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首页> 外文期刊>Materials Characterization >Thaumasite Sulfate Attack, Popcorn Calcite Deposition and acid attack in concrete stored at the 《Blindtarmen》 test site Oslo, from 1952 to 1982
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Thaumasite Sulfate Attack, Popcorn Calcite Deposition and acid attack in concrete stored at the 《Blindtarmen》 test site Oslo, from 1952 to 1982

机译：1952年至1982年在奥斯陆“盲人试验”试验场中储存的混凝土中的脱硫铝石硫酸盐侵蚀，爆米花方解石沉积和酸侵蚀

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In past decades, concrete in contact with Oslo Alum Shale suffered severe deterioration, frequently involving quick and complete degradation of the cement paste matrix. The Norwegian Alum Shale Committee (1947-1972) concluded that this was due to secondary ettringite deposition and acid attack. The most resistant concrete mixes were based on Sulfate Resisting Portland Cements or those containing a pozzolanic supplementary cementitious mineral. However, the present work concludes that this "classic" sulfate attack was triggered by deleterious Thaumasite Sulfate Attack and Popcorn Calcite Deposition in close association with effects of externally derived acid attack. This paper provides an outline of the previous work and the first petrographic documentation of concrete prisms previously exposed at the "Blindtarmen" test site. Two important novel reaction mechanisms were also found: 1) the development of high crystallisation pressure associated with Thaumasite Formation, and 2) full scale Thaumasite Sulfate Attack was most efficient after partial or complete decalcification of calcium silicate hydrate: thaumasite had formed at the expense of remaining amorphous silica and associated secondary popcorn calcite. Comparison with modem sprayed concrete on Alum Shale shows that influence of Thaumasite Sulfate Attack and internal carbonation was faster under a hydraulic gradient than under static conditions.
机译：在过去的几十年中，与奥斯陆明矾页岩接触的混凝土遭受了严重的破坏，经常涉及水泥浆基质的快速，完全降解。挪威明矾页岩委员会（1947-1972）得出结论，这是由于二次钙矾石沉积和酸蚀所致。抵抗力最强的混凝土混合物是基于抗硫酸盐的波特兰水泥或含有火山灰补充胶结矿物的那些。但是，目前的工作得出的结论是，这种“经典的”硫酸盐侵蚀是由有害的硫马石硫酸盐侵蚀和爆米花方解石沉积引起的，与外部酸侵蚀的影响密切相关。本文概述了以前的工作，以及有关先前在“盲人门”试验场暴露过的混凝土棱镜的第一份岩石学文献资料。还发现了两个重要的新反应机理：1）与Thaumasite形成相关的高结晶压力的发展; 2）完全或部分脱钙硅酸钙水合物的脱钙后，全尺寸Thaumasite硫酸盐的侵蚀最有效：形成Thaumasite的代价是剩余的无定形二氧化硅和相关的二次爆米花方解石。与明矾页岩上的现代喷射混凝土的比较表明，在水力梯度条件下，相比于静态条件，硫柳石硫酸盐侵蚀和内部碳化的影响更快。

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