Abstract
Currently, the bridges which were built in period of high economic growth are accounting for about 40% of all bridges and the deterioration of the high-strength bolts has become the important problem. It is necessary to diagnose periodically in order to find the deterioration of the high-strength bolts due to corrosion and metal fatigue and so on. The impact acoustics method is one of the diagnosis methods of the axial force. But, it is required the method that can diagnose more accurately and efficiently because the impact acoustics method has problems which depends on the engineer's experience and intuition, be required the high costs for the diagnosis and is shortage of the enough skilled engineer. In this study, we collected many wave pattern data of the impact acoustics that were taken by hitting the examination body which concluded the high-strength bolts with the tapping hammer and recognized the axial force by using the frequency data that were taken by converting the wave pattern data through the pattern recognition method.
