Flaw Detection of the Aged Bridge on National Roadway by Impact Echo Testing

충격반향기법을 이용한 국도상 노후교량의 결함검사

As nation's infrastructure is getting old, nondestructive evaluation of existing structures and construction quality control are getting important. In this thesis, flaw detection techniques of concrete members with asphalt using impact echo test were introduced. This techniques are based on stress wave propagation. In this field impact echo test, As load is gradually increased, frequency is increased. From this change of frequency through impact echo test, we can detect that the crack of bridge ascends and what the depth of crack is.