Особенности проектирования и строительства зданий в сейсмоопасных районах с многолетнемерзлыми грунтами

Abstract

Purpose: Analysis of accumulated experience in the design and construction of buildings in areas with permafrost and seismic activity. Methods: Statistical and analytical methods have been applied. Results: The areas of distribution of both permafrost soils and seismics on the territory of Russia are considered. The review and analysis of the principles of construction on permafrost soils is given. 2 main methods of preserving the foundation soils in a frozen state using principle I of construction and 3 combined options when pairing a pile foundation with a ventilated underground, filling and cooling devices are considered and analyzed. The conclusion is made about the construction using principle I, where a pile foundation with a high pile grillage and a ventilated underground is preferred as a foundation, since the piles of this foundation act as a flexible connection between the aboveground part of the building and the base. In case of seismic impact, this foundation perceives the action of vertical and horizontal seismic loads, as well as the action of the tipping moment. In the case when it is impossible to keep the foundation in a frozen state under buildings, it is necessary to use principle II, which is implemented due to the coefficient of safety and rigidity of building structures, as well as pre-construction measures aimed at thawing, pre-compaction or partial replacement of natural subsidence soils, increasing the depth of foundation laying or regulation of the thawing zone due to planning decisions or applications of devices for heat removal. It is revealed that spatial foundation platforms are effective earthquake-resistant structures of foundations on permafrost soils using principle II in conditions of seismic activity. The analysis of the design experience on permafrost soils in seismically active areas is carried out. Practical significance: It is proposed to use principle I of construction of earthquake-resistant buildings on permafrost soils (in cases where permafrost preservation is possible).