The article discusses the main trends in the formation of art objects in the urban environment. Special attention is paid to the development of aestheticizing the urban environment.

   Art objects are studied in the urban context.

   The article analyzes the concepts of creating art objects in the urban space. Variants of art objects are proposed in accordance with the creation of a comfortable urban environment. The article substantiates the idea about art objects in the urban environment as elements of the urban space identification.

  The aim of the work is to analyze the "Smart City" model, including reasons of its development; the concept development; the transition of the "Smart City" model to the Smart City Project in Russia; identify the Project content.

   Methodology: The urban planning model "Smart City" is one of the ways to improve the efficiency of territory management in large cities. Research is based on the collection and analysis of the appropriate normative, theoretical and practical documents.

   Research findings: In practice and within the framework of Russian legal regulation, this model is determined by the Smart City Project of the Ministry of Construction of the Russian Federation. The Project concepts of digitalization do not fully meet the need for the development of a large city. On the one hand, the project concerns the sphere of advertising high-tech goods and services, and on the other, it is a new urban development model. The problem lies in the duality of the definition of the smart city concept and urban planning technologies. Practical implications: The proposed definition of the Smart City Project is a set of ideas and approaches allowing to generate a strategy of urban development based on the parameters of the urban environment, including the prediction of changes in these parameters. In this case, the Project considers the largest number of quality parameters of the urban environment, using the economy analysis, sociological and other data. Strictly technical re-equipment of urban infrastructure is included in the Project.

   In this paper, the climatic conditions are considered for the Efremovsky district and the city of Efremov, in particular to identify the mutual effect from the landscaping system and residential development area. The construction-climatic passport is prepared for the city of Efremov in the Tula region. As a result, insolution of urban development and location of functional zones of the city are identified.

   The design concept of the Trondheim School of Architecture is modernization of architectural education in Europe in the 21st century. Education must include the understanding of principles of sustainable development, social context, place for design of buildings, transformation of the professional architectural mentality to make creative methods a part of continuous and harmonic, spiritual cultural process. The learning environment must provide knowledge and skills and a stimulus for personal development. The rapid change in the living environment in the 21st century has presented new challenges future architects. These problems most of all affect the design concepts of new architectural schools, including the Trondheim School of Architecture.

   The purpose of this work is to develop a methodology for the renovation of open urban space in the development area of the city of Novosibirsk using Depth Map software, which allows for the pedestrian traffic analysis.

   Methodology/approach: The analysis of Russian and foreign data, 2) study of software for conducting required research, 3) the
analysis of field research data, 4) urban planning and configurational analyses.

   Research findings: Russian studies do not offer such a configurational approach. Most of the studies that consider pedestrian space, represent pedestrian traffic from point A to point B, while in other studies the movement is a more complex symbiosis of social activities not only without goal-setting, but also without specific choice.

   Practical implications: A hypothesis is suggested for future research, which implies the usefulness of the analytical apparatus of spatial theory to determine the metric and topological integrity of locally integral urban formations.

   Originality/value: Classification proposed for open space of typical development areas using data on spatial characteristics obtained by the configurational analysis.

   The paper reviews the long span structure with the ethylene-tetrafluoroethylene (ETFE) coating. The ETFE coating properties and possibilities of its application are considered herein. The paper presents results of natural heat engineering tests of separate cells of the coating in the form of a foil package and enclosing structure segment of natural size with various number of ETFE layers and lighting tests of multilayered coatings. It is shown that high thermal protection and illuminating parameters can be gained for ETFE-coated enclosing structures for the operation in arctic conditions.

   Mechanical strength testing of ethylene-tetrafluoroethylene (ETFE) film is performed on the test machine INSTRON. The average elastic modulus of the film is 35.8 MPa. Under subsequent loading, the elastic-to-plastic stage transition occurs with decreasing elastic modulus to 1.78–2.71 MPa and then to 0.06–0.086 MPa. Strength testing of the ETFE film 250 µm thick at 8.577 kPa uniformly distributed load does not lead to the film rupture either at positive (15–18 °С) or negative temperatures (–23–29 °С). A multiple damage of the film under an 8.50 kPa load at −26 °С does not lead to its disruption. The film bending at positive and negative temperatures reaches 84 and 58.2 mm, respectively. Strength testing of the ETFE film demonstrates its ultra-high strength properties, and thus predicts its wide use in the formation of comfortable conditions in buildings created in Arctic and other territories of Russia.

   In terms of shaping of building structures, numerical calculations are required for the structural unit elements, deformability, limit forces under loads for a successful application of fully-prefabricated building structures of a closed type with glued wood-to-steel plate bolt joints. As a result, theoretical calculations are compared with the experimental data. It is shown that the proposed decisions concerning the structural units are reliable. The yielding parameters of the structural units are corrected in the model of the fully-prefabricated building. The scope of application is determined for the units of multi-connected structures or structures with glued wood-to-steel plate joints.

   The paper presents the strength analysis of bending reinforced concrete elements in the Matlab support package. The versatility of the deformation model is its ability to conduct control tests, for example, verification of structural analysis at the design stage. Based on the standard stress-strain state diagrams of materials and iteration procedures, two independent nonlinear analyses are suggested. One of the main accepted conditions is that iteration procedures occur at the elastic behavior of the member. Iteration procedures determine the maximum member curvature and its deformation. The strength criterion is theoretically calculated deformation, which must not exceed permissible values specified in construction codes and regulations. Calculation algorithms are given in flowcharts. In conclusion, the results of experimental data are presented.

