The article deals with wooden merchant estate buildings of Tomsk late in the 19th and early 20th centuries. At the turn of the 19–20th centuries, the wooden construction, is the fundamental planning in the architectural and town-planning structures in Siberian cities. The relevance of the study is determined by the problems of preserving the integrity of historical urban estates in Tomsk, in particular household buildings of which there are currently very few left.

Purpose: A comprehensive analysis of three most interesting estates of Tomsk merchants, namely G.M. Golovanov, A.F. Zelenevskaya, and the Kukhterins and the planning structure and functional zoning of merchant estates, architecture and planning of buildings, and preservation of estate complexes.

Methodology/approach: Historical, archival and bibliographic documents; field research conducted by the authors in 2022; methods of the data identification, comprehensive, systematic and comparative analyses.

Research findings: Collected and analyzed materials on wooden merchant estates in Tomsk. The high urban significance of the historical buildings is determined, the rational zoning and multifunctionality of merchant estates is identified.

Originality/value:  The  comprehensive  analysis  of three  merchant  wooden  estates  of the 19–20th centuries, justification of their value as the main elements of the spatial planning structure of the Tomsk city.

Purpose: The aim of this work is to consider the principles of town-planning regulation and building height control in France and identify effective tools for this regulation.

Methodology/approach: The comprehensive approach, which includes the analysis of local urban planning documents and building morphology.

Research findings: Effective tools of town-planning regulation and building height control are identified. The environmental town-planning regulation is the rule of dimensions and flexible regulation is the rule of the height control. Their introduction is proposed.

Practical implications: The results of this work can be implemented in  practice in Russia.

Originality/value: Examples of regulatory provisions and excerpts from other papers concerning regulations presented in this work, are published for the first time.

In the modern world, increased attention is paid to the sustainable development of urban areas. The sustainability concept embedded in urban planning and architecture leads to the emergence of some other approaches and ideologies. While they may have different emphases, they generally agree with principles and goals of sustainable urban development. Since the end of the last century, the application of this concept in the city has influenced the city and its structure. Lonely this change must come to an omission of the quality of life and people’s relation to the environment.

Purpose: The aim of this work is to examine the influence of application of the sustainable development concept to the city development; consider and analyze this concept. The main attention is paid to problems and solutions of this concept in the urban structure.

Methodology/approach: Consideration of the sustainable development concept and its application in the city; the city analysis before and after the use of this concept; discussion of advantages and disadvantages of this concept.

Research findings: Each city has its own system of coherent urban thinking, a solution to achieve the goal of sustainable development, and a certain approach to a structural solution.

The authenticity preservation of buildings in the historical center of the city and its panoramic perception, are impossible without regulating the number of storeys of new buildings that appear during the reconstruction, renovation and development of green areas.

Purpose: Methodology development of historical and architectural environment of the large city center to identify the critical altitude of historical buildings.

Methodology: the landscape visual analysis, based on theoretical and practical experience in the critical altitude principle.

Research findings: The proposed methodology was tested in 20212022 in the historical center of the city of Penza. It is highly appreciated by the professional community. This methodology includes research of Russian and foreign scientists and practical  approaches. High quality of results are obtained.

Practical implications: The proposed methodology is quite universal and can be used in various historical cities, small towns, and also in largest cities. It can be used both as a whole and in separate stages, depending on the urban planning tasks.

Purpose: The aim of this work is to identify the possibility of mass winter sports, architecture of winter sports complexes. It should be noted that not only the quantity, but also the quality of these complexes is important.

Methodology: Description of the architecture and planning of indoor winter sports complexes. The introduction of such complexes in Russia are considered. Based on statistical data, the most popular winter sports are identified, for which the appearance of complexes is more significant. The general plan and main functional units of complexes are identified.

Practical implications: The quality development and improvement of sports, allowing athletes to train in any season. This will give rise to the architecture of these structures.

Originality/value: The impossibility of holding classes in winter sports all year round, development of the architecture of winter sports complexes, determination of promising options for the development of such complexes.

The article describes spatial planning solutions of educational institutions in Ekaterinodar, built in the middle of the 19th century until the revolution in 1917. Historical, social, humanitarian and other factors that improve architectural solutions of these buildings are identified. Conclusions are drawn about architectural and planning solutions and modernization of original educational institutions, including those survived to present days and the historical buildings of Krasnodar.

Purpose: The aim of this work is to study different interpretations of the term transformation in architecture and define the term transformable architecture.

Methodology: The thesaurus method and comparative analysis. Data comparison allows to define and structure the conceptual apparatus. Works of A.A. Gaiduchenya, N.A. Saprykina, R. Kronenberg, J.D. Lee, R. Reuter are studied and analyzed. These researchers define the transformable architecture and created their own systems of definition of changeable architecture.

Research findings: Analysis concerning the interpretation of the term transformation in architecture show four possible notions. It is concerned if architecture is the intangible system of knowledge or artificial object of material world, and transformation is considered as the process of changing via evolutional processes or the ability to change. Structure of notions helps to define original term of transformable architecture.

Practical implications: This work highlights the concept uncertainty of variable architecture and complex search for materials in the field.

Originality: The term transformation is ambiguous in architectural science. This word is used starting from the evolutional change in architecture and ending by specific techniques of controllable change of space embedded in its architecture at the design stage. The versatility of the term transformation and words with similar roots, creates many interpretations by different researchers.

The convenient living environment has to be currently improved be means of ergonomic recommendations for further redevelopment of buildings in conditions associated with their moral and physical deterioration in the 20th century. The ergonometric analysis is based a widespread model of residential buildings built in the 1950-80s throughout  the country.

Purpose: The analysis of planning structures of standard buildings according to the transit movement in the apartment, zoning and mutual arrangement of ergonomic premises.

