To improve the workability by fixing a base plate to a bracket, which is fixed to an arm, and fixing a shaking means to the base plate, and while fitting a concrete grain raising means or the like.

When a hydraulic motor of a shaking device 16 is driven, an eccentric wheel is rotated in the condition that it is deviated in the right and left direction so as to eccentrically rotate a base plate 15 in the right and left direction and the vertical direction through a housing 25. In response to the rotation of the eccentric wheel, when one of vibration-proof rubbers 17A, 17B is compressed, the other is stretched, and when one of vibration damping rubbers 17C, 17D is compressed, the other is stretched so as to reduce the vibration of the base plate 15 in the right and left direction and enlarge the vibration thereof in the vertical direction. Furthermore, when a grain raising bar 35, which is fitted to the tip of an arm 12 and an operating rod 13a, is pushed to a concrete wall surface, the grain raising bar 35 is vibrated in the vertical direction so as to cut into the concrete wall surface for the generation of damage.