掺Ⅱ级粉煤灰混凝土的抗硫酸盐侵蚀性能研究

Research on Sulfate Resistance of Ⅱ Class Fly Ash Concrete

对掺Ⅱ级粉煤灰的混凝土，改变其水胶比和粉煤灰掺量，进行抗硫酸盐侵蚀试验，结果表明：水灰比为0．40的普通混凝土，无法抵抗硫酸根离子浓度2500-20250mg／L硫酸盐溶液侵蚀，其水泥石孔隙中侵蚀产物以石膏为主，侵蚀现象主要发生在试件的表层，具体形态表现为试件表层逐渐疏松、剥落。水胶比为0．40以下、粉煤灰掺量30％及其以上的混凝土能够抵抗硫酸根离子浓度为20250mg／L的硫酸盐侵蚀。

Sulate resistarce experiments about Ⅱ class fly ash concrete wiht different ratio of water/cement and fly ash are carried out it shows that： Ordinary concrete water cement ratio of 0.40can＇t resist S042- 2500 ～ 20250 mg/L sulfate solution erosion, because Corrosion products is mainly gypsum in cement stone pore.Erosion occurs mainly in the surface of the specimens, the shape of specimen surface gradually loose, spalling. Water/cement ratio below 0.40, more than 30% dosage of fly ash concrete can resist S042- 20250mg/L sulfate attack.