Method for calculating and analyzing back silting after excavation of large-diameter pipeline in open sea area

The invention relates to the technical field of submarine pipeline laying, and discloses an open sea area large-diameter pipeline excavation back-silting calculation and analysis method which comprises the following steps: S1, collecting related basic data before and after excavation of a pipeline foundation trench; s2, establishing a submarine topographic map before and after excavation of the pipeline foundation trench; s3, establishing a wave power flow prediction model of the sea area where the pipeline foundation trench is located, and predicting wave power flow characteristics of the sea area where the pipeline foundation trench is located; s4, establishing a three-dimensional mathematical model of pipeline foundation trench back silting, and carrying out numerical simulation calculation; and S5, calculating the area of the back-silting region and the back-silting thickness of different regions based on post-processing software, and counting and calculating the back-silting amount of the pipeline founda