Calculation of optimized methods of the river underwater pipeline backfill with the use of APMWinMachine 9.7

Nowadays, the standard techniques of backing the ballasted pipeline laid in a bottom trench are used: sequential deposition of soil by suction dredges along the slurry pipeline, soil discharge by self-dumping barges, soil unloading from a barge by the grapple, soil pumping from barges. The disadvantage of these methods is that backfill is done in consecutive stages, and soil, falling into water increases water specific weight to the pulp specific weight. As a result, the buoyancy force increases and, when backfill is accomplished, the pipeline is raised above the design reference mark. The aim of the research is to optimize the existing methods of pipelines backfill, which will prevent or reduce the rise of the pipeline from the design position during its backfill. The optimized methods of the submerged pipelines backfill, which use temporal metal and reinforced concrete loads or backfill by cofferdams, have been calculated with the help of APMWinMachine software. The results of the model calculation by the method of finite elements show the effectiveness of the proposed methods of the submerged pipeline backfill.