진동신호법을 이용한 콘크리트의 균열추정에 관한 연구

Abstract

This paper describes a method to estimate the position of a crack in a concrete block using several vibration pick-up sensors. An array of vibration pick-up sensors in attached on the concrete block, and a vibration pulse is forced by using a impact hammer. If there is a crack or groove, a reflection wave is generated from the position of the crack. However, since the concrete block is springy, there are three wave propagation modes; the primary wave mode, the secondary wave mode and the surface wave mode. Since the necessary primary wave mode is not significant in magnitude, we cannot estimate the position of crack in concrete block. To increase the S/N , we had proposed a method to eliminate the first-coming surface wave. However, the method was insufficient to achieve a higher S/N. Therefore, this paper proposes a new method to achieve a better location of a crack. Some experiments were carried out, and good results were obtained.