Proceedings of EECE 2019

Table of Contents

1. Frontmatter

2. Regularities of Change in the Properties of Paint Coatings on Cement Concretes at Moistening

   Valentina Loganina, Roman Fediuk, Kseniia Usanova, Roman Timokhin

   Abstract

   Despite the fact that the durability of paint coatings on various substrates (e.g., metal) has been studied early, this information for coatings on cement concrete has not been studied enough. The paper presents research data on the regularities of the change in the decorative properties of coatings of cement concretes during exploitation. Five types of paint coatings were used. Ultraviolet irradiation was carried out by a PRK-2 lamp, shine was measured by a FB-2 shine meter, and surface roughness of the coating was determined using a profiler mark TR-100. It is shown that the degree of influence of the relative humidity of air on the change in the shine of coatings on a porous concrete substrate affects more than in coatings on a dense glass substrate. It is found that during the incubation period, there is an insignificant increase and possibly a decrease in defectiveness. In the active stage of accumulation of damages, significant changes occur in the structure and properties of the coating. These outcomes suggest that depending on the surface quality (porosity) and the method of application, optimal rheological characteristics of the paint should be selected to facilitate the production of a surface of coatings of specified quality.

3. Quality of Construction Works at the Design Phase

   Thi My Dung Do, Thanh Quang Khai Lam

   Abstract

   The quality of a construction work is decided mainly in the construction and completion phase of the works. However, in order to serve the best for the construction phase, the design work plays a very important role for all construction works, regardless of the big or small construction size or items. The design work helps the works to be constructed in accordance with technical standards, ensuring safety and environmental sanitation. In addition, the quality of design also plays an important role in determining the effectiveness of investment capital. In the preparation phase of investment, the design quality determines the use of economical, reasonable and economic investment capital. If the quality of design work in this phase is not good, it will lead to waste of capital investment, affecting the following design phases because the following design phases are developed based on the previous design. In the implementation phase of investment, the quality of design work has a great effect on the quality of the works, which is good or not good, safe or unsafe, economical or wasteful, favorable or difficult construction conditions, fast or slow construction progress, etc. In this phase, the design work is considered to be the most important role in the phases of the investment process. In the project exploitation phase, the design quality plays a key role in deciding the exploitation and use of the works whether it is safe, convenient or dangerous, difficult; the quality is good or bad; cost of works is high or low; the construction life ensures the requirements set out in the project. In this article, the authors study the solutions to improve the quality of construction works in the design phase.

4. Analytical Dependence of Deflection of the Lattice Truss on the Number of Panels

   Mikhail Kirsanov, Dmitrijs Serdjuks, Karina Buka-Vaivade

   Abstract

   The case of load in the middle of the span is considered. An algorithm is given for deriving the analytical dependence of the deflection of a truss on the number of panels. It is shown that for a certain combination of panel numbers over the height of the truss and along the length of the span, the determinant of the system of equations of node equilibrium turns to zero that corresponds to the kinematic variability of the structure. It is noted that numerical calculation can obscure this feature due to inaccuracy of calculations. To obtain an exact formula, the computer mathematics system Maple is used. The coefficients of the final formula are obtained from the solution of linear homogeneous recurrent equations found from the analysis of the sequence of solutions for trusses with different number of panels. An example of a scheme of possible velocities of nodes of a variable truss is given. The formula for the deflection of the truss for the number of panels for which the truss is unchanged is derived by induction.

5. Flare Emissions from Asphalt Plants

   Vyacheslav Manokhin, Svetlana Sazonova, Sergey Nikolenko, Alla Zvyagintseva

   Abstract

   Road construction has a negative impact on the environment. In particular, asphalt plants are usually located within the boundaries of settlements. This is due to the need to save transport costs during the construction, repair and maintenance of urban roads. The construction of urban roads, as well as their repair and maintenance, often requires the use of technology for the “hot” preparation of asphalt concrete. But this technology is associated with drying nonmetallic materials: sand, gravel, mineral powder, as well as heating bitumen. Moreover, the process is accompanied by emissions of dust and carbon, including high molecular one, which affects the environment negatively. The work used the results of a numerical and physical experiment. Determination of gas concentration was carried out by chromatography and photo-calorimetry methods; dust content was estimated by the gravimetric method and by external filtration. The dispersed and elemental composition of dust was established by X-ray spectral microanalysis with visualization of samples of captured dust. In this paper, we use an alternative method for calculating the dispersion of flare emissions based on the Reichard theory. Such calculation results agree better with experimental data. The calculation is carried out according to the model developed in the work, taking into account the initial rise of the jet, which is most accurately estimated by the method of M. E. Berlyand. The results of the refined calculation allow us to improve the process of preparing asphalt concrete and make it environmentally friendly.

