Ventilation Shafts Freezing Protection Under the Influence of Negative Temperatures

In the winter operation process of the subway ventilation shaft freezing of the lining may occur, which during the long-term operation leads to its increased wear or even destruction with the soil release into the shaft. This article is devoted to the development of the foam glass concrete thermal insulation jackets design and methods of their construction, which allow carrying out ventilation shaft lining insulation along with its strengthening. In the course of the research, design solutions were developed, the necessary material properties were determined, and mathematical and physical modeling of the structure was performed. The studies were carried out for the conditions of St. Petersburg, but the experience gained in the framework can be used in ventilation shafts freezing protection operated in more severe conditions.