硫酸钠溶液对混凝土抗冻性的影响

对混凝土在硫酸盐侵蚀条件下的抗冻性进行了实验研究，分析了硫酸钠溶液影响混凝土抗冻性的机理，结果表明，水灰比不同的混凝土，受到硫酸钠溶液影响的程序有所不同：水灰比较高，强度较低的混凝土，其弹性模量的下降比在水中时稍慢，抗冻融循环次数稍多；水灰比较低，强度较高的混凝土则由于硫酸盐侵蚀发挥作用，所以要比在水中冻融更早达到破坏，破坏形态为断裂。

Effect of Sodium Sulphate Solution on the Frost Resistance of Concrete

In this paper, the freezing and thawing properties of concrete in sodium sulphate solution were investigated. The experimental results showed that the influence of sodium sulphate solution is different for concrete with different m w/ m c. For concrete with higher m w/ m c, the decrease of relative dynamic modulus of elasticity exhibites a slight slower in sulphate solution than that in fresh water during the process of freezing and thawing cycles. In sulphate solution, the concrete can take more cycles of freezing and thawing than that in water. However, for high strength concrete with lower m w/ m c, the failure of concrete occurs earlier in solution than that in fresh water due to the sulphate attack. The failure mode is brittle crack.