In the article the analysis of the strain-stress state of reinforced concrete statically indefinable beam is presented in the conditions of temperatures below zero by Celsius . Experimental data for mechanical parameters of concrete, temperature efforts in reinforced concrete beams are presented. The influence of temperature efforts to the strain-stress state of normal section of beams is analyzed. The temperature deformation coefficient of reinforcement steel of class A400 remains constant throughout the entire specified temperature range. With decreasing temperature, the value of the coefficient of temperature deformation of concrete decreases. Thus, the value of the temperature distortion coefficient recommended by the norms is overestimated by 40%. This affects to the determination of temperature forces in statically indeterminable elements, as well as tensile stresses in the reinforcement due to the difference of this coefficient for reinforcement and concrete. The resulting temperature forces lead to an increase of stresses in the compressed zone, a crack growth and a decrease in the height of the compressed zone by a factor of 1.2 ... 1.4. At the same time there is a stretched area of concrete above the crack.

A new approach to the determination of tangential torsional stresses for rods of arbitrary cross section, based on simplified assumptions of material resistance, is proposed. Its peculiarity lies in the approximation of rectangular and any complex cross-sections of reinforced concrete structures by breaking them into squares with circles inscribed in them, interconnected into a single monolithic figure in a large circle described around any cross-section. Within each i-th circle, the dependence of the tangential torsional stresses on the distance to the center of the circle in question becomes valid. The maximum stresses according to the proposed method are achieved in the middle of the long sides of the rectangle, which corresponds to their actual distribution. At the same time, this model allows us to remove the question of the need to use special tables for the calculation not only in the elastic stage. It also allows you to separate the stress-strain state in the whole set of circular sections from the additional field associated with the rectangular section. The authors corrected and significantly added dependencies to account for the deplanation of a rod of rectangular cross-section, introduced the concept and suggested dependencies to account for local deplanation. The attention is focused on the physical essence of the longitudinal displacements caused by the deplanation; an analogy is drawn with the elementary displacements caused by shear forces. The proposed method allows to take into account the concentration of angular deformations in the corners and other sharply changing geometric parameters both relative to the cross-section plane and in the direction of the longitudinal axis of the rod. Small i-th circles that fall into the contour of the cross section of the rod serve as “condensing” - it is in them that the stiffening elements and effective values of the parameters of the stress-strain state, which provide the resistance of the cross-section of the rod to torsion, concentrate. Transformational transitions from the cylindrical to Cartesian coordinate systems and the involvement of local coordinate systems, made it possible to simplify the dependencies as much as possible. The division of the calculated parameters into the corresponding components of the stress - strain state provides the possibility of their in-depth analysis.

Cable-stayed structures are simple in assembling, light in weight, safe in maintenance, and often possess the architectural expressiveness. Today’s cable-stayed structures erected in Germany, France, Italy, Japan, Singapore, USA, South Korea, Australia, and other countries are recognized as unique and innovative structural solutions. Unique first-of-its-kind systems and the well-known structures and buildings of all types, which have practical importance and novelty and were marked by the rewards of professional associations or were passed into the top lists of journals, are presented in the paper. But there is no current classification of cable-stayed structures till present time. New classification of cable-stayed structures containing five groups or ten sub-groups of considered structures is offered. It is impossible to present all meaningful cable-stayed structures in one paper but every sub-group is illustrated by specific notable examples. The principal information on the 90 remarkable cable-stayed public and industrial buildings are submitted for consideration and a special table with the indication of country, architects, and year of erection of these structures was compiled first. The existence of such cable-stayed structures as "suspended bridges" of two types is indicated but their description is not given, because it is the subject of analysis for bridge engineers. The 58 references presented in the manuscript will help to obtain additional information.

The problems of numerical calculations of structures for bending are considered. The substantiation of the selected theme of research is given. The numerical calculations of steel I-beams with the subsequent experimental verification of the results are performed. The calculations were carried out in a physically nonlinear formulation, taking into account the actual material deformation diagram. Various conditions for supporting models are considered, including taking into account friction forces. Pure bend models of steel beams were tested. A description of the models, the characteristics of the test equipment, support and load devices performed. The analysis of the results of bending tests of models and comparison with the calculated data is done. The graphs of deformation of models under load with different boundary conditions, obtained from the results of experimental and numerical studies, are given. An estimate of the accuracy of ultimate loads and vertical displacements, obtained by calculation, with respect to experimental data is given.

Employment of wood in housing construction constantly increases. Special interes is observed in modulus housing, in which the most part of construction production, finishing and engineering equipment is performed on factory. Basically, the height of such buildings is limited to 2...3 floors, but sometimes can be up to 5 floors. Foreign experience showes that the number of storeys of such houses can be increased to 7 floors. Structures on a wooden frame can be corresponded to the third degree of fire resistance and C0 fire class. These indicators allowes to build buildings up to 5 floors in height in Russia with their division into fire compartments. The determining factor of number of floors in frame houses is strength and stability of main bearing elements of wooden frame. Significant increase of strength and stability of the wooden racks of the frame achieving with including claddings by shear-resistant mechanical connectors using is shows in studies. The article presents the methodology and results of the study of the critical force for wood ribs, working with claddings in wall panels or bulk modules. To accomplish the task, the composite rods theory of A.R. Rzhanitsyn is used.

