Purpose: Identification of possible settlement formation along the Angara River in the Irkutsk agglomeration at different formation stages and its urban development.

Design/methodology/approach: A number of outlined important tasks include the description of each formation stage of settlement with respect to natural resources, urban planning, transport and socio-economic potential; identification of problems and key points of the spatial development of the existing settlement system; solutions of the identified problems. Urban-ecological principles developed by A.G. Bolshakov are used together with the literature in the field.

Research findings: The considered existing planning system includes transport, economic and landscape-ecological facilities.

Practical implications: The paper suggests possible ways to solve the identified problems.

Originality/value: The mentioned facilities can serve as a basis for the settlement formation and spatial development.

Purpose: The aim of this work is to discusses the main periods of the cultural landscape formation in the historical Siberian city.

Design/methodology/approach: This research is required to preserve the cultural landscape in the historical city during its construction and reconstruction. The paper presents the data analysis and refinement obtained during the literature review in the field of architecture and urban planning in Siberia. Applied are the full-scale survey methods, functional and graph-analytic analyses.

Research findings: The data obtained allow identifying the main periods of the cultural landscape formation and development in the historical Siberian city interacting with natural landscape elements. The main theses are formulated for the preservation of the cultural landscape in the historical Siberian city.

Purpose: The development of the main aspects of coordinating various types of urban transport taking into account current trends in the formation the transport infrastructure.

Methodology/approach: Stop-watch reading, visual examination of the road and pedestrian traffic.

Research findings: Identified were placed that require reducing the time of transfer in transport, improving its convenience and increasing the traffic potential.

Practical implications: The proposed methodology to assess the interaction between different types of urban transport implies a rational traffic distribution.

Value: The paper determines the need to improve regulatory, methodological and organizational framework in the transport system coordination at various stages of territory and transport planning in urban areas. 

Purpose: The aim of the work is to identify the similarity and difference between three layouts created by the same technical specifications in order to study the design parameters, which may be inaccessible to the designer without the syntactic analysis.

Methodology/approach: Different approaches are considered in relation to space as an integral structure. Entropy and integration are used for the syntactic analysis, and j-graph is used for the stepwise depth analysis. Investigated are different works, and the precise mathematical tools for the analysis of the planning structure are chosen. The paper proposes the criteria evaluation of the effectiveness of each planning structure. A graph-analytic model is created.

Research findings: The method of parsing is explained in detail, with the selection of tools and spatial values that are appropriate for the objects in question. Criteria and conditions for evaluating the planning structure effectiveness are described. A further vector of work is outlined and the potential of syntactic analysis as a method of pre-project evaluation of work is shown.

Originality: The paper proposes the criteria evaluation of the planning structure effectiveness. A graph-analytic model is created. 

The article explores the negative impact of the grown cultural deposit on stone monuments of Tomsk and ways of its elimination. The urgency is caused by the continuous and complex influence of the grow cultural deposit on historical buildings.

Purpose: The article considers changes in urban development and conditions and new threats of monument preservation and their impact; gives recommendations for the conservation of Tomsk churches and the improvement of their territories.

Methodology/approach: The literature review, the analysis of general technical state of stone monuments in view of the ground water influence on them and proposals on this influence elimination. Articles, books and conferences of various authors – archaeologists and architects – given in the references.

Research findings: Recommendations are given to eliminate the negative impact of the increased cultural deposit, including the territory planning, replacement of coatings, installation of dewatering electro-osmotic devices, impervious curtains, hydrophobization of foundations, restoration of waterproofing and backsplash in compliance with specifications. The importance of informing the population about consequences of uncontrolled cultural deposit growth is noted herein.

Originality: The analysis of the technical state of stone churches of Tomsk such as Aleksander Nevsky and Peter and Paul; recommendations for eliminating the negative impact of the increased cultural deposit growth.

Purpose: Identification of the correlation between service facilities, research and production zone of Russian science cities.

