ABSTRACT
The fork network of mains on the territory of Russia that are crossing the numerous water barriers produced a great number of underwater crossings. One of the main reasons of the underwater pipelines failure is river bed reforming. When repairing the exposed underwater pipeline sections , the flexible bracings based on geosynthetics use appear to be mostly fitted to bottom deformations. The investigations of filtration ability, strength, geosynthetics durability, deformability of protective coat models, rules of pipe models baring, influence of bracing models parameters upon baring protection efficiency were carried out. The results obtained are assumed as a basis for constructive decisions on repair of the 300 — 700 mm dia. gas lines crossing the rivers.
