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一、引气剂定义在搅拌混凝土过程中能引入大量均匀分布、稳定而封闭的微小气泡的外加剂称为引气剂。这些气泡直径在50～250μm(0.05～0.25mm),引入混凝土中能增加新拌混凝土的流动性,可使混凝土拌合时适当的减少用水量。在硬化混凝土中,微小气泡能缓冲因水的冻结而产生的膨胀压力,减少冰冻的破坏。同时,微小气泡切断了硬化混凝土中的毛细管,减少由于毛细作用引起的渗透,提高了混凝土的抗渗性。因此,引气剂掺入混凝土中能减少混凝土拌合物的泌水离析,改善和易性,并能
First, the air entraining agent is defined in the process of mixing concrete can introduce a large number of evenly distributed, stable and closed micro-bubble admixture called air entrainment agent. These bubbles have a diameter of 50 to 250 μm (0.05 to 0.25 mm). The introduction of concrete can increase the fluidity of fresh concrete and can appropriately reduce the amount of water used for concrete mixing. In hardened concrete, tiny bubbles can buffer the expansion pressure caused by the freezing of water and reduce the damage of freezing. At the same time, the microbubbles cut the capillaries in the hardened concrete, reducing the penetration due to capillary action and increasing the impermeability of the concrete. Therefore, the introduction of air-entraining agent into the concrete can reduce the bleeding and segregation of the concrete mixture, improve the workability, and improve the workability.