混凝土冻融损伤厚度的超声波检测

Ultrasonic detection of freeze-thaw damage thickness of concrete

为分析混凝土结构的冻融损伤厚度,采用快冻法进行引气混凝土试验梁在质量分数为3.5%的NaCl溶液中的盐冻试验.基于超声脉冲检测方法,依据波速在不同物质中的传播速度差异,对冻融300次后的混凝土试块进行超声检测,得到混凝土冻融损伤厚度.结果表明,该配合比对应的混凝土试块在冻融循环300次后冻融厚度约为30 mm,未超过混凝土结构的钢筋保护层厚度.

In order to analyze freeze-thaw damage thickness of concrete structure, the salt frost test of the concrete beam which was immerged in 3.5 % NaC1 salt solution was made by a quick freezing method. Based on ultrasonic detection methods, non-metallic ultrasonic instrument was used according to the propagation speed difference of wave velocity in different materials. The thaw cycles. The results show that, the damage thickness of the concrete specimen was detected after 300 freeze- damage thickness of concrete specimen after 300 times freeze-thaw cycles is 30 mm, which is less than the protective layer of reinforcements.