Research findings: Based on the difference in the urban development, calculations include individual objects, taking into account the number of floors, rather than functional zones. The cities of Protvino, Pushchino, Chernogolovka, Fryazino, Troitsk and Koltsovo are analyzed; the population can be compared with the estimated number of new scientific towns. Despite a significant difference in the size of urban areas and the development of the research and production base, these science cities have a close ratio of housing, service facilities and research and production areas, i.e., 60, 10 and 30 %, respectively. The basic layout of science campuses does not change, while economic, demographic and scientific development is observed.

Practical implication: The detected correlation can be called rational and used at the initial stage of planning a new science city.

Purpose: To find classical wooden buildings of the 19th and early 20th centuries in Tyumen.

Methodology: Architectural and typological analyses of wooden buildings of the 19th and early 20th centuries.

Research findings: The materials are developed concerning the current state of the classical wooden buildings in Tyumen, including historical and modern photographs and description of such buildings.

Practical implication: The obtained results can be used to prepare lectures, reports and communications on the history of architecture in Siberia.

Value: The full-scale studies of classical buildings underlie further research of wooden objects of classicism.

The paper investigates free vibrations of rectangular metal plates. The finite element method and analytical calculation are particularly used to determine the vibration frequency. The analytical calculation is based on the equation of motion of a thin rectangular plate. The asymptotic method is applied to determine the dynamic edge effect. As a result, the free vibration frequency is determined for the rectangular metal plate. The finite element analysis is performed in Lira and SolidWorks software packages. For this, a solid plate model with sensors is created to measure the free vibration frequency; the effective mass participation factor was determined.

The plate vibration tests were conducted to confirm the results of analytical calculations. The method of smooth sinusoidal vibrations is used. Spectrum graphs of the plate vibrations are suggested based on the vibration acceleration of sensors. Errors are identified in the free vibration frequencies depending on the applied method. The paper does not consider frequencies with the low effective mass participation factor.

Purpose: Determination of oscillation process mechanisms affecting the coating operation and rational visualization of the results obtained.

Methodology: The analysis of dynamic effects on cylindrical mesh coatings. The considered rational grid shape has a diagonal element in the middle. Numerical calculations are conducted using software.

Research findings: Structures under static loads are studied. Mathematical dependencies are identified and the model of the dynamic load is proposed. Direct integration of equations of motion is carried out. Acceptable ratios are obtained for geometric parameters.

Practical implication: Extreme values of force factors and parameters are recorded for the structure deformation at given time interval.

Originality/value: Oscillatory processes of operating devices and mechanical failure of the attached equipment considered in using cylindrical mesh coatings in specific conditions.

Purpose: Reinforcement analysis of concrete roof frames of one-storey industrial frame building with respect to the detected corrosion of reinforcement and longitudinal cracks with the opening width of several millimeters in the concrete protective layer.

Methodology: The analysis is performed by using the finite element modeling in the MicroFe software, the developed model of detected damages of the concrete structures, and design solution of the roof frame strengthening.

Research findings: Rationale is given to the lower roof frame strengthening with polymer fiber using two analytical models, namely steel reinforced element and layer material element. The obtained results are then compared.

The use of steel-reinforced (composite) floor structures with partially concreted steel beams and prefabricated flooring elements is an effective solution in terms of reducing the material consumption and increasing the structural rigidity. The experimental results of partially concreted composite beams and beams as part of full-size ceilings are studied and analyzed herein. It is shown that the stiffness graph of simple steel-reinforced concrete beams of any shape can be divided into 3 stages: an initial stiffness drop, normal operation, and transition to the limit state with subsequent destruction. The boundaries of these stages are identified for each beam type. The stiffness of the combined cross-section of the partially concreted beam with the rod reinforcement is calculated using well-known formulas from regulatory documents. The element rigidity without rod reinforcement is determined with the decreasing coefficient. Tests of full-size ceilings with partially concreted beams and prefabricated floors confirm the possibility of using standard formulas for the stiffness calculation. However, the width of the compressed concrete flange should be taken into account by less than 3 times than for monolithic slab. The destruction of bending composite structure is accompanied by plastic deformation in flanges of I-beam, destruction of compressed concrete and steel–concrete interaction. However, it does not lead to zeroing of its rigidity. When residual stiffness reaches the ultimate strength state, it is at least 60–70 % of its normative value. This rigidity can be used for the progressive collapse analysis of buildings.

