In this paper, we discuss the results of application of “Integrated system of digital hammering inspection and digital visual inspection” to the detectability of flacking, cracks and backside cavities of the tunnel lining as well as flacking and backside cavities of concrete paving in a national highway tunnel....
英字タイトル:
Development of diagnostic technology for concrete structures using digital hammering inspection

Non-destructive testing technique was developed for embedded plates using phased-array ultrasonic testing (PAUT). The bending angle of their studs was quantitatively estimated by using the sector scan of PAUT, which is usually difficult by using conventional UT. In addition, this technique is capable of visualizing the weld shape of the stud by using the linear scan of PAUT. Mockup tests were carried out in order to verify the effectiveness of the technique....
英字タイトル:
Development of Testing Technique on Embedded Plates Using Phased-Array Ultrasonic Testing

We have developed a simplified diagnosis method of hammering inspection using AE (Acoustic Emission) sensor applicable to chemical anchors in nuclear power plants. The database was created to identify improper installation and aging of the anchors. We have also confirmed its applicability to other types of anchor (e.g. anchor bolts, mechanical anchors). The details of development process are described in this paper....
英字タイトル:
Developing a simplified diagnosis method for anchor bolts (2)

Abstract As an attempt to apply AI in the field of maintenance, we have been studying "forward analysis", "inverse analysis" and "future prediction". As for the “forward analysis”, as a theoretical verification of the digital hammering inspection results using the AE sensor, the natural frequency obtained in the hammering inspection is confirmed by “time history response analysis”. Because there is a combination of the shape, material properties to be inspected, measuring position of natural frequency, etc....
英字タイトル:
Attempts of forward analysis, reverse analysis and future prediction using AI in the field of maintenance

Non-destructive evaluation technique was developed to identify the integrity of embedded hardware using digital hammering inspection with AE (Acoustic Emission) sensor. The inspection can diagnose the fixed state of the embedded hardware in terms of its natural frequency and vibration duration. Mockup tests were conducted to investigate the relationship between the change in vibration duration and the fixed state under various loads including external tensile loads and thermal loads when welding supports on...
英字タイトル:
Improvement of the efficiency of hammering inspection using AE sensor for embedded hardware 2

Non-destructive evaluation technique was developed for embedded hardware using hammering inspection with AE (Acoustic Emission) sensor. The integrity of the studs welded on the hardware is judged from both the vibration duration of the embedded hardware and the frequency analysis of the vibration signal. The hammering inspection has been applied to the reprocessing plant of JNFL (Japan Nuclear Fuel Limited) for three years and we are now planning the improvement of the efficiency of the inspection in variou...
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Improvement of the efficiency of hammering inspection using AE sensor for embedded hardware

As an attempt to apply AI in the field of maintenance, we have been developing a diagnosis method of check valves to detect the internal leakage and the signal before the leakage based on the signal analysis of their vibration measurements by a portable system with AE (Acoustic Emission) sensors. CNN (Convolutional Neural Network) was applied to the measured raw waveform and its frequency distribution corresponding to the leakage rates in order to classify the leakage rates. The leakage rate was gradually i...
英字タイトル:
Study on the Application of AI to Check Valve Diagnosis

The purpose of this research is development of tension measurement method using hammering sound diagnosis technology using Acoustic Emission sensor. Experiments using actual size anchors and FEM analysis quantitatively evaluated the relationship between the vibration characteristics of the anchor head and the tension introduced into the anchor. As a result, it is possible to evaluate the anchor tension based on the natural vibration characteristics of the anchor head. ...
英字タイトル:
Evaluation of tension of ground anchor by hammering test using AE sensor Vol.1

The purpose of this research is development of tension measurement method using diagnostic technique of hammer sound using acoustic radiation sensor. This report summarizes the method of evaluating the anchor tension based on the natural frequency of the anchor head and the applicability of the method to measured data at the site....
英字タイトル:
Evaluation of tension of ground anchor by hammering test using AE sensor Vol.2