1998 Volume 7 Pages 1481-1483
Concrete structures which need repair and maintenance work because of salt damage have recently increased in number. Hence, in maintenance management, it is necessary to chip off the existing concrete surface and to cut away salt damaged areas efficiently. Until now, this has depended primarily on manual operation by using pick hammers and the like. However, work efficiency tended to be low due to the extremely poor working environment that offen involved heavy vibration and noise, and it has been shown that the impact of the chipping operations has adverse quality effects in undamaged sections. Therefore, the development of a new method was strongly demanded. An automated chipping system to cut away the salt damaged areas by utilizing high pressure water jets has been developed and applied to actual reinforcing work. This report details the development of an automatic water jet chipping method applied to large-scale reinforcing work on a salt damaged pre-stressed concrete bridge, and also describes the results of on-site implementation and improvement.
