The paper is devoted to purism (Latin purus − "pure, strict"), the second creative direction in the design and social activity of S.-E. Jeanneret-Gree (Le Corbusier, 1887−1965), the outstanding French architect. It is one of the most popular trends in modern painting and architecture in the early 20th century.
The paper considers this style in detail. The most striking elements of French purism were firstly tested in the design of the villa belonged to Raul Albert La Roche (1925−1928), a Swiss businessman and collector of paintings.

Purpose: The aim of this work is to determine the structural components of the natural landscape of Saratov and comprehend its role and place in the formation of this historical city.
Research findings: Based on the analysis of related research results, the forwarded statements determine further research. The detected key elements of the landscape provide the expressiveness and interrelation of natural and anthropogenic subsystems in the city. Two levels of the city formation are distinguished together with their structure and influence on the city of Saratov. Research findings: Based on the analysis of related research results, the forwarded statements determine further research. The detected key elements of the landscape provide the expressiveness and interrelation of natural and anthropogenic subsystems in the city. Two levels of the city formation are distinguished together with their structure and influence on the city of Saratov.

The paper is devoted to novel approaches to the design of Arctic cities against global climate changes in permafrost regions. The paper studies demographic, ethnographic and tourist aspects of the city design in the Arctic zone of the Russian Federation.
Methodology/approach: The development of new approaches to design and settlements in the Arctic zone of the Russian Federation. The methodology and theory of this study is based in research of urban planners and architects engaged in problems of settlement in the Far North and design of modern residential and public buildings in the Arctic zone.
Research findings: It is shown that approaches to the design of the urban environment and in the central and southern regions of our country are different. As a result, the main approaches are identified for Arctic cities.
Practical implications: The proposed approaches can be used by urban planners and architects for the creation of new architectural complexes in the Arctic zone of the Russian Federation.

The article discusses problems of concept genesis and development of affordable housing in Russia, Europe, and the USA in the 5–18th centuries. Affordable housing plays an important role in the quality of life and social integration. Affordable housing originates from the history of European civilization and Christian axiology, where communal living and housing for the poor are determined.
Purpose: The following types of housing are studied: bursas (5−15th centuries), almshouses (10−11th centuries), Fuggerei (16th century), Shaker (17−18th centuries) houses. Their master plans and facades are studied herein. Population categories for which housing is assigned are indicated as well as the period of residence and owners.
Research findings: Affordable housing is built by private individuals. The housing development is influenced by the policy pursued by their governments and external factors such as socio-economic, demographic, political, administrative, legal conditions, which determine the role, goals and characteristics of housing. Housing types are determined according by the following parameters: residence duration, owners, residents, and their activities.

Saratov’s classicism is the first stage of its capital construction. It plays a major role in the formation of the architectural environment of the historical center. Classicism also influences the formation of the central part of the city. The article considers the processes of organization and self-organization of buildings in Saratov during the period of Classicism.
Purpose: Identification of classicism buildings in Saratov.
Methodology/approach: The main levels of scientific knowledge are accepted: a theoretical method involving the study of documents describing the architecture of classicism, a practical method to determine the elements of the environment, their harmony, and the systems analysis of these documents.
Research findings: Regional properties of Saratov are studied for the period of classicism.
Value: A study of harmony in the architectural environment of the historical center Saratov.

