抄録
RTK-GPS (Real Time Kinematic-Global Positioning System) was applied to topographic survey in open-cut mines. The operation of the survey involves great difficulties, such as obstacles caused by local topography and electromagnetic noises interfering with micro-wave from GPS-satellites. Therefore, the survey was carried out under conditions when a good GPS-satellite constellation was formed in the sky, limited by local topography in each working face. A clear data link between two GPS-receivers on the working face was also important. In a field experiment at an operating open-cut mine, about 190 points were surveyed in about 5 hours on two successive days. Repeatability was estimated to be about ± 6 cm in coordinates obtained by the RTK-GPS. Topographic changes by operation were well pointed out by examining plotted RTK-GPS surveyed points on the topographic map surveyed by the traditional method. Consistency in coordinates was estimated to be about ± 9 cm between traditional local coordinates and those obtained by the RTK-GPS. Usefulness of the RTK-GPS was clearly demonstrated by examining actual field data acquired in operating open-cut mines. Rapid and precise measurement by the RTK-GPS is more suitable than the traditional optical surveying method for monitoring the topographic change in working face and for providing digital topographic data required for computer systems.