Abstract. Influence compliance of node connections are not taken into account fully in the existing calculation methods. Basically, this is because of insufficient three-dimensional interference knowledge of elements of thin-walled steel frames. In practice, the structural analysis of the LSTC is usually made with the help of design diagrams with articulated or rigid joints connection elements, therefore, real behavior of structure is not taken into account, as the compliance units may lead to substantial redistribution efforts. Researches in clarifying the design diagrams allow to calculate the steel thin-walled structures with more accuracy and to improve the economic efficiency of design solutions. Thus, the purpose of the study is to determine the qualitative and quantitative characteristics on the basis of experimental and numerical studies that affect the loss of local stability in joints, taking into account the compliance of node connections.

Abstract. In general, the majority of modern apartment buildings are rather high. Altitude of such structures attains 50 meters. It is clear that for such high structures every extra meter of elevation costs a lot. For this reason, architects are trying to avoid adding attics above the last floor of the buildings. However, attic is not only an architectural element. It is an important part of the thermal control process of the entire building, especially of the apartments located on the last floor. In this article, construction of airways under the roof is suggested and discussed in detail. Airway acts as an attic, but has a significantly lower construction cost due to the lower height. Application of this technology allows providing comfortable microclimate on the living quarters in an economical way.

The presence of ice crusts and icicles on roofs is an urgent problem since they influence on the people safety and property which could be situated unde roof cornices. There are a lot of methods to stop icicle formation on the roofs. At present article is considered an efficiency of an unsteady airway. The unsteady airway can change its section area depending on the wind speed. Such a constriction allows entering into the attic a big volume of cold air. At that сontribution is find a speed of snow melting on the roof featured by the unsteady airway. Speed of the snow melting influence the speed of ice crusting. By estimating these factors can be made a conclusion that the unsteady airway helps to reduce a quantity of ice dams.