Calculations in software systems based on the finite element method (FEM), performed with account for genetic nonlinearity, i.e., assembling, are not feasible for a number of construction problems. In particular, in buildings made of factory-made and cast-in-place concrete, the latter is gradually involved in deformation and external load processes. In reconstructed buildings, during the increase in the element cross-section (e.g., reinforced concrete or metal casing), the reinforcing and reinforced materials are also involved in deformation and external load processes at different time. As a result, there are initial stresses and strains in the "old" part of the element by the time its "new" part installation and strength gain. At the same time, in the reinforcing material or cast-in-place element, the stress-strain state is zero until the additional load is applied.
Thus, during the structural analysis, a change in the finite element stiffness is required. But FEM software systems have no finite element capable of changing (increasing) the stiffness. This determines the relevance of the developed algorithm for the structural analysis of factory-made and cast-in-place concrete buildings using the parallel FEM.
Purpose: The aim of this work is to improve the parallel FEM and develop a calculation algorithm based on it.
Research findings: Based on the parallel FEM, the calculation algorithm is proposed for factory-made and cast-in-place concrete buildings. The proposed algorithm accounts for the structural properties of such buildings, including the gradual involvement of different-aged materials in the deformation process. Using the proposed algorithm, the structural analysis is conducted for the reconstructed system, in which the finite element is replaced by the parallel element, and the hinge coupling of elements is simultaneously replaced by a rigid one.

The reliability evaluation of gas pipeline systems is one of the most important tasks, since the safety of gas supplies determines the reliable operation of the whole system.
Purpose: This paper presents the evaluation methodology based on the risk acceptance criteria established in accordance with the current rules and standards.
Methodology: A three-component methodology is used to evaluate the reliability level of gas pipeline systems. It is implemented by creating a model of failure consequences, which accounts for environmental conditions and pipeline properties. Acceptable probabilities of the pipeline failure are determined using the risk theory. Based on these data, the model is designed to assess the gas transport reliability in the pipeline system with regard to failure probabilities and hydraulic characteristics.
Research findings: The reliability level of the system is determined using the acceptable failure probability. The obtained reliability is compared with that of the real pipeline system. The best procedure is proposed to maintain and improve the system reliability.

Purpose: The aim of this work is to analyze competing risks of engineering system failure using nonparametric prediction.
Methodology: Two statistical methods are used to tackle the problem of the pipeline integrity. Nonparametric prediction is applied in the first one. The main attention is paid to the possible failure of the pipeline section due to a specific threat in terms of competing risks. The second method contains the analysis of the entire pipeline system. The focus is on rupture incidents, that provides the real data on the lifecycle of the pipeline section.
Research findings: Nonparametric prediction is used to analyze competing risks of the pipeline failure. The lower and upper probability boundaries and survivability functions and competing risks of the pipeline section failure are introduced for a future ground section of the pipeline, which can be failed as a result of rupture.

The paper studies the load-bearing capacity and stability of reinforced concrete composite frame without collar beams during linear and physically nonlinear operation of its materials under static loading.
Purpose: The strength analysis of a reinforced concrete frame without collar beams using the coefficient of structural strength in the linear calculation and use factor by bearing capacity determined by the limit surface of elements, as well as linear and physically nonlinear stability based on the limit repulsion of the system.
Methodology: The computational substantiation of the bearing capacity and stability of the reinforced concrete frame at different stages of materials performance, is carried out in the Ing+2021 MicroFe program with the proposed finite element spatial model.
Research findings: The structural strength and bearing capacity are calculated for reinforced concrete composite frame without collar beams during linear and physically nonlinear operation of its materials under static loading.

Purpose: Argumentation of necessity of special protective system design to protect structures in seismic zones and remote areas from specific loads. Such protective system combines seismic isolation and internal force control systems.
Research findings: Restrictions of long-span structures construction are reviewed. Such restrictions are caused by building conditions embodied in National Building Codes and Standards. Combined and separate use of seismic isolation and internal force control systems is a critical specific load protection. Present inventions and experience in the field of seismic isolation and internal force control systems are reviewed.
Value: The article determines problems of protective system design based on the control for combined strain-stress state.