Methodology/approach: Terminological and theoretical comparative analyses and modeling; calculation of the coefficient of non-straightness in the planning structure of such buildings; evaluation of convenience of planning structures according to the transit movement, zoning and mutual arrangement of premises.

Research findings: The econometric analysis of two types of movement in the apartment. Functional and planning zoning and relative location of premises are selected and schematically shown. Coefficients of non-straightness are calculated. Evaluation of convenience according to the transit movement, zoning and mutual arrangement of premises.

Originality: The ergonometric analysis of standard residential buildings conducted for the shortest distances and premise location relative to each other.

The article discusses the university infrastructure in large Siberian cities. University campuses are classified depending on their spatial organization and location in the city.

Criteria are used for the evaluation of urban planning of university campuses, that determine the location of universities. Depending on a distance between campuses and academic buildings, university campuses are distinguished between low, medium and high degrees of distribution. University campuses are divided into universities locating at the center, center boundary and periphery of the city.

Based on the proposed classification and town-planning analysis of academic buildings and campuses, the types of spatial structures of university campuses are determined for such large cities of the Siberian Federal District as Tomsk, Novosibirsk, Krasnoyarsk, Omsk, Barnaul, Kemerovo, Irkutsk.

According to the town-planning analysis, the high distribution of universities is mostly often found in Krasnoyarsk and Kemerovo. Universities with low and medium distribution are typical for Barnaul, Irkutsk, and Tomsk.

Operating areas are currently widely used in public service. They refer to rooms with a mass presence of people. The quality of customer service is influenced by a large number of people talking to each other at the same time. As a result, the audibility and intelligibility of speech in the operator-client pair decreases. Partitions of an incomplete height are arranged to improve the quality of customer service in operating areas.

Purpose: Methodology is proposed to evaluate acoustic changes in rooms with a mass presence of people from the standpoint of ensuring speech intelligibility.

Methodology: The method for assessing the speech intelligibility between the operator and client in space with partitions of incomplete height.

Research findings: The proposed method can be used to evaluate acoustic changes rooms from the standpoint of the speech intelligibility. The example is given to the technique used to solve this problem.

Practical implications: The proposed method and developed computer program for its implementation will provide a necessary acoustic mode through a purposeful design of space-planning solutions for partitions and determine their sound-absorbing and sound-insulating characteristics.

Purpose: Finite element modeling (FEM) of the stress-strain state of the five-storey frame building with girderless floors and the basement caused by progressive collapse.

Methodology: FEM is performed in the MicroFe software with the removal of the medium column  in  the  basement  using  the  limit  equilibrium  theory.  Development  of  the  three-dimensional model on a rigid base.

Research findings: It is shown that progressive collapse of girderless floors is impossible after the removal of the medium column in the basement of the experimental building.

The paper focuses on the reliability specification of trouble-free operation crack opening in flexural reinforced concrete structures. The opening width is considered based on the reinforcement safety, i.e., safety due to corrosion.

The probabilistic approach is used in this paper. Instead of traditional economic indicators, abstract values were used, i.e., measures of safety and corrosion damage of reinforcement. Both values range from 0 to 1. Basic formulas, calculation sequence and results are given herein. The probability of trouble-free operation is calculated under the assumption that all initial design parameters and external influences are distributed according to the normal law. Calculations are performed depending on the crack opening duration and maximum permissible values of crack opening width. The obtained values of the reliability specification of trouble-free operation depend on the maximum permissible values of the standard crack opening width. They not depend on the crack opening duration. Calculation results can be used in the probabilistic approach to reinforced concrete structures.

The paper presents research results of the β-SiAlON production from aluminum, silicon and urea nitrides using high-enthalpy thermal plasma flow. Physicochemical properties of β-SiAlON are studied by using the X-ray phase analysis, scanning electron microscopy, and differential  thermal  analysis.  It  is  shown  that  at  the  spicified  plasma  jet  parameters, a thermochemical reaction occurs with the formation of β-Si₅AlON₇. Three zones of the structure formation caused by the temperature gradient in the bulk material as a result of the plasma exposure, are identified and studied. The first zone is directly irradiated by the plasma. The second is the transition zone, which locates between the first and third zones. The third is the thermal heating zone provided by the heat transfer from the irradiated zone.

To date, new synthesis methods of forsterite (Mg2SiO4) ceramics are being searched for refractory industry. The limiting factor of Mg2SiO4  synthesis is its high melting point of 1890 °C, which makes it difficult to conduct experimental studies.

The paper proposes a new method of forsterite synthesis based on thermal plasma. The plasma source is an effective medium for heating and melting refractory materials. For the Mg₂SiO₄ synthesis, such initial materials are used as natural and sub-standard raw materials (silica sand sifting, microsilica, magnesite). The degree of crystallinity varies from 10 to 98 %, which allows studying the formation of the phase composition at different parameters.

According to powder X-ray diffraction patterns, at a MgO/SiO₂ stoichiometric ratio of 1.34, the obtained melting products consist up to 90 % Mg₂SiO₄ and the X-ray amorphous phase content varies from 5 to 12 %. After isothermal exposure, the amorphous phase is represented by silicon dioxide in the polymorphic modification of cristobalite. According to scanning electron microscopy observations, the formation of hexagonal close-packed crystals occurs on the surface of the ceramic sample, with the size ranging from 180 to 250 µm. The elemental composition of the crystal consists of ~ 38.60 wt. % O, ~ 28.54 wt. % Mg, ~ 26.92 wt. % Si, which matches the theoretical composition of Mg₂SiO₄. A detailed analysis of a single crystal shows that the surface structure consists of acicular microcrystals arranged symmetrically, but at the same time overlapping each other, thereby forming a lattice structure. The growth angle between the cubic microcrystals tends to ~87–94 degrees.