9. CONCLUSIONS
    Close co-operation is needed between ground investigation contractors and consulting engineers to ensure that the geotechnical investigation work for the roads NDP can be satisfactorily carried out.
    Many soils are too easily rejected at selection / design stage. It is hoped that the proposed methods outlined in this paper will assist design engineers during scoping and specifying of ground investigation works for road projects.
    With modern instrumentation, monitoring of earthworks during construction is very straightforward. Pore water pressures, lateral and vertical movements can be easily measured and provide important feedback on the performance of the engineered soils.
    Phasing of the ground investigation works, particularly laboratory testing is considered vital so that the data can be properly evaluated.
    Disposal of ‘marginal’ soils will become increasingly difficult and more expensive as the waste licensing regulations are tightened. The advent of landfill tax in the UK has seen thorough examination of all soils for use in earthworks. This is likely to provide a similar incentive and challenge to geotechnical and civil engineers in Ireland in the coming years.
    A certification approach comparable with that outlined should be considered by the NRA for ground investigation and earthwork activities.
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中文译文
土方工程的地基勘察与施工
保罗•圭格利
爱尔兰岩土工程服务有限公司
摘    要：
当工程场地的处理面积有限且填方工程费用大量增加时，土方工程的地基勘察设计与施工已逐渐地变得重要。由于冰渍土以及含砾粘土的提出使土方工程地基勘察方法的纲要比传统的勘察方法更详细。 本文提出“岩土认证”观点以及对地基勘察与土方工程相结合的优点加以概要说明。论文网
1、引  言
许多爱尔兰含砾粘土的勘察与再利用评价使岩土工程师与道路工程师感到为难。这些冰渍土或含砾粘土主要表现为低可塑性而且还含有从粘土到漂石的不同粒径颗粒。大部分本地粘土与淤泥质土中包含不同比例的砂、砾石、卵石、漂石。颗粒级配控制着土体的行为，而且淤泥使土体性质易受天气变化影响。
土体含水量随着地区不同而不同，从都柏林硬灰黑含砾粘土的7%到中部、西南部或西北部浅灰色含砾粘土沉积物的20%-25%。含砾粘土吸附水的能力建立的较好但土方工程中计划的不恰当常导致其扩大。
一般来说，良好级配的土体对于含水量的轻微变大相当敏感，将导致强度下降或不适合用作工程回填土。许多含砾粘土（尤其中等淤泥质土或良好级配的砂）在选择阶段已经被筛除，但事实上它们能对压缩或强度起到特定的作用。
筛选过程应尽量使用本地土体或者回填区或路堤边性质相对较差的土体，通过仔细评价应加以应用。回填材料必须保持一定的含水量，既不能太湿导致土体不稳定也不能太干以致不能被充分压缩。
高含水量、低强度含砾粘土适用于低路堤回填（相当于2到2.5米的高度）但不适用于没有使用土工织布隔离与回填层的土方回填工程。因此，土方工程承包商充分认识土体的处理特性相当重要，因为许多工程都受到挖掘设备通行能力的影响。
2、传统地基勘察方法
对于道路工程来讲，地基勘察最基本目标是对土体适用性进行类似表6.1的分类，该表源于国家档案登记处2000年3月版的道路施工规范。目前大部分道路施工中的地基勘察包含以下提供有关岩土参数的试验方法：
◆ 取样孔
◆ 静压法取样 土方工程的地基勘察英文文献和中文翻译(6):http://www.youerw.com/fanyi/lunwen_13021.html