ANCIENT DRUMLIN HILLSLOPES AND MODERN EMBANKMENT DAMS / IMPLICATIONS FOR PREFERENTIAL SEEPAGE AND STABILITY IN ENGINEERING PRACTICE.

该建议的科学价值在于对从两个地点获得的新现场数据进行了新颖的比较，这两个地点都有广泛的现有数据集，一个是最近在冰川丘上的一个大钻孔（在北爱尔兰的拉夫布里克兰），另一个是加拿大的一个大型现代土坝（WAC Bennett大坝，不列颠哥伦比亚省），在一次天坑事件后的缺陷调查中发现了优先流。在爱尔兰北部的一个大的凹地切割处测量的不寻常的地下水状况的数据表明，优先的渗流和内部侵蚀正在发生。最近对加拿大一座土坝堆芯的现场数据进行了详细分析，并对土壤样品进行了相应的实验室渗透仪测试，所获得的经验也表明，渗水引起了内部侵蚀的发生。比较英国一个古老的土坡和加拿大一个现代土坝的目的是寻找与潜在的内部不稳定有关的土壤级配的共同特征和空间变化以及对渗漏的响应。通过对一个相对年轻的土坝（大约35年）重建的土坝进行性能监测和实验室测试的一项宝贵的长期研究，以及这些发现的含义，英国从详细检查加拿大数据中获得的知识和见解，有助于解释一个相对较短的在一个古老山坡（超过10,000年）未受干扰的土坝的现场观察记录。因此，该建议有一个明确的重点：辨别受地下水渗流影响的冰川坡地的渗流、内部侵蚀和稳定性方面的长期行为特征，这些特征对土坝坡地核心的行为有影响。预计对两个地点的土壤进行仔细评估，并考虑各自的渗流机制，将为每个小组正在进行的研究工作提供巨大价值的“案例研究”比较，并将重要的大学-工业研究成果传播给英国大学部门。

The scientific merit of the proposal rests on a novel comparison of new field data being acquired from two sites both with an extensive existing data set, one a recent large cutting in a drumlin in glacial till (at Loughbrickland, N. Ireland) and the other a large modern earth dam in Canada (the WAC Bennett Dam, British Columbia) where preferential flow has been found as part of a deficiency investigation following a sinkhole incident.Data from the measurement of the unusual groundwater regime of a large cutting in the lodgement till in N Ireland suggests that preferential seepage flow and internal erosion is occurring. Recent experience gained in a detailed analysis of field data from the till core of an earth dam in Canada and companion laboratory permeameter testing of soil samples also indicates that seepage induced internal erosion occurred. The objective of comparing an ancient till hillslope in the UK with a modern earth dam in Canada is to look for common features and spatial variations in the soil gradations and response to seepage that relate to the potential for internal instability. The benefit to the UK from examining in detail the Canadian data accrues by transferring the knowledge and insights obtained from this an invaluable long-term study of performance monitoring and laboratory testing of the reconstituted tills of a relatively young earth dam (approximately 35 years), and the implications of those finding, to aid the interpretation of a relatively short record of field observations in undisturbed tills of an ancient hillslope (over 10,000 years old). Accordingly, the proposal has a clear focus:To discern attributes of the long-term behaviour with respect to seepage, internal erosion and stability, of glacial tills, subject to groundwater seepage, that have implications for the behaviour of till cores in earth dams.It is expected that careful evaluation of the soils at the two sites, and consideration of the respective seepage regimes, will deliver a 'case-study' comparison of tremendous value to ongoing research efforts of each group, and a dissemination of significant university-industry research findings to the UK university sector.