Groundwater lowering is a method of stabilizing landslide slopes. To date, the effect of water reduction on the technical condition of buildings has not been sufficiently studied. This may negatively affect the technical condition of buildings due to the development of additional deformation of foundations and foundation soils.

Purpose: The aim of this work is to assess the impact of cased hole with filters on the technical condition of buildings in the area of groundwater lowering.

Methodology/approach: Long-term field observations of the groundwater level at the water supply site; monitoring of the technical condition of buildings; analysis and generalization of the data obtained.

Research findings: Based on annual monitoring of the building height, monitoring of changes in the building state and the engineering and geological analysis are performed in the period from 1987 to 2020. It is found that groundwater lowering leads to building deformation and a decrease in its technical condition due to nonuniform soil compaction in this area.

Research implication: Groundwater lowering near buildings can significantly affect their technical condition due to the soil compaction even at a considerable distance from the waterlowering devices. In developing groundwater lowering projects, special attention should be paid to heterogeneity of the ground layer on the building site and its impact on the formation of relative deformation of buildings.

In modern construction, more and more attention is paid to the roadbed quality. At the same time, in most regions of the Russian Federation there is a shortage of natural building materials of the required quality. In this regard, methods of stabilizing natural clay soils should be developed to satisfy the regulatory documentation.

Purpose: The chemical additive effect on mechanical properties of clay soil.

Methodology: The proposed method of concentrated effect of drying agents (lime, active fly ash) can potentially improve the mechanical performance of clay soils, i.e., strengthen the soil. Compressive strength testing of clay soil (light powdery loam) includes its treatment in hydrated lime in the amount of 2, 4 and 6 wt.%, hydrated high-calcium fly ash in the amount of 4, 8 and 12 wt.%, and a combination of slaked lime and chemical additives-accelerators (CaCl2, FeSO4, NaOH) in the amount of 0.5 and 1.0 % of the dry soil mass.

Research findings: Even small amounts of lime improve the clay soil strength, which exceeds the effect from the fly ash introduction by 194 %. CaCl2 and NaOH additives significantly accelerate the strength gain. The introduction of FeSO4 improves the strength gain kinetics at the first stage (up to 7 days) and further causes a complete destruction of the material structure. The compaction also shows a significant decrease in the tensile strength during the time between the dry agent introduction and compaction.

During operation, pipeline hydraulic characteristics change due to the presence of sedimentary layers in pipes. The efficiency coefficient in an important parameter for the evaluation of the pipeline operation.

Purpose: The aim of this work is to prove the necessity of using the efficiency coefficient in the hydraulic analysis of water supply and removal with internal sedimentary layers in pipes in order to predict their hydraulic characteristics with any (measured) thickness of the sedimentary layer.

Methodology: Dependences used herein are repeatedly published by the authors.

Research findings: Calculation tables are developed to design the reference manual "Calculation tables for hydraulic analysis of water removal in pipes with sedimentary layers".

Practical implication: The proposed values of the efficiency coefficient of water supply and removal can be used in hydraulic calculations to predict the hydraulic potential of pipes with sedimentary layers.

The relevance of research and application of glass-ceramic materials based on spinel (MgAl2O4) is due to its unique properties such as strength, heat resistance, and high thermal conductivity. These properties make spinel a popular material for creating hi-tech products and coatings.

The paper presents the experimental results of the production spinel-based glass ceramics with the silicon dioxide content 10 to 50 wt.%. Thermal plasma melting is used obtain glassceramic samples, at 10 kW power and 90 s melting time. The obtained samples are studied by XRF, EDX, IRFS, SEM methods.

