Keyword: «permafrost soils»

One of the main problems typical for Republic of Sakha (Yakutia) power system is a high percentage (more than 60%) power lines wear. More than 70% lines have been operating for more than 25 years, there is a massive decay of the supports and their destruction. Periodic freezing and thawing at the upper boundary of permafrost leads to support piles expulsion, as a result, to their fall and occurrence of a high accident rate in networks. The main goal of the work was to develop foundation solutions (FR) design from composite materials for single- and double-circuit, intermediate and anchor supports with wooden and concrete posts, excluding buckling of supports of 6, 10, 35 kV overhead lines.

This paper presents data on the largest accidents associated with oil and petroleum product spills in the Re-public of Sakha (Yakutia). A comparative assessment of the condition of soils taken from the territory of a technogenic object (oil depot) and a natural object (forest lands) contaminated with oil products is given. It is shown that peculiarities of distribution and degradation of oil hydrocarbons depend on many factors such as: the volume of spilled oil products, their composition, period of occurrence and duration of exposure, type of soil, presence of permafrost, climatic features, etc. A comprehensive study of the peculiarities of oil hydro-carbons behavior in permafrost soils makes it possible to carry out scientifically based monitoring of the state of territories with high anthropogenic loads.

The development of the oil and gas industry is solely related to the development of new northern territories of the Russian Federation. The development of deposits in permafrost conditions dramatically increases the cost of construction, primarily foundation work. One of the ways to reduce the cost of construction is to abandon the post-welding heat treatment of welded joints of straight seam welded microwave pipes. The paper presents the results of studies of mechanical properties, corrosion resistance, crack resistance, and fatigue tests confirming the possibility of eliminating excessive heat treatment.

This paper presents a numerical simulation of the behavior of a cast-in-place steel pile filled with cement-sand grout under the conditions of permafrost soils in the Arctic. Physically based soil models (MO Granular and Cam-Clay) were employed within the ANSYS Workbench software suite. Both vertical and combined loading scenarios typical for pipeline supports were considered. Computational results were compared with field test data obtained in Yakutsk. A satisfactory qualitative agreement was demonstrated, confirming the adequacy of the proposed approach for the design and monitoring of pile foundations in permafrost regions.

The development of the oil and gas industry is solely related to the development of new northern territories of the Russian Federation. The development of deposits in permafrost conditions dramatically increases the cost of construction, primarily foundation work. One of the ways to reduce the cost of construction is to abandon the post-welding heat treatment of welded joints of straight seam welded microwave pipes. The paper presents the results of studies of mechanical properties, corrosion resistance, crack resistance, and fatigue tests confirming the possibility of eliminating excessive heat treatment.