6. Laboratory Tests of Welded Corrugated Beams with Perforations

   Alexandr Bryantsev, Vladimir Absimetov

   Abstract

   As the Kazakhstani and foreign sources currently propose the only way to reinforce perforations in a corrugated web, development of the new and improvement of the existing methods to reinforce the round perforations appear to be a crucial task. Load-carrying capability of beams with corrugated web that is weakened by perforations requires in-depth consideration of reinforcement of the perforated areas to ensure integrity, stability and longevity of structural steels. The practical application in construction of welded beams with corrugated web weakened by perforations requires relevant laboratory tests using large-scale models. This study is to address several issues: to assess the effect of stiffening of various shapes on hardness and stability of the beams with corrugated web; to investigate deformability of the beam with corrugated web both with and without perforations subject to the linear and nonlinear operations; to study specifics of extreme limit states, as well as models’ behavior under load; to determine the maximum load-carrying capability and limit deflection. The most efficient types of stiffening of the perforations in corrugated web have been determined. A comparative analysis of experimental and computer-assisted beam deflection data is performed. On the whole, the conducted experimental model studies have allowed to find out the key characteristics of load-carrying capability and deformability, to determine specifics of loss of stability of flanges and corrugated webs for different perforation stiffening techniques.

7. Advanced Sol-Silicate Paint

   Valentina Loganina, Yerkebulan Mazhitov, Roman Fediuk, Vatin Nikolai, Roman Timokhin

   Abstract

   Deficiencies of silicate paints are revealed. Novel sol-silicate paint obtained by mixing liquid glass and silica sol has been developed. The nominal viscosity of the paintwork was determined using a VZ-4 viscometer. The relative hardness of the coatings was determined using the M-3 pendulum device. The tensile strength (cohesive strength) was determined on a tensile testing machine IR 5057-50. Analysis of the IR spectra shows that the presence in the composition of the polysilicate binder of various polymer silica provides increased durability of silicate coatings. Dependence of the relative hardness of the films based on the polysilicate solution on their thickness is calculated. The presence of polymer varieties of silica in the polysilicate binder was established, which provides increased durability of silicate coatings. A correlation between the content of high-polymer fractions of silicon-oxygen anions in the polysilicate solution and the tensile strength of the films was revealed, which consists in the fact that with an increase in the content of SiO₂, an increase in the tensile strength of the films is observed. Thus, in accordance with its exploitation characteristics, the developed sol-silicate paint can be used for decoration of both external and internal walls of buildings.

8. Compressed-Bent Reinforced Wooden Elements with Long-Term Load

   Svetlana Roshchina, Mikhail Lukin, Mikhail Lisyatnikov

   Abstract

   A complex stress–strain state (compression with blending) usually occurs in parts of spacer building structures (arches, frames), with out-of-site loading of rod systems (upper truss belts), columns, etc. Studying of reinforces wooden structures and research of stress–strain state under short-term and long-term loads required developing calculation methods for such constructs and taking into account properties as stress–strain structures’ state, heterogeneity of materials in complex structure, work compatibility, creep of wood and glue, etc. Assumption of perfect material elasticity is often applied when calculating building structures. The idea of perfect material elasticity (the basis of classical theory of elasticity and structural mechanics) for many materials is sufficiently confirmed by experiments with short-term loading at low-stress level. At the same time, with long-term load even at relatively low level of stress, some materials including wood reveal deformability at constant stress, i.e., they have creep. In this regard, accounting for creep in reinforced wooden elements is an integral part of structural calculations for beautiful states.