 

   Mullite has low thermal expansion coefficient, thermal conductivity and excellentresistance to thermal shock, and plays therefore an important role in the synthesis of modern ceramic materials. The paper presents the experimental results of mullite ceramics synthesis using thermal plasma. The ceramic samples are obtained from natural raw materials such as boehmite and silica sand in the stoichiometric Al₂O₃/SiO₂ ratio of 1.86, 3 and 5.67. It is shown that the optimal operation mode of the arc plasma torch in the synthesis of mullite-containing samples from an 8 g charge weighing includes 80 A current, 100 V voltage, and 60 s exposure time. With such technological parameters, the melting product is a hemisphere with diameter 23 mm and thickness 11 mm, which indicates to a complete transition of the initial components to the molten state. The synthesized ceramic samples are characterized by the crystalline phase of mullite 3Al₂O₃ ·2SiO₂. At the same time, at the Al₂O₃/SiO₂ ratio of 1.86, cryptocrystalline diffraction maxima are observed at 2θ = 53–54° and 69–76° due to the increased content of SiO 2 . According to morphological studies performed for the Al 2O₃/SiO₂ ratio of 3, which is the traditional stoichiometric ratio for the mullite phase synthesis, the matrix of the synthesized sample is represented by the amorphous phase penetrated by filamentary single crystals of mullite with the average length of 3.3 μm and 0.86 μm thickness. It is found that the transition layer between these phases has a glass-ceramic structure, which is consistent with the results of the X-ray phase analysis.

   Research into the dependence between the clinker activity and its fine structure and mineralogical composition shows that at the constant conditions of clinker baking and cooling in a particular furnace for a certain period of time, the clinker structure can be considered as unchanged. This paper studies the dependence of the clinker activity of Portland cement on its structure based on the data obtained during the study of the main clinker minerals. The study of six polymorphic modifications of alite and the lattices parameter measurement help to obtain X-ray diffraction patterns, which identify polymorphic modifications of alite.

   Creation and maintenance of indoor climate at the lowest costs is one of the main tasks of engineers in the construction industry. It is necessary to take into account not only the thermal characteristics of modern building materials and structures, but also indicators of thermal comfort based on the heat balance of a person. It is necessary to pay attention to heat losses in the of education institution buildings in the absence of unambiguous required data on this matter in the normative documents. Various techniques of definition of heat gain from people are considered, the comparative analysis of techniques is conducted, factors influencing metabolism and heat balance of a person at rest and at work are identified, and the heat gain from students is calculated with respect to their age and physiological characteristics. These calculations can be used to detect the heat balance of education institution buildings. It is shown that theoretical calculations are in good agreement with the experimental data.

 

   Oil refineries and other industrial enterprises generate a large amount of sewage contaminated with petroleum products. Sewage must be treated before it can be discharged into a water body. Sewage treatment methods often do not allow reducing the content of petroleum products to the maximum allowable values. This is because sewage is a microheterogenous system characterized by variable composition and high stability. It is thus important to study factors affecting the high aggregate stability of sewage as well as the development of theoretical foundations for optimizing sewage treatment. The paper presents the study of properties of multicomponent colloidal emulsion systems, factors affecting their high aggregative stability and develops theoretical foundations for optimizing sewage treatment. The systems simulating industrial effluents according to the basic chemical composition obtained by the dispersion method are studied herein. Research also includes the kinetics of precipitation of petroleum products from sewage, sewage treatment parameters during the intensive mixing of the emulsion with air. The express-method determination is used for the petroleum product content in emulsions. The regression analysis is used for the dependence of the optical density on the content of petroleum products. It is found that 10^-6 µm particle removal continues for 20 min, which corresponds to the rapid coagulation. The stability of clean-contamined emulsions decreases by about 10 times with increasing barbotage speed to 30 l/h. The latter being 10 l/h, is sufficient when using Ca(OH)₂

   The aim of this work is the instrument-aided structural survey to recover the operability of a five-storey brick building on a pile foundation after significant deformation.
   Methodology: The MicroFe software is used to simulate the stress-strain state of the building and develop the base–foundation–building system model. Research findings: During both construction and operation of the building, its spatial stiffness is disturbed with the crack formation in brick walls due to insufficient pile installation, i.e., the pebble-gravel layer is not reached owing to difficult engineering and geological conditions. Practical implications: The obtained results are used to develop recommendations to ensure the required spatial stiffness of the building by the outer wall reinforcement with strained steel bars locating at the level of intermediate floors.

   The dynamic properties of bridge girders depend on the design solutions, namely the replacement of the roadway slab by the orthotropic, deviation from standard solutions in the formation of longitudinal schemes, and the use of a new type of supports causing the dissipation of vibration energy and gyropendulum effect.
The control for dynamic properties with regard to multifactorial defects, is characterized by ignoring the shock dampers of vehicles moving on the roadway. In this case, it is advisable to control the dynamic properties with regard to the energy dissipation of oscillatory processes within the internal and external strain boundaries, each of which can be functionally solved by the dependencies between the parameters of static and dynamic conditions of elasticity and plasticity. Long experience in diagnosing bridges under varying conditions of moving load allows identifying critical moments and limiting values of dynamic properties, at which the integrity of the span-vehicle system is violated. The difference in the operation of the system elements is complicated by the influence of a wide range of dynamic impacts, whose nature is opposite to the mechanical impact of vibra-
tion dampers such as all-round moving supports. In this case, the criterion for the dynamic property control are anti-phase vibrations of the girder and supports and their stiffness ratio. Based on the results, the dynamic property control includes the identification of the critical speed of the moving load based on various forms of energy of the deformed state of the structure, including resonance; conditions of the energy dissipation of the vibration process of the span-vehicle system; new parameters and requirements for bridge structures with controlled dynamic properties adequate to those of numerical simulation of bridge girders of 40 to 60 or 80 m and longer; optimization and modernization of bridge vibration-based diagnostics.