Abstract:Underwater structure detection is the basis and important link of operation and maintenance management and safety assessment of water related projects. The underwater structure detection technology based on sonar system can directly reflect the service status of underwater structures through point cloud imaging, and provide technical support for operation manage- ment, emergency repair and safety evaluation of water related projects. Combined with an engineering example, this paper tests and verifies the detection effect of the underwater sonar imaging system. The results show that the underwater sonar imaging de- tection system has good detection effect and can also better complete the underwater detection task in the low visibility environ- ment with turbid water quality. Compared with the traditional detection methods, the system has the advantages of strong adapt-ability to underwater environment, flexible operation, intuitive and efficient, and greatly improves the accuracy and efficiency of underwater structure detection.