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从1948年挪威将硅灰作为混凝土的添加剂以来已过去约半个世纪。八十年代在美国的高层建筑的建设高潮中,为了达到700～1000kg/cm~2的抗压强度,硅灰被宣传成为高强混凝土混合材。进入九十年代后,硅灰作为改善混凝土耐久性的材料再次受到瞩目。在桥板、海洋构筑物和停车楼等设计中,借助硅灰提高强度和抗氯离子渗透性能。硅灰比表面积高达20000m~2/kg,在混凝土中,进入水泥颗粒之间形成微细孔结构。在水泥水化初期,硅灰成为核心,促进水化,具有保水性,大幅度降低离析程度。在水化后期,与氢氧化钙
It has been about half a century since Norway introduced silica fume as an additive for concrete in 1948. In the 1980s, during the construction boom of high-rise buildings in the United States, in order to achieve a compressive strength of 700-1000 kg/cm 2 , silica fume was advertised as a high-strength concrete mixture. After entering the 1990s, silica fume has once again received attention as a material that improves the durability of concrete. In bridge decks, marine structures, and parking buildings, the use of silica fume enhances strength and resistance to chloride penetration. The specific surface area of silica fume is up to 20000m~2/kg. In concrete, fine pore structure is formed between cement particles. In the initial stage of cement hydration, silica fume becomes the core, promotes hydration, has water retention, and greatly reduces segregation. In the later period of hydration, with calcium hydroxide