卡尼亚·安德烈兹,斯塔维斯基·马雷克

混凝土的硫酸盐腐蚀是一个复杂的化学和物理过程，会导致建筑构件的损坏。混凝土的降解是由于硫酸盐化合物通过暴露元件的孔隙传输及其与胶结材料的化学反应造成的。暴露在腐蚀环境中的各种结构都会发生硫酸盐腐蚀。硫酸根离子与混凝土化合物发生化学反应的机理是众所周知的，并且已有文献描述。此外，文献还描述了标准立方体样品的抗压强度与其在硫酸盐腐蚀环境中暴露时间的关系。然而，科学文献中对标准样品进行的强度测试并未提供有关暴露于硫酸根离子的钢筋混凝土结构横截面抗压强度测量方法和实际分布的问题的答案。由于很难在文献中找到对此类测试的任何描述，作者着手进行这些测试。作者选择使用与材料接触的点表面的指数头的超声波方法来测量平行于腐蚀表面的近截面的混凝土强度。该测试是对从钢筋混凝土罐的隔间中取出的样品进行的，该罐在腐蚀环境中运行了五年。测试结果表明，在测试元件的整个厚度上强度不均匀。经确定，结构内部横截面中的构件强度比初始强度高出 80%。作者仅在暴露表面附近的封闭区域观察到混凝土的机械性能下降。

具体要素；混凝土强度；钢筋混凝土储罐；混凝土腐蚀；硫酸盐腐蚀

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