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第 39 卷 第 3 期                                                                       Vol. 39, No. 3
             2020 年 5 月                          Journal of Applied Acoustics                      May, 2020

             ⋄ 研究报告 ⋄



                    时域有限差分法的混凝土超声波损伤分析                                                             ∗




                                           刘昌明     1   陈亚琦      2  王志刚      1,2†

                                    (1  武汉科技大学    冶金装备及其控制教育部重点实验室           武汉  430081)
                                   (2  武汉科技大学    机械传动与制造工程湖北省重点实验室           武汉   430081)

                摘要：混凝土质量的好坏直接影响到建筑物的安全性，选用方便实用的方法对其内部裂纹进行检测具有显著
                意义。该文首先借助时域有限差分法，建立了混凝土声场数学模型。之后对不同内部缺陷尺寸的混凝土模型
                进行了超声波数值模拟，分别从时域和频域对接收到的超声信号进行了分析。结果发现，当内部存在缺陷时，
                接收信号时域幅值明显变小，接收信号的幅值与缺陷尺寸大小呈指数关系，且接收信号传播时间与缺陷宽度
                呈线性关系。最后以初次到达信号的频域能量为特征指标，得出其与混凝土内部开裂缺陷尺寸呈指数关系。
                该方法为混凝土超声无损检测建立合适的数学模型提供了参考。
                关键词：超声检测；混凝土；缺陷；数值仿真；有限差分
                中图法分类号: TH113           文献标识码: A          文章编号: 1000-310X(2020)03-0360-06
                DOI: 10.11684/j.issn.1000-310X.2020.03.006

                       Ultrasonic damage analysis of concrete based on finite difference

                                                time domain method


                                    LIU Changming  1  CHEN Yaqi  2  WANG Zhigang   1,2

                 (1  Key Laboratory of Metallurgical Equipment & Control Technology of Ministry of Education, Wuhan University of
                                           Science and Technology, Wuhan 430081, China)
                   (2  Ministry of Education, Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering,
                                   Wuhan University of Science and Technology, Wuhan 430081, China)

                 Abstract: The quality of concrete directly affects the safety of buildings. It is significant to select convenient
                 and practical methods to detect the internal cracks of concrete. Firstly, the mathematical model of concrete
                 acoustic field was established by means of finite difference time domain method. Then, the ultrasonic numerical
                 simulation of concrete models with different internal defect sizes was carried out, and the received ultrasonic
                 signals were analyzed in time domain and frequency domain respectively. The results show that when there are
                 internal defects, the time-domain amplitude of the received signal decreases significantly, the amplitude of the
                 received signal is exponentially related to the size of the defect, and the propagation time of the received signal
                 is linearly related to the width of the defect. Finally, the frequency domain energy of the first arrival signal was
                 taken as the characteristic index, and the exponential relationship between the defect size and the crack size
                 in concrete was obtained. This method provides a reference for concrete to establish a suitable mathematical
                 model for ultrasonic nondestructive testing.
                 Keywords: Ultrasonic testing; Concrete; Defect; Numerical simulation; Finite difference


             2019-07-05 收稿; 2019-10-23 定稿
             国家自然科学基金项目 (51505346), 国家留学基金项目 (201808420131)
             ∗
             作者简介: 刘昌明 (1984– ), 男, 山东威海人, 博士, 副教授, 研究方向: 复合材料力学行为研究与故障诊断。
             † 通信作者 E-mail: wzhigang@wust.edu.cn
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