Many buildings are exposed to special effects of high intensity. When calculating reinforced concrete constructions both for special emergency loads and for seismic loads, the development of plastic strains in reinforcement is supposed just at the design stage. The experimental investigation of plastic deformations influence of the stress-strain state of normal sections of bending reinforced concrete elements has been made. According to the results of experiments, it has been found, that the hypothesis of plane sections is not observed in all cases. The approximation of deformations graph along the cross-section height by the bilinear function, variable during the load process, i.e hypothesis of bilinear sections, is more accurate. The dependence of coefficient A of the hypothesis of bilinear sections on the coefficient of plasticity for reinforcement deformations has been determined based on the results of numerical calculations of beams with symmetric reinforcement and beams without compressed reinforcement in a finite element software package Abaqus. The comparison of obtained numerical results with experimental data has been made, which has shown their satisfactory convergence. The maximum deviation does not exceed 13 %. The assessment of influence of coefficient of hypothesis of bilinear sections on the limit value of coefficient of plasticity for curvature, corresponding to the beginning of the destruction of compressed area of concrete is given.

The use of numerical models to assess the resistance (load bearing capacity) and serviceability of new and existing structures is one of the most important achievements of recent decades for civil engineers. The numerical model, like any other model, has uncertainties that need to be established and taken into account when ensuring the structural reliability. At the same time, the statistical characteristics of the uncertainty of numerical models remain the least studied. The purpose of the study is to develop and scientifically substantiate the design based on numerical models of loadbearing capacity. The object of the study is the parameters of numerical models and statistical characteristics of the uncertainty of the numerical result. The main objectives of the case study include: (i) analysis of the sensitivity of the results from variations in the parameters of numerical models; (ii) verification of the parameters of numerical models based on experimental data; (iii) calculation of statistical characteristics of the uncertainty of the numerical model, which are expected to be used in the future in the development of the safety format and the normalization of the values of partial reliability factors.

The influence of the step of the transverse layers of five-layer slabs of cross-glued wood (CLT panels) on the deformation and distribution of the resulting normal and tangential stresses in the layers of the structure is considered. The research was carried out in the SCAD+ computing complex by the finite element method (FEM). As a result of the conducted research, the dependences of deflection and stresses on the variation of the pitch of the transverse lamellae of a cross-glued plate consisting of 5 layers are obtained, systematized and clearly shown. It is revealed that with increasing distances between lamellae in transverse layers, deflections increase and the normal stress along the span increases significantly. At the same time, the stress increases slightly in the middle layer, which indicates that the upper and lower layers, working for compression and stretching, respectively, perceive the main load during bending.

The paper considers the influence of various factors on the actual length of clamps in the design of sections of linear bending reinforced concrete elements. The aim of the work is to determine the degree of influence of clamps of various configurations and other factors on the length of the clamp at various cross-sectional dimensions of a linear bending element. The obtained data and dependences make it possible to obtain the most effective solutions for reinforcing inclined sections with minimal cost. The calculation-analytical research method was used, based on the analysis of the results of calculations for  various  types of transverse reinforcement, the ratio of the diameters of the longitudinal and transverse reinforcement, the values of the protective layer, the radius of the bend of the clamp and the dimensions of the section. An expression is proposed for calculating the actual length of the clamp, depending on the dimensions of the section, the coefficient of reinforcement and the thickness of the protective layer, taking into account the mandrels used.
Graphs of the change in the length of the collar for various section sizes b×h from 20×40 cm to 55×80 cm and with a reinforcement coefficient of 0.1%≤μ≤3% have been obtained. The graphs show savings in the length of the clamp from 6.7-7.4%, when using working fittings Ø6, to 12.2-37.9%, when using working fittings Ø40. The dependencies of strength reduction under conditions of inaccurate binding of the working longitudinal reinforcement to the collars are analyzed. The data obtained indicate a decrease in the strength of normal sections of beams from 0.33% to 10.78%. The paper considers the influence of various factors in the design of the sections of linear bending elements on the actual length of the clamps in accordance with accepted standards. Thanks to the obtained data and dependences, it is possible to refine the consumption of transverse reinforcement in beams for its more economical use.

The article considers the process of formation of evaluation criteria in the course of operation of the category of technical condition of reinforced concrete columns, crossbars, beams and trusses. Criteria for limited serviceability and emergency conditions were determined using calculations using the method of limiting forces, taking into account the bearing capacity reserves laid down in the design. As an example, one characteristic design defect for each type of structure is considered. The establishment of criteria for defects that were not considered in the calculations was carried out by analyzing and studying the characteristic defects of building structures of buildings and structures based on data from previous studies, as well as based on the results of consideration of other regulatory and technical documents. The criteria given in the final table were proposed for inclusion in the second edition of the revision of GOST 31937–2011 «Buildings and constructions. Rules of inspection and monitoring of the technical condition».

The paper presents a new structural solution of the precast-monolithic frame for prefabricated residential and civil buildings of various storeys manufactured from prefabricated industrial reinforced concrete elements. The precast frame structures include L-shaped and inverted Ushaped precast elements, installed in the longitudinal and transverse directions and forming a frame, hollow-core slabs and bracing perforated beams of the outer contour, on which fencing non-bearing wall structures are supported within each storey. The computational model of the precast-monolithic building frame was developed using different degrees of discretization at different stages of the analysis. This allowed to obtain both a general picture of structural system deformation in the limiting and over limit states caused by special and emergency actions, and a detailed picture of the stressed state in concrete and reinforcement of structural elements before and after cracking. 
The paper provides the results of the comparative analysis of the effectiveness of application of the proposed structural system in the mass construction as compared with the applied constructions of large-panel buildings. It has been shown that the application of the proposed structures of panel-frame elements allows considerably reduce the material capacity, cost and transportation expenses of the reinforced concrete frame by up to 30 %, ensuring the mechanical safety of the building.

