含气量对机制砂混凝土耐久性能的影响

Effect of Air Content on Durability of Manufactured Sand Concrete

混凝土耐久性作为影响混凝土工程使用寿命的关键,已成为混凝土行业研究的重点。其中,混凝土含气量是影响混凝土耐久性的关键指标。为了进一步探究含气量对混凝土耐久性的影响,本文选取抗压强度、抗冻性能参数、相对动弹性模量和电通量等混凝土耐久性指标进行检测分析。试验结果表明:当混凝土中含气量逐渐增大时,混凝土7天和28天抗压强度逐渐降低,而混凝土的抗冻性能呈现先增加后减小的趋势;随着混凝土含气量的增加,混凝土的抗氯离子渗透能力不断增强,因此,在一定程度范围内,含气量的增加有利于混凝土耐久性的提高。

As the key to affect the service life of concrete engineering, concrete durability has become the focus of concrete industry research.Among them, the air content of concrete is the key index affecting the durability of concrete. In order to further explore the influence of air content on concrete durability, this paper selected concrete durability indexes such as compressive strength, frost resistance parameters, relative dynamic elastic modulus and electric flux for detection and analysis. The results showed that when the air content in concrete increased gradually, the compressive strength of concrete at 7 and 28 days decreased, while the frost resistance of concrete increased first and then decreased. With the improvement of air content in concrete, the anti-chloride ion permeability of concrete was continuously enhanced. Therefore, to a certain extent, the increase of air content is conducivetotheimprovementofconcretedurability.