Performance of shallow foundations on municipal waste landfills

加拿大有数万个封闭的城市垃圾填埋场，主要位于城市社区及其附近，这些土地大多仍未使用或仅用于非常低价值的目的。有机会探索将这些土地用于工业或市政基础设施，从而腾出其他土地用于高价值活动。因此，在评估在封闭的垃圾填埋场上建造基础设施的可能性时，有必要考虑填埋废物的特性。 目前，密闭式堆填区较高价值用途的技术和监管障碍与两类风险有关：i)“环境风险”；ii)“岩土风险”。与爆炸危险和垃圾填埋气中的污染物有关的环境风险是显而易见的。在不消除对环境风险的担忧的情况下，这项建议的目的是考虑--假设现代工程屏障可以用来缓解环境风险--对更高价值的后处理用途的限制将越来越多地转向与废物填充材料的岩土或机械特性以及由此产生的利用废物建造的设施的性能相关的风险。 有几个重要的基础设施是由废弃的浅基础支撑的例子。例如，德国卡尔斯鲁厄垃圾填埋场上的3台风力涡轮机，由大型环形基础支撑，经历了显著的垂直沉降，差异沉降或倾斜的问题很小，尽管设计效率可能提高的程度尚不清楚。 许多研究人员已经研究了堆填区的整体沉降，但到目前为止，研究还没有涉及差异沉降的规模和模式以及由此对浅基础的影响。这项研究将纳入实地和实验室测试，旨在为工程设计者提供更好的基础，以便在此基础上设计填埋废物的设施，以期减少不确定性和相关的过度设计。

There are tens of thousands of closed municipal landfills in Canada, primarily in and near urban communities, and these lands, for the most part, remain unused or used only for very low-value purposes. There is an opportunity to explore the use of these lands for industrial or municipal infrastructure, thus freeing up other land for high value activities. It is therefore necessary to consider the properties of landfilled waste when evaluating the possibility that infrastructure may be constructed on closed landfills. At present, technical and regulatory barriers to higher-value uses of closed landfill sites are associated with two categories of risk, which may be termed: i) "Environmental Risk"; and ii) "Geotechnical Risk". There is evident environmental risk associated with explosion hazard as well as contaminants in landfill gas. Without dismissing concerns regarding Environmental Risks, the intent of this proposal is to consider that -assuming modern engineered barriers can be used to mitigate environmental risk - the limitations to higher-value after-uses would increasingly switch toward the risk associated with the geotechnical or mechanical properties of the waste fill material and the consequent performance of facilities constructed on waste. There are several examples of significant infrastructure supported by shallow foundations on waste. For example, 3 wind turbines supported by large ring footings on a landfill in Karlsruhe Germany have undergone significant vertical settlement with only minimal problems with differential settlement or tilting, although the degree to which the designs might have been made more efficient is not known. A number of researchers have studied the overall settlement of landfills, however studies to date have not addressed the scale and patterns of differential settlement and the consequent effect on shallow foundations. The research will incorporate field and laboratory tests intended to provide engineering designers with an enhanced basis upon which to design facilities on landfilled waste, with the view to reducing the level of uncertainty and associated overdesign.