Today, in the field of urban planning, the problem of preserving the recreational potential of natural territories, in particular the territories of historical and cultural landscapes, and the creation of urban public spaces in symbiosis with the natural environment in these territories is becoming increasingly important. In the theory and practice of urban planning, there is no scientifically based approach to the restoration and ecological reconstruction of the territory of historical and cultural landscapes from the standpoint of their sustainable development, as a result of which the territory of protected meadows in Suzdal has been in an environmentally unfavorable state for a long time with signs of degradation of landscape components. The purpose of the planned ecological reconstruction of urban landscapes in the city of Suzdal is to ensure a dynamic balance between the natural and urbanized environment. One of the ways to achieve such a balance, as well as to preserve the environment and improve the well-being of the local population, can be the development of ecotourism as a tool to solve the problem of congestion in the central part of the historical settlement due to the seasonal influx of tourists. In order to reduce the anthropogenic load on the historical environment of the city, improve the welfare of the population, get acquainted with the local culture and  the natural environment, it is important to separate tourist flows in different directions in green spaces along the river along organized ecological trails. During the socio-diagnostic research of the territory of historical and cultural landscapes, the dynamics of the transformation of the territory of landscapes were established and an assessment of the ecological state of the reserched territory was carried out, revealing, at the same time, the possibility of  their restoration. The conducted sociological survey determined the attitude of residents and tourists of the city of Suzdal to this problem as an interested social group of the population.

The problems of prefabrication, cost-effectiveness, strength and energy efficiency of  buildings of residential and civil architecture are becoming especially relevant at the present time, due to the need to quickly restore the destroyed cities and villages in the newly annexed territories. For the purpose of an experimental proposal for a residential building project based on the concept of multicomfort, an analysis of the development of industrial construction methods was carried out. A review of the evolutionary development of industrial housing construction made it possible to identify its advantages (speed of construction, low cost, simplicity of design solutions, etc.), disadvantages (low quality and comfort level, standard stamps, etc.) and ways to eliminate them (increased comfort, energy efficiency, development new constructive solutions, artistic expressiveness, planning variability, etc.). The authors propose the development of a project for a prefabricated residential building based on innovative frame-type panels manufactured in the factory. These structures are quickly mounted on the construction site, they are characterized by increased rigidity, survivability and material consumption. This constructive system provides an opportunity to create flexible architectural and planning solutions with a variety of plastic shapes of the building. Energy efficiency and multicomfort environment of a residential building is achieved by the orientation of the building on the designed site, the use of insulating materials and glazing (reduction of heat loss and noise protection). The shape of the building also ensures the thermal comfort of the yard space. Wind currents are broken by protruding and sinking architectural elements, creating complex and meaningful compositional connections. The use of new industrial structures allows, using the principles of energy-efficient design, to increase the level of comfort and efficiency of a residential building, solve the problems of viability and quick erection of buildings, and create an expressive architectural and artistic appearance of the residential environment.

The spatial organization and regulation of human activity through territorial planning is a very urgent problem for many countries of the world. The issue of the optimal network of population resettlement has always been acute for Russia for a number of reasons, some of which were taken into account in the course of the administrative-territorial reform. In this aspect, the determination of the structural and dynamic characteristics of the settlement network is becoming increasingly important. The article deals with methodological issues of studying the regional spatial structure of the agglomeration. Modeling builds a number of levels with the spatial distribution of the population by function, by the potential and ability of the territory to implement the considered settlement options. This hierarchy represents the different sides of the interaction in accordance with the selected parameter. The constructed layers are a convenient tool for determining the initial agglomerations and promising growth points of the region, the development of which will stimulate the optimal use of the territorial potential, as well as increase the economic and investment potential. The described approach to the study of the spatial structure of the agglomeration can be in demand for sound territorial and urban planning and management, for an effective policy of regional development, etc.

The article discusses the process and significance of a multi-criteria assessment of the territory to ensure its sustainable development, as well as the choice of renewable energy sources (hereinafter referred to as RES) and their location in terms of preserving the ecological potential of the landscape of the territory of the subject of the Russian Federation. The key feature is the determination of the impact of RES on the ecological potential of the territory due to the multicomponent components for evaluation. It is known that one of the advantages of renewable energy is to reduce the negative impact on the environment, however, different types of renewable energy have different effects on the natural system of the territory, both direct and indirect. A comprehensive assessment of the territory of a constituent entity of the Russian Federation is proposed as a tool that allows integrating various types of information on the state of the potential of the territory for the use of renewable energy sources, the ecological landscape, anthropogenic load and other data into a single system for a qualitative spatial analysis of the regional system.

Issues related to improving the quality of the operational properties of reinforced concrete and concrete structures by introducing discrete reinforcement - fiber reinforcement are topical tasks of building materials science. The aim of the study was to obtain high-tech concretes with increased flame retardant properties by introducing an optimal combination of fiber reinforcement components. The change in the compressive strength of concrete after fire tests, depending on the percentage of polypropylene fiber, is analyzed. The TSP-27-25 program, developed at the Tver State Technical University, which allows modeling various concrete compositions, was used in the calculation of the control compositions of fiber-reinforced concrete. It has been established that the addition of fiber makes it possible to increase the fire resistance of concrete with an optimal amount of it. An assessment of the strength characteristics of the studied samples after fire exposure is given. The influence of polypropylene fiber content on the nature of concrete destruction is investigated.