The material distribution in structures is an urgent scientific and technical problem. Corrugated and prestressed steel structures are efficient and reliable.
Purpose: The aim of this paper is to study the operation of steel I-beam with a thin corrugated wall, prestressed by flange drawing.
Methodology/approach: Finite element modeling of beams with corrugated and flat walls (models with flat wall, transversely corrugated wall, downward corrugation at an angle of inclination 20 degrees, ascending corrugation at an angle of inclination 20 degrees). The proposed method is used for prestressing the lower beam flange using negative temperature effects. Numerical experiments in LIRA-SAPR software allow to obtain the stress distribution isofields and deformation patterns. A comparative analysis of the stress-strain state.
Research findings: The normal stress distribution over flanges of corrugated beams with and without prestress under the external load has low difference. Prestress produces significant deflections of structures and the greatest deflection of the beam with ascending corrugations.

Water flow rates calculated by using deterministic models and methods do not describe the real variability in the water supply operation. This problem can be solved by mathematical simulation. The stochastic nature of the water consumption process implies involves random variables with certain distribution laws describing the main process components, namely intensity, duration and frequency.
This paper discusses the mathematical simulation of the duration and frequency of water consumption by the most common types of water dispensers (kitchen sink and bathtub faucets (shower cubicle), toilet bowl with flush tank, washing machine and dishwasher).
Purpose: The aim of this work is to evaluate and substantiate theoretical laws of the water consumption by the most common types of water dispensers as well as the frequency (probability) of their daily use.
Research findings: The duration and frequency are determined for water consumed by various water dispensers using water supply systems of buildings. The empirical data are analyzed. Mathematical simulation method is proposed and justified for the water consumption process.

Purpose: The aim of this work is to develop fluorine anhydrite-based ceramic materials and engineering concept for their production and identify the conditions for the ceramic body formation and strength improvement.
Methodology/approach: Acid fluoride without aditional processing and ash from thermal power plants are used in the experiment. Sodium silicate solution and the aluminum powder are introduced in the melt for the mullite formation. The phase composition is investigated on a Shimadzu XRD-6000 Diffractometer. Clay is dried to prepare the mixture and then it is ground in a jaw breaker and co-milled with the specific amount of acid fluoride.
Research findings: Granular and piece ceramic wall materials with the required properties are obtained. Drying and firing conditions and the main performance characteristics are determined herein.
Practical implications: Construction and technical characteristics of acid fluoride are detected for the ceramic material production, the proposed methods can be used for ceramics modification, allowing to reduce expenditures per unit of output for mineral raw materials.
Originality: Process conditions are determined for the ceramics production, and dependencies are suggested to control the composition and properties of granular and piece ceramic wall materials.

Today, the use of environmentally friendly materials is becoming increasingly important. The construction of energy-saving buildings with enclosing structures made of insulated profiled timber, is one of the most promising areas in low-rise construction.
Materials having minimum negative impact on the environment during their operation, include new construction insulation materials based on peat-vermiculite granules. The paper studies the main physical properties of wooden exterior walls made of profiled timber, in which peat vermiculite is used as insulation, thermal conductivity of which ranges from 0.05 to 0.06 W/(m·K). For this purpose, numerical simulation is performed for the heat-mass transfer in wooden enclosing structures made of insulated timber with three different connector options.
The temperature and heat flow distributions are obtained as a result of modeling stationary thermal conductivity processes in timber structures. It is shown that plywood connectors do not affect the thickness temperature distribution in wooden walls with peat-vermiculite insulation. An increase in thermal conductivity of insulation has no significant effect on the temperature difference along the connector axis or outside the region of its temperature influence.
It is found that the thickness of the peat-vermiculite insulation layer should be at least 0.176 m to ensure the compliance with the main requirements for thermal protection properties of enclosing structures in the climatic conditions of Tomsk. The greatest heat loss with a minimum insulation thickness is observed for the wall made of profiled insulated timber with T-shaped connectors. A high-strength timber with the additional central lamella has the best thermal protection with the lowest insulation thickness.

