钡盐对混凝土抗硫酸盐侵蚀的有效性研究

Effective investigations of barium salts on suppressing the sulfate attack damage for concrete

通过一年的浸泡试验,系统研究了钡盐对混凝土抗硫酸盐侵蚀作用的有效性。结果表明,钡盐对混凝土硫酸盐侵蚀破坏的改善作用与其种类和掺量有关。其中,掺量小于1.0%的氢氧化钡能改善混凝土的抗硫酸盐侵蚀性能。氢氧化钡改善混凝土抗硫酸盐侵蚀性能的机理是通过生成适量的BaSO4来降低SO42-离子浓度并细化毛细孔的孔径,达到降低石膏和钙矾石晶体的生成速度,进而起到延缓混凝土硫酸盐侵蚀破坏的速度。

To investigate the effects of barium salts on the sulfate attack, a series of concrete prisms immersion tests were carried out respectively in the 10% Na2SO4 solution for one year.The results showed that the effects of barium salts on suppressing the sulfate attack damage for concrete are related to their types and contents.Barium hydroxide whose content is less than 1.0% replacement of cement by mass can suppress the sulfate attack damage for concrete. When barium hydroxide is added in the concrete, Ba^2＋ and SO4^2- can produce barium sulfate which prevents AFt and gypsum crystal from forming.