It is shown that the introduction of SiO2 in the amount of not over 20 wt.% into the mixture with stoichiometric spinel, phase transformations with the formation of binary 2MgO·SiO2, MgO·SiO2, 3Al2O3·2SiO2 compounds do not occur. With increasing SiO2 content from 30 to 50 wt.%, the effect from SiO2 is significant, a quasi-amorphous phase appears in the material matrix. At the same time, the SiO2 content of 30 wt.% provides weak intensity of the stoichiometric crystalline phase MgAl2O4 at 2θ = 36.6, 44.7, 59.3, 65.4 degrees. Samples with the SiO2 content 40 to 50 wt.% are X-ray amorphous. In this case, the diffusion halo narrows due to the dominance of Si4+ during the lattice formation. This phenomenon is also confirmed by IRFS results.

Based on SEM observations, a complete dissolution of the MgAl2O4 crystalline phase occurs. When the content of SiO2 is 30 to 40 wt.%, dissolution of the spinel crystalline phase is accompanied by the formation of local regions rich in Mg and Al, i.e., differentiation proceeds in the condensed phase.

The research results will be of interest for the development of heat-shielding materials, and can be used for the catalyst development, in electronics and other industries producing hi-tech ceramics.

Purpose: Identification of deformation presence or absence, fiber destruction in manufacturing asphalt concrete mixes contain ning polymer fiber.

Methodology: Initial dispersed reinforcing fiber made of thermoplastic fiber-forming polymer and mineral thread, fiber extracted from asphalt concrete, and fiber exposed to weather conditions are investigated using a weatherometer IP-1-3. Аn MIM-10 metallographic microscope is used for the metallographic analysis. The infrared spectrophotometer SPECORD M-80 is used for the material identification. Physicochemical tests of fiber are carried out in a certified laboratory "Khimvolokno".

Research findings: Dispersed reinforcing fiber made of thermoplastic fiber-forming polymers show deformation in compacting the asphalt-concrete mix at impact points of mineral material grains. At the same time, mineral fiber used as a dispersed reinforcement is not subjected to such deformation. The fiber properties are not affected by natural and climatic factors. It is found that natural and climatic factors do not cause the fiber destruction in dispersed reinforcement. The properties of reinforcing fiber slightly change, which allows them to perform a reinforcing function throughout the established service life of asphalt concrete pavements. Indentation of mineral material grains into fiber made of thermoplastic polymers leads to fiber jamming by grains, that prevents them from being pulled out, that, in turn, increases strength and rheological properties of asphalt concrete.

Value: The analysis of chemical fiber characteristics is requireв to satisfy the growing interest in dispersed reinforcement of asphalt concrete. The quality of polymer fiber used for reinforcement can be changed under the influence of external factors and affect the quality of road pavements.

The problem of road pavement deterioration due to the forces of frost heave on operating roads remains highly relevant for many regions of Russia.

One of the effective methods for regulating the magnitude of frost heave in the roadbed of highways under unfavorable soil-climatic conditions is the installation of a capillary barrier. This method, using injection methods for soil transformation, has been previously justified by the authors based on field and laboratory research.

However, for practical implementation of the proposed method, the key unresolved research tasks are the determination of the calculated depth of the capillary barrier within the roadbed and its optimal thickness.

In this regard, the aim of the research is to provide a calculated justification for the boundaries of the capillary barrier made from injected solution to prevent frost heave in the roadbed.

The methodological basis of the study includes theoretical research methods such as abstraction, analysis, and synthesis.

The article formulates the condition for transitioning from an "open" freezing system to a "closed" system and proposes criteria for creating a capillary barrier. A solution is obtained to determine the maximum thickness of the capillary barrier, which depends on the properties of its material and the coefficient of moisture conductivity. The solution to the problem of locating the capillary barrier within the structure of the operating roadbed is presented, based on correlating the zone of intensive moisture transfer with the isotherms of temperatures in the freezing massif.