One of the most damaging actions affecting concrete is the abrupt temperature change (freeze-thaw cycles). The types of deterioration of concrete structures by cyclic freeze-thaw can be largely classified into surface scaling (characterized by the weight loss) and internal crack growth (characterized by the loss of dynamic modulus of elasticity). The present study explored the durability of concrete made with air-entraining agent subjected to 0, 100, 200, 300, and 400 cycles of freeze-thaw. The experimental study of C20, C25, C30, C40, and C50 air-entrained concrete specimens was completed according to “the test method of long-term and durability on ordinary concrete” GB/T 50082-2009. The dynamic modulus of elasticity and weight loss of specimens were measured after different cycles of freeze-thaw. The influence of freeze-thaw cycles on the relative dynamic modulus of elasticity and weight loss was analyzed. The findings showed that the dynamic modulus of elasticity and weight decreased as the freeze-thaw cycles were repeated. They revealed that the C30, C40, and C50 air-entrained concrete was still durable after 300 cycles of freeze-thaw according to the experimental results.
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机译：影响混凝土的最具破坏性的作用之一是突然的温度变化（冻融循环）。循环冻融对混凝土结构的破坏类型可大致分为表面结垢（以重量损失为特征）和内部裂纹增长（以动态弹性模量为特征）。本研究探讨了用引气剂制成的混凝土在0、100、200、300和400次冻融循环下的耐久性。根据“普通混凝土的长期耐久性试验方法” GB / T 50082-2009，完成了C20，C25，C30，C40和C50空气加气混凝土试件的试验研究。在不同的冻融循环后，测量样品的动态弹性模量和重量损失。分析了冻融循环对相对动态弹性模量和重量损失的影响。研究结果表明，随着反复进行冻融循环，动态弹性模量和重量降低。他们发现，根据实验结果，经过300次冻融循环后，C30，C40和C50空气夹带的混凝土仍然耐用。
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