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摘要: 桥梁、隧道及工业民用建筑的安全监测和质量评价要求对混凝土结构件的内部状况进行无损检测, 常规的超声检测仪只给出一维接收声波, 直观性差, 判读困难, 为此开发了一种新的混凝土结构层析成像检测系统。系统中的超声源采用新开发的稀土换能器, 可输出大功率的窄脉冲信号, 穿过混凝土结构的超声信号由高速并行数据采集电路采集, 混凝土结构的内部层析成像计算采用改进的ART快速算法。在混凝土模拟试件的检测中, 系统给出的层析成像结果很好地显示出了试件的内部结构, 在某高速公路大桥桥墩的强度检测中, 测得的低密度区与回弹仪的测量结果一致, 说明开发的系统可以直观再现混凝土结构强度分布和内部缺陷。Abstract: The safety supervision and quality evaluation of bridges, tunnels and buildings require the nondestructive testing of their inner properties.Conventional ultrasonic testing equipment only processes one-dimension signals that it receives, from which it is hard to get a clear description of the concrete structures.So a new ultrasonic-tomography system was developed, a specially designed great power and short pulse ultrasonic emitter was used.The ultrasonic signals passing through the concrete structures were captured by high speed signal acquisition circuit.The inner features of the concrete structures were computed by improved fast ART algorithm.In the detection test of the inner defects of concrete sample, the tomography image produced by the system clearly shows the inner structure of test sample.In another bridge pier intensity test, the new system produces bridge intensity tomography images, which are coincident with the detection results by rebound measurer.The experiment results show that the developed system can reproduce the inner intensity distribution and defects of concrete structure, and can be effectively used for the safety supervision and quality evaluation of concrete construction.
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[1] 谢峻, 韩大建. 钢筋混凝土简支T型梁桥损伤识别的数值模拟[J]. 中国公路学报, 2004, 17 (4): 45-49. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL200404010.htmXie Jun, Han Da-jian. Numerical simulation of damage detection for simple-supported reinforced concrete T-beam bridge[J]. China Journal of Highway and Transport, 2004, 17 (4): 45-49. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL200404010.htm [2] 郭元术. 基于Wigner分布的混凝土灌注桩检测[J]. 长安大学学报: 自然科学版, 2001, 21 (4): 62-64. https://www.cnki.com.cn/Article/CJFDTOTAL-XAGL200104016.htmGuo Yuan-shu. Detection of foundation concrete piles based on Wigner distribution[J]. Journal of Chang'an University: Natural Science Edition, 2001, 21 (4): 62-64. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-XAGL200104016.htm [3] 索清辉, 钱永久. 服役公路桥梁的时变可靠指标计算[J]. 交通运输工程学报, 2006, 6 (1): 69-71. http://transport.chd.edu.cn/article/id/200601014Suo Qing-hui, Qian Yong-jiu. Time-dependent reliability index calculation of existed highway bridge[J]. Journal of Traffic and Transportation Engineering, 2006, 6 (1): 69-71. (in Chinese) http://transport.chd.edu.cn/article/id/200601014 [4] Bilgutay N, Popovics J, Popovics S, et al. Recent developments in concrete nondestructive evaluation[A]//IEEE International Conference on Acoustics, Speech and Signal Processing-Proceedings[C]. Salt Lake: IEEE Press, 2001. [5] 吴新璇. 混凝土无损检测技术手册[M]. 北京: 人民交通出版社, 2003. [6] 宁建国, 黄新, 曲华, 等. 冲击回波法检测混凝土结构[J]. 中国矿业大学学报, 2004, 33 (6): 703-707. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD200406020.htmNing Jian-guo, Huang Xin, Qu Hua, et al. Nondestructive testing of concrete structures usingimpact-echo method[J]. Journal of China University of Mining and Technology, 2004, 33 (6): 703-707. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD200406020.htm [7] Bond LJ, Kepler WF, Frangopol D M. Improved assessment of mass concrete dams using acoustic travel time tomography[J]. Construction and Building Materials, 2000, 14 (3): 133-156. doi: 10.1016/S0950-0618(00)00014-3 [8] Cui J R, Fang Y, Luo X B. Study on the principle of ultrasonic nondestructive testing of concrete[A]//Proceedings of the International Symposiumon Test and Measurement[C]. Shenz-hen: International Academic Publishers, 2003. [9] 杨文采, 李幼铭. 应用地震层析成像[M]. 北京: 地质出版社, 1993.