关键词: 土石坝, 无损探测, 面波法, 自然电位法, 渗流分析

Abstract: Damage caused by abnormal seepage is one of the major hidden defects threatening the long- term safe operation of earth-rockfill dams. However, most traditional detection methods are destructive, which can cause damage to the dam structure and also have insufficient spatial detection resolution. Based on comprehensive geophysical exploration technology, collaborative detection by surface wave method and self-potential method was carried out at a core wall rockfill dam in Africa. The detection re_ sults showed that the combined application of the surface wave method and the self-potential method was feasible in the seepage analysis of earth-rockfill dams. The surface wave method can detect the area with abnormal density in the core wall dam based on the difference in shear wave velocity, while the self-potential method can detect the abnormal seepage area of the core wall dam by measuring the filter electric field formed by seepage. The combination of the two methods can give full play to their respec_ tive advantages, and the detection results can be verified by each other. Hence the detection of abnormal seepage areas is more accurate and effective, and it has good consistency in the seepage analysis of core wall dams.

Key words: earth-rockfill dam, non-destructive detection, surface wave method, self-potential method, seepage analysis