. Following modelling, lab and field studies to discover and explain the underlying mechanisms, a simple design procedure will be developed for use by engineers. My research into GMs will provide the first clear quantification of the effect of GM thickness on their long-term performance while research relating to different GM formulations is expected to result in more sophisticated specification requirements than are currently required. It will also provide the first ever projections of long-term GM performance under realistic exposure conditions for both single and double liner systems. It has recently been recognised that some modes of landfill operations result in liner temperatures that may reduce their life to a few decades or even less. Techniques for controlling liner temperatures for these situations will be investigated. Finally, the effectiveness of modern barriers for controlling the escape of perfluorinated chemicals will be investigated. This research will benefit Canadian and international design consultants and regulators, landfill operators and the public who will all be able to place greater reliance on these geo-systems. The research will provide training to 9 PhD students.