不同条件下水工混凝土抗冻指标演化规律研究

Evolution Law of Frost Resistance Index of Hydraulic Concrete Under Different Conditions

水工混凝土抗冻性演化规律是确定寒区水工混凝土养护时机的先决条件,有助于延长寒区水工混凝土的使用寿命。基于此,文中对不同水灰比及不同石灰岩粉末掺量下,不同冻融循环次数与水工混凝土质量损失率、相对动态弹性模量等抗冻指标关系的演化规律进行研究。结果表明,水工混凝土的质量损失系数与冻融循环次数呈现正相关关系,且随着水灰比的增加及石灰岩粉末掺量的增加,其质量损伤衰变速率也有所增加。冻融循环次数越多,水工混凝土相对动弹性模量越低;水灰比越大,石灰岩掺量越高,其相对动弹性模量衰变速率更快。

The evolution law of frost resistance of hydraulic concrete is a prerequisite to determine the curing time of hydraulic concrete in cold area,which is helpful to prolong the service life of hydraulic concrete in cold area.Based on this,the paper studies the evolution of frost resistance indexes such as mass loss rate and relative dynamic modulus of hydraulic concrete under different water-cement ratio and different limestone content and different freeze-thaw cycles.The results show that the mass loss coefficient of hydraulic concrete is positively correlated with the number of freeze-thaw cycles,and the mass damage decay rate begins to increase with the increase of water-cement ratio and limestone powder content.The relative dynamic elastic modulus of hydraulic concrete is negatively correlated with the number of freeze-thaw cycles.The higher the water-cement ratio,the more limestone powder content,and the faster the decay rate of the relative dynamic elastic modulus.