轻烧MgO膨胀剂对水工混凝土耐久性能的影响

Effects of Light-Burned MgO Expansive Agent on Durability of Hydraulic Concrete

文章研究了外掺轻烧MgO膨胀剂对C25水工混凝土的抗水渗透性能、抗氯离子渗透性能、抗冻性能和抗碳化性能的影响,探讨了轻烧MgO膨胀剂的掺量及水化活性值对C25水工混凝土耐久性能的影响。结果表明:轻烧MgO膨胀剂在外掺6%范围内,随着掺量增加,C25混凝土的抗渗性能、抗碳化能力提升;MgO水化活性值越低,混凝土的碳化深度越低;150次冻融循环内,外掺6%以内轻烧MgO膨胀剂对抗冻性无明显影响。外掺6%以内轻烧MgO膨胀剂对水工混凝土耐久性具有改善作用。

Impermeability, frost resistance and carbonation resistance of C25 hydraulic concrete with and without light-burned MgO expansive agent were measured, and the effects of admixture amount and hydration activity value of light-burned MgO expansive agent on durability of hydraulic concrete were investigated. The results showed that within 6% MgO expansive agent, the higher admixture amount, the better impermeability and carbonation resistance of C25 hydraulic concrete. The carbonation degree of C25 hydraulic concrete decreased with the decreasing of hydration activity value. Within 150 times freezing and thawing cycles, the addition of light-burned MgO expansive agent within 6% had no significant effect on frost resistance. The durability was enhanced by the addition of light-burned MgO expansive agent within 6%.