Building Failures in Permafrost Regions

Deformations of buildings in permafrost regions are inexcusably numerous, especially in Russia. "The percentage of dangerous buildings in large villages and cities in 1992 ranged from 22% in the town of Tiksi to 80% in the city of Vorkuta, including 55% in Magadan, 60% in Chita, 35% in Dudinka, 10% in Norilsk, 50% in Pevek, 50% in Amderma, and 35% in Dikson" (Kronik 2001; ACIA 2005). Hundreds of buildings were demolished or went through serious reconstruction (Ilichev et al. 2003).

There have been many attempts to understand the causes of such numerous failures. Bondarev (1957) was possibly the first who classified these causes as poor assessment of soil conditions at the site, mistakes in choosing foundation design approach, mistakes in design, poor construction quality, and poor maintenance.

Many failures were caused by infiltration of hot water from broken heating pipes, which resulted in the formation of deep thaw zones and severe differential settlement (Kuriachiy and Illarionov 1959; Ilichev et al., 2003; Alekseeva et al. 2007). Poor drainage and ponding of water in crawl space also cause damage (Goncharov et al. 1980; Johnston 1981). Existing building codes on foundation design in permafrost regions are focused on a separate building, and do not consider changes in permafrost conditions associated with the development of the entire area with streets, utilidors, and storm canalization (Ilichev et al. 2003).

Documented failures of building foundations constructed according to the passive method, which are attributed to changes in permafrost, very often do not directly relate to air and permafrost temperature. Such foundations failures are not caused by permafrost warming but by climatic effects on foundations material in the active layer and in a crawl space, unaccounted for thermal stresses, and low freeze-thaw resistance of concrete in piles. Concrete piles are the most widely used foundations in the Russian permafrost region. As was found in Norilsk, Yakutsk and some other places, the upper parts of piles and their connections with concrete grillage deteriorate, and cracks in walls are often caused by crushing of the upper parts of piles. Such processes can not be directly attributed to changes in permafrost, although wetting and drying of soil of the active layer are factors contributing to fast weathering of concrete (Goncharov et al. 1980).

Thus, there is no direct correlation between failures of structures and their l ocation. Numerous failures have occurred both in continuous and discontinuous permafrost zones, and at sites with different soil conditions and permafrost temperatures. Some deformed buildings were constructed in accordance with the passive method, while others were built to accommodate thaw settlement.

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