Abstract: With the rapid development of technologies related to underwater acoustic measurement, computer, navigation, positioning and digital sensors, multibeam bathymetry technology has been widely used in engineering fields such as underwater terrain surveying and underwater building detection. The paper introduces the basic principles and system composition of multibeam bathymetry technology. Combined with the application of multibeam bathymetry technology to analysis of scour downstream of Jinping Ⅱ hydropower dam, the application of measurement results was discussed, which can provide a reference for similar scour analysis.

Key words: underwater measurement, GPS-RTK, multibeam bathymetry, scour calculation

摘要： 随着水声、计算机、导航定位和数字化传感器等技术快速发展，多波束测深技术已广泛应用于水下地形勘测和水下建筑物探测等工程领域。笔者介绍了多波束测深技术基本原理及系统组成，结合其在锦屏二级水电站坝后冲刷分析中的应用，探讨了测量成果的应用效果，为类似冲刷分析研究提供了参考。

关键词: 水下测量, GPS-RTK, 多波束测深, 淘空计算