The paper attacks the problem of steel redundant structures reliability. In calculations the probabilistic method of limit equilibrium is applied. All possible mechanisms of structural failure are considered. The influence of each section on the work of the frame as a whole is taken into account. Stochastic strength and load characteristics are used in the calculations. The proposed method of calculation allows to obtain structures with a given reliability. The calculation provides an opportunity to take into account the existing reserves of frames. The numerical example uses the logic of probabilistic transformations. The graphs of specific contributions of individual sections and the most probable mechanisms of destruction are presented. The probabilistic method takes into account the correlation between the individual mechanisms of destruction. The developed method determines the limiting moments, but it is allowed to take into account the action of the longitudinal force. In this example, the task was to align the impact of the frame sections without reducing the specified reliability, but it is possible to obtain a design with the same specific contributions, which is most economically justified. Specific contributions are increased or decreased as necessary to obtain a design with equal probability of failure. In the design, the influence of destruction individual mechanisms is used, because the cross sections of the beam span or floor column do not change from the design conditions. The method provides an opportunity to obtain more optimal designs and the use of modern software systems for static calculation. Recommendations for the design of these structures have been developed. It is proposed to use the reliability coefficient of redundant steel structures.

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The article is devoted to determining of the thermal reliability rates of CFS wall panels based on three thermo-technical failure criteria - reduced heat transfer resistance, exceeding the values of the temperature difference between the reduced temperature of the inner surface of structure and internal air temperature above the permissible temperature values by the sanitary requirements and criteria of reduction of local values of the inner surface temperature to the temperature of vapor-liquid condensation. With increasing coefficient of variation of thermal conductivity from 2.28% to 20%, the probability of refusal of wall panels of light steel thin-walled structures, under the criterion of the specified heat transfer resistance, is increasing from 9,85´10-7 to 0,015 respectively.

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Concept of bulk material and complexity of storing it are explained. The dependence between the physical and mechanicalproperties of the loose material and type of construction in which it is stored. Structural elements considered silos and siloswith conical and flat bottom are described. The common characteristics of metal silos for bulk materials are given. The classification of metal silos by type of housing design is given. The advantages and disadvantages of silos are described.The possibility of storage of bulk materials in cylindrical shells is analyzed depending on the type of construction. The history of occurrence of structures of spiral-fold silos is considered. The set of equipment for the construction of the housing ofthe spiral-fold silos is given, the step-by-step process of formation of the folding lock and features of the installation processare presented. The analysis of the structure is made and the advantages and disadvantages of spiral-fold silos are determined.