The work is devoted to the creation of high-strength ceramic materials with technogenic waste fillers.
Purpose: Investigation of the ceramic and composite production based on chemical and metallurgical wastes to create new types of high quality constructional ceramics.
Methodology/approach: The use of refractory clay with the addition of high-iron bauxite sludge as the main raw material. Bauxite sludge functions in compositions with aluminosilicate raw materials at burning at 1100 to 1200 °С, reduce to sintering due to its melting at 1150 °С.
Research findings: Refractory clay compositions with red mud in the amount of 20 to 50 % at the burning temperature of 1050 °С, provide the ceramic formation possessing the compressive strength 1.3 to 1.5 times higher than that of clay samples without additives, i.e., 91 and 122–132 MPa, respectively.
Value: The obtained ceramic compositions based on red mud determine a production of high-strength anorthite and anorthite-helenite ceramics using dry pressing.

Purpose: The aim of this work is to substantiate recycling of anhydrite raw materials for the production of silicate products and the development of methods for preparing source materials, compositions and process modes.
Methodology/approach: Selection and research of basic materials, methods of their preparation for the production of silicate products; justification of process methods and assessment of quality parameters of materials with the required properties.
Research findings: The possibility of utilizing acid fluoride during the synthesis of calcareous-siliceous binder used to produce silicate bricks during autoclave processing. The obtained sand-lime brick samples possess the following physical and mechanical properties: 1750 to 1900 kg/m³ average density, 10 to 12.5 MPa compressive strength, 16 or 17 % water absorption. The samples meet the requirements for sand-lime bricks, namely strength, density, water absorption and correspond to grades 100 and 125.
Practical implications: The process modes of autoclaving are detected and the main operational characteristics of sand-lime brick are determined. Methods proposed for preparing raw materials and process conditions of silicate wall materials allow solving environmental problems and saving natural limestone raw materials.
Novelty: Sand-lime brick production is based on anhydrite raw materials; suggested dependencies make it possible to control the composition and properties of silicate materials.

Rebar coupling connections are widely used for joints, and it is necessary to get information about the stress field distribution on the coupling surface at uniaxial tension to characterize operation of such joints.
Purpose: The aim of the work is to study the stress-strain state of rebar connections under tension, full-scale junctions of the type A500 rods, and the deformation influence on the steel microstructure of grade С1020.
Methodology: Non-contact three-dimensional imaging system VIC-3D and digital image correlation and tracking for studying stress-strain state of rebar connection; transmission electron microscopy for studying the steel microstructure.
Research findings: Load-displacement curves are suggested for the valve coupling, and three deformation stages are identified: 1) elastic deformation of the coupling connection, 2) parabolic hardening, 3) preceding the coupling connection destruction. The analysis of the strain field distribution on the coupling connection shows that at any time, plastic strain localizes in certain zones of the sample. The stress field evolution on the coupling connection correlates with the indicated deformation stages. The compliance of the rebar joint made of seamless hot-deformed tube with an outer and inner diameters 51 and 32 mm, respectively, made of С1020 steel grade, induces 500 MPa stress in the normal section of rebar under the tensile axial load.
Value: It is shown that during uniaxial tension of 0 to 5 %, perlite fractures, which is accompanied by further polarization of the dislocation structure. The internal stress amplitude increases and at 5% tension, far-range stresses grow as compared with those induced forest dislocations. The main contribution to far-range stresses and their change at 5 % tension is made by the elastic component, that promotes to the microcrack formation.

Pulse-periodic loads on structures are one of the most dangerous for the their stress-strain state under dynamic load.
Purpose: The aim of the work is to analyze the dynamic deformation of linear-elastic frame structures under pulse-periodic loads.
Approach: It is found that a simple frame structure with additional concentrated masses affects the loading parameters (length, shape and pulse frequency). The analysis is given to physical characteristics of the deformed structure and its dynamic response under the pulse-periodic load.
Research findings: Prerequisites are formulated for an unfavorable (from the position of VAT parameters) combination of the load and structural parameters.