Over 12 000 houses built in Ireland between 2002 and 2008 are estimated to have sustained structural damage due to swelling initiated by pyrite in crushed rock aggregate beneath floor slabs. The Irish Standard I.S. 398-1 presented a categorization protocol for sub-floor fill material suspected of causing pyritic expansion. While at the extremes, the current risk characterisation protocol is definitive, there is a broad range of conditions where the findings are inconclusive, and the risk assessment requires expert interpretation. In this study, the possibility of using trace-element analysis to better quantify risk from reactive pyrite has been explored. The form and amount of pyrite in sedimentary rock are determined by the depositional environment, which also determined the concentration of trace elements such as molybdenum (Mo) and uranium (U). In this study, a range of high- and low-risk aggregates has been analysed. The results show very good correlation between the empirically derived risk for pyrite expansion categories and molybdenum and uranium enrichments and the ratio between these concentrations. The results to date are very promising and suggest that further research and testing of more samples will help to confirm the basis of the analysis and establish numerical risk thresholds.

中文翻译：

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黄铁矿隆起问题：来自微量元素分析的新见解

据估计，2002 年至 2008 年间在爱尔兰建造的 12 000 多座房屋由于楼板下方碎石骨料中的黄铁矿膨胀而遭受结构性损坏。爱尔兰标准 IS 398-1 提出了疑似导致黄铁矿膨胀的底层地板填充材料的分类协议。虽然在极端情况下，当前的风险表征协议是明确的，但在广泛的情况下，结果尚无定论，风险评估需要专家解释。在这项研究中，探讨了使用微量元素分析更好地量化活性黄铁矿风险的可能性。沉积岩中黄铁矿的形态和数量由沉积环境决定，也决定了钼（Mo）、铀（U）等微量元素的浓度。在这项研究中，分析了一系列高风险和低风险的聚合体。结果表明，根据经验得出的黄铁矿膨胀类别与钼和铀富集的风险以及这些浓度之间的比率之间具有非常好的相关性。迄今为止的结果非常有希望，并表明对更多样本的进一步研究和测试将有助于确认分析的基础并建立数值风险阈值。