超声波相控阵测试混凝土波速试验研究

Experimental Research on Ultrasonic Phased Array Testing of Concrete Wave Speed

采用超声波相控阵设备检测超声波在混凝土内的传播波速,考察波速与混凝土配置强度、龄期的相关性。首先成型了配置强度为C30C40C50的多组混凝土试件,分别在龄期为4天、15天、30天时进行超声波相控阵线扫描测试。通过读取测试时各道超声波信号峰值延迟时间,推断超声波在混凝土中的传播波速度。测试结果表明:超声波波速在同一试件的测试结果具有良好的重复性,揭示干接触超声波探头具有良好的工作性能;超声波频率在20-60 kHz以内变化时,混凝土超声波波速变化小于1%;不同龄期、不同配置强度的混凝土波速有明显差异,显示超声波相控阵波速能够区分混凝土强度特征。现场对某预制构件表面进行混凝土波速度测试,发现的低波速区域经验证存在混凝土质量缺陷。

Ultrasonic phased array equipment is used to detect the propagation wave speed of ultrasonic waves in concrete,and the correlation between wave speed and concrete configuration strength and age is investigated.First,multiple groups of concrete specimens with configuration strengths of C30C40C50 were formed,and ultrasonic phased array line scanning tests were conducted at 4 days,15 days,and 30 days respectively.By reading the peak delay time of each ultrasonic signal during the test,the propagation wave speed of ultrasonic waves in concrete can be inferred.The test results show that:the test results of ultrasonic wave speed on the same specimen have good repeatability,revealing that the dry contact ultrasonic probe has good working performance;when the ultrasonic frequency changes within 20-60 kHz,the change in concrete ultrasonic wave speed is less than 1%;no There are significant differences in the wave speed of concrete at the same age and with different configuration strengths,showing that the ultrasonic phased array wave speed can distinguish the strength characteristics of concrete.A concrete wave velocity test was conducted on the surface of a certain prefabricated component on site,and the low wave velocity areas found were verified to contain concrete quality defects.