Application and Analysis of 3D Seismic Reflection Technology in the Subsea Tunnel Survey

Research purposes: Due to problems such as the maritime traffic environment, the marine beacon condition and the changing terrain and geological conditions, the traditional survey methods and equipments have many limitations in subsea tunnel engineering survey. Based on the project and combined with the characteristics of the project site, the 3D seismic reflection technology was applied to investigate the subsea tunnel engineering, and the new idea of subsea tunnel in complex environment was explored, to provide reliable survey results for engineering design. Research conclusions:(1) Based on the 3D seismic reflection technology and correction of drilling results, we can accurately simulate the shape, position and mutual contact relationship of each ground level and structure, and provide reliable geological basis and physical parameters. (2) According to the 3D geological modeling results, we can analyze the geological conditions of the tunnel section and provide the geotechnical geological conditions of the tunnel, which can provide reliable basis for engineering design. (3) Geological modeling combined with multi-source data can significantly improve the accuracy of geological model. Analysis shows that the average difference percentage can reach 0.907%, which gets high accuracy and good reliability. (4) The research results can be applied in the investigation of the underwater tunnel. © 2022, Editorial Department of Journal of Railway Engineering Society. All right reserved.