Thousands of homes in County Donegal, Ireland, built from concrete blocks, are damaged by extensive cracks and crumbling that occurred a few years after construction. Recently, research has shown that pyrrhotite oxidation triggering internal sulfate attack (ISA) is the cause. In this study, samples from the strip foundations, the rising blocks, the outer and inner leaf of one undamaged reference home and three affected homes are investigated. As these four structural components differ by concrete quality, exposure condition or both, their effect on ISA is investigated. All three damaged homes contained pyrrhotite in the aggregates, while it was absent in the reference home. ISA in the foundations is in an initial state. It has progressed further in the rising blocks and is most advanced in the outer leaf. Whilst carbonation limits the effects of ISA in the inner leaf, further pyrrhotite oxidation will create expansion leading to ongoing deterioration.

中文翻译：

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爱尔兰多尼戈尔的缺陷房屋：暴露条件和混凝土质量对磁黄铁矿氧化和内部硫酸盐侵蚀的影响


爱尔兰多尼戈尔郡 （County Donegal） 有数千栋房屋由混凝土砌块建造而成，在施工几年后因大面积裂缝和崩塌而受损。最近，研究表明，磁黄铁矿氧化触发内部硫酸盐攻击 （ISA） 是原因。在这项研究中，调查了来自一个未受损参考房屋和三个受影响房屋的条形地基、上升块、外叶和内叶的样本。由于这四个结构组件在混凝土质量、暴露条件或两者方面有所不同，因此研究了它们对 ISA 的影响。所有三栋受损房屋的骨料中都含有磁黄铁矿，而参考房屋中则没有。基础中的 ISA 处于初始状态。它在上升的块中进一步发展，在外叶中最为先进。虽然碳酸化限制了 ISA 在内叶中的作用，但进一步的磁黄铁矿氧化将产生膨胀，导致持续变质。