Sun Yongshuai, Wang Guihe, Li Yixuan
College of Water Resources & Civil Engineering, China Agricultural University, Beijing 100083, China.
School of Engineering and Technology, China University of Geosciences, Beijing 100083, China.
Materials (Basel). 2022 Jun 22;15(13):4412. doi: 10.3390/ma15134412.
To study the variation law of ultrasonic parameters of self-compacting concrete before and after damage under uniaxial compression test conditions, the C30 self-compacting concrete blocks stored for 7 days and 28 days were subjected to ultrasonic nondestructive testing, and the variation law of the sound time, amplitude, and sound velocity before and after the damage of self-compacting concrete blocks was emphatically analyzed. The concrete acoustic detection software was introduced to judge and analyze the abnormal values of the parameters of each measuring point, and the defect distribution map of each test block was obtained. The results showed that after curing the self-compacting concrete test block for 7 days and 28 days, the average value of sound time before and after the failure of each measuring point of the test block is small, and the average value of sound time before the failure is less than that after; the average amplitude after failure is smaller than that before failure, and the amplitude of some measuring points will be smaller than that before. The average sound velocity after failure is less than that before failure, and the internal defects appear and the structure is not dense. This study provides a theoretical basis for the application of ultrasonic detection technology in the field of self-compacting concrete and also provides a practical basis for the stability monitoring and failure warning of self-compacting concrete.
为研究单轴压缩试验条件下自密实混凝土损伤前后超声参数的变化规律，对养护7天和28天的C30自密实混凝土试块进行超声无损检测，着重分析自密实混凝土试块损伤前后声时、幅值及声速的变化规律。引入混凝土声学检测软件对各测点参数异常值进行判断分析，得到各试块的缺陷分布图。结果表明，自密实混凝土试块养护7天和28天后，试块各测点破坏前后声时平均值较小，破坏前声时平均值小于破坏后；破坏后平均幅值小于破坏前，部分测点幅值会小于破坏前。破坏后平均声速小于破坏前，内部出现缺陷，结构不密实。本研究为超声检测技术在自密实混凝土领域的应用提供了理论依据，也为自密实混凝土的稳定性监测和破坏预警提供了实践依据。
