Analyze and compare the basic principles of ultrasonic detection of voids in concrete,choose ZBL-U520/510 non-metallic ultrasonic detector,and use the opposite detection method to test the void size in the joints of p...Analyze and compare the basic principles of ultrasonic detection of voids in concrete,choose ZBL-U520/510 non-metallic ultrasonic detector,and use the opposite detection method to test the void size in the joints of prefabri-cated concrete structures.The results show that:ultrasonic method by testing the waveform,sound,and speed of sound analysis can effectively determine the position of the defect,and through the conversion formula can estimate the void size.Ultrasonic parameters are used to distinguish the internal defects of Assembly concrete.Sometimes there are diferent results with different para-meters.It is difficult for engineers to directly determine the internal de fects.Fuzzy comprehensive ev aluation can establish an overall evaluation of things or objects controlled by multiple factors by establishing membership functions.Through the inspection of engineering examples:the fuzzy comprehensive judgment method has no difference between the judgment of some good quality points and the judg-ment results of the original criteria,but for some abnormal points or points near the critical value,the advantages of fiuzzy criteria can be achieved.The judgment process will be more scientific by considering several parameters in a comprehen-sive manner and digtizing the original subjective judgments.展开更多
基金The authors are grateful for the financial support received from the National Key R&D Program(2017YFF0205003)Hebei Province Higher Education Science and Technology Research Project(ZD2018249)Special funded by the Beijing Institute of Housing and Urban-Rural Science and Technology.
文摘Analyze and compare the basic principles of ultrasonic detection of voids in concrete,choose ZBL-U520/510 non-metallic ultrasonic detector,and use the opposite detection method to test the void size in the joints of prefabri-cated concrete structures.The results show that:ultrasonic method by testing the waveform,sound,and speed of sound analysis can effectively determine the position of the defect,and through the conversion formula can estimate the void size.Ultrasonic parameters are used to distinguish the internal defects of Assembly concrete.Sometimes there are diferent results with different para-meters.It is difficult for engineers to directly determine the internal de fects.Fuzzy comprehensive ev aluation can establish an overall evaluation of things or objects controlled by multiple factors by establishing membership functions.Through the inspection of engineering examples:the fuzzy comprehensive judgment method has no difference between the judgment of some good quality points and the judg-ment results of the original criteria,but for some abnormal points or points near the critical value,the advantages of fiuzzy criteria can be achieved.The judgment process will be more scientific by considering several parameters in a comprehen-sive manner and digtizing the original subjective judgments.