The problems of preservation of the object of cultural heritage "water Tower of the lower Vyksa plant" (JSC "VMZ") and the possibility of its restoration and moving to the Central part of Vyksa are considered. The article presents the history of the creation and operation of the water tower, the results of a comprehensive scientific study conducted in 2018, including a full-scale survey, during which numerous defects and damage to metal structures were recorded. The most dangerous of them - slit and deep ulcerative corrosion of nodes and elements of the tower. The results of verification calculations, which showed that the strength and stability of the tower is sufficient, are presented. The article presents recommendations for disassembly, restoration of elements moved to the Central part of the city of Vyksa construction by laser cladding and their subsequent Assembly, which will preserve this unique monument of engineering.

The current realities of the development of projects of new construction and reconstruction of existing buildings and structures are also require taking into account the risks associated with the production of works and subsequent operation. Evaluation of the factors that lead to the need for repair and restoration of building structures, will allow them to pay the necessary attention and take into account these factors in the design and conduct of work. The article presents numerical data, as well as the results of the analysis of the reasons that led to the need to restore/strengthen the reinforced concrete structures of existing buildings and structures, new, under construction, and in operation (the analysis is carried out according to 576 real objects that require repair and strengthening of building structures). Statistical processing on specific types and groups of objects is carried out, the corresponding conclusions are drawn.

The classification of methods of protection against progressive collapse in three main categories: secondary protection measures, indirect design and direct design is considered. The analysis of the requirements for the protection of buildings and structures from progressive collapse in the legal and regulatory documents of Russia and the countries of the European Union. The specific provisions of the Russian and European normative documents on the design of stability of bearing structures of buildings and structures against progressive collapse are considered. Namely, a comparison of the requirements for the definition of load combinations, the value of the special load, to the parameters of the zone of limitation of local destruction in the normative documents of Russia, the USA, the EU countries. The analysis of experimental and technical studies of building structures under special influences is carried out. Most of the experimental studies were carried out on reinforced concrete, steel and composite structures, little attention is paid to the study of stone and wooden structures in this area.

The features and stages of formation of the planning structure of Voronezh in connection with changes in architectural and artistic, space-planning, compositional and structural characteristics of the period of XIX-early XX centuries. The attention is focused on the importance of the grandiose all-Russian town-planning reform of 1763 and the regulatory documents developed by The Commission of buildings of St. Petersburg and Moscow, which could significantly improve, through the introduction of "exemplary projects", architectural and artistic qualities of the building and fire safety of the city. Different types of Voronezh development are given in accordance with the stages of the evolutionary development of the spatial-planning structure of the city.

Within the framework of the concept of sustainable urban development, the problem of forecasting the parameters of the air environment is being solved and the impact of the processes occurring in urban areas on the atmosphere is assessed. It is shown that among the main methods for solving this problem is the creation and development of information systems for monitoring, forecasting and warning about the state of the air environment. It has been established that complex information systems are developing most actively, allowing one to consider physical and chemical processes on a fairly large spatial scale, as well as to predict the state of the air environment of the city as a whole. The possibilities of using these systems to study processes in relatively small amounts of air are limited. The authors proposed a schematic diagram of a local information system for predicting the dynamics of the air environment. An algorithm for the implementation of the proposed approach. The results of the development of the measuring component of the local information system are considered in detail. The results of measuring the dynamics of the concentration of carbon monoxide, nitric oxide 4, and sulfur dioxide in the ambient air of residential buildings adjacent to the territory of the Oryol CHP during the day are presented. It is shown that the dynamics of the concentration of pollutants in the air during the day, obtained experimentally, corresponds to modern theoretical ideas about the nature of the distribution of the pollutants in the air. On the basis of the obtained results, it was concluded that the developed measuring component of the local information system for forecasting the dynamics of the air environment was adequate.

The study is based on identified archival and printed sources, full-scale studies of the author, which allow more reasonably reconstruct the imaginative structure of lost noblemen and merchant estates in the field of reconstruction of their architectural and spatial organization in the territory of the border region of Russia. The basis of the study is the study of topography and physical-geographical types of terrain, characteristic of the Kursk region. The scientific novelty of the research is connected with the conduct of the author's expeditions to identify signs of existence and a full-scale survey of a number of surviving manor complexes, which did not previously attract the attention of researchers. Of particular importance is the identification of archival and printed sources, which allow more reasonably reconstruct the imaginative and material structure of the lost elements of the nobility and merchant estates. The special significance of the comprehensive research work is due to the ability to fill the gaps in the study of important pages of the history of national and regional Russian culture, reflected in the formation of regional features of building techniques and imagery of architectural ensembles of the Kursk region's estates.

The technology of erection of reinforced concrete floors with non-removable core formers during the overhaul of buildings with the replacement of wooden floors. The use of net formers allows to reduce the consumption of concrete, reinforcement, reduces the duration of construction and energy costs. The technological features of the device of overlappings with cylindrical core formers, spherical and elliptical in the form of flat polystyrene plates are established. Adapted technology for the construction of floors to the conditions of capital repairs of buildings. The technological sequence of work production, taking into account the constraints of the conditions of the working areas, is given.