9. Separation of Relative Deformations of Buildings from a General Displacement Vector of Deformation Marks

   Olga Tsareva, Nikolai Pshchelko, Vladimir Glazunov, Anatoliy Yugov

   Abstract

   The article presents a technique for distinguishing relative deformations of buildings from the general displacement vector of deformation marks in the presence of reference points. Displacement vectors are obtained from a linear spatial notch solution. In particular, knowing the distances between the reference points and the deformation marks, we obtain the coordinates of the marks located on the building in the initial and the current observation cycles. Knowing the coordinates of the marks, we calculate the vector of displacement marks for a certain period of time. Next, they carry out the separation of the vectors of the displacement of the marks into components and determine the type of deformation. Absolute deformations are determined from the support points. In this case, the distance between any pair of deformation marks of the object does not change during the deformation, but in the general case, the distances from the points of the object to the reference points change. In case of relative deformations, the distances between the deformation marks change. This fact is used to separate absolute and relative deformations. The results can be used in assessing absolute and relative deformations, in particular, buildings of cultural heritage monuments.

10. Soil-Concrete Foundation with Lime-Containing Waste as a Reinforcing Component

    Andrei Gavrilenko, Igor Gandelsman, Lubov Zakrevskaya, Petr Lubin

    Abstract

    This article discusses the theoretical aspects of the structure formation of strengthened cohesive soils. This article contains the analysis of the most promising methods for the chemical strengthening of soils by mining waste. This article demonstrates information on the selection of the composition of a complex binder, based on lime and clay soil. The research is relevant because building industry needs territories suitable for building. The research describes methods of mineralogical and chemical analysis, X-ray diffraction, electron microscopic examination and flow table test. During the research, the authors could determine the optimal soil-concrete composition which is: clay soil—57–68% of the mass and lime waste—20–30% of the mass. The optimal soil-concrete composition has strength 4.07 MPa, bending strength 0.56 MPa, water resistance coefficient 0.78 and frost resistance grade F25. This article shows new technology of strengthening clay soils with lime, simplified in comparison with the method of mechanical activation. The study also confirms the possibility of using these compounds in 3D technology in construction.

11. Parametric CFD Analysis of Hydraulic Transient in a Pipe with Air Damper

    Svyatoslav Khorobrov, Vitaliy Sergeev, Vladimir Kalaev

    Abstract

    Hydraulic transient is the physical phenomena which influence is always underestimated. In this paper, hydraulic transient is described as an oscillation system consisting of tube with liquid and damper with gas. 2D CFD method under the assumption of absolutely rigid walls employed to obtain the solution. Tait equation of state for weakly compressible liquid and ideal gas model for compressible gas used to describe the behavior of liquid and gas, respectively. VOF model employed to resolve multiphase flow. Firstly, the importance of damper presence with gas inside studied. Both general analysis and Fourier analysis for the oscillating process were taken. The parametric study of damper geometry performed using two input parameters. Dimensionless output parameters introduced to describe the difference both between the presence and the absence of damper and between different input parameter values.

12. Fire Resistance of Loaded I-Section Column from Light Gauge Steel Thin-Walled Profiles

    Marina Gravit, Ivan Dmitriev

    Abstract

    This chapter presents the fire resistance calculation of the loaded I-section thin-walled steel column 380 × 260 mm and consists of 2× C-shaped profiles 380 × 125 × 30 × 3.5 without fire protection. There were considered some theoretical dependences of the fire resistance determination according to Russian and European standards, temperature gradient modeling in SOFiSTiK PC, and a comparison with the results of experimental tests. Modeling a section with an air buffer showed good convergence with the results according to the European standard, and without it, to the Russian one. This is due to the presence in the calculation of the correction factor of the shadow effect k_sh. Ignoring the shadow effect leads to conservative solutions similar to the Russian standard. Theoretical dependencies according to regulatory documents showed a large deviation from the actual results of fire tests. Critical temperatures of 594.09 °C (Russian standard) and 547.27 °C (European standard) differ by more than 20% from the experimental values −451.3 °C. The obtained approximation of experimental data in the form of a mathematical temperature dependence on time will make it possible to predict an increase in temperature in thin-walled profiles of other geometric sizes and configurations.

13. The Impact of Aggregates Type to Abrasion Resistance of Mortar

    Andrey Makaronichev, Svetlana Belyaeva, Leonids Pakrastins

    Abstract

    Abrasion resistance is one of the most important durability properties of concrete. Especially, highway, airport and industrial floor pavements should be resistant to abrasion. The investigation is directed to define the suitable aggregate of mortar to be used in a pulpline like a lining protective layer against an aggressive abrasive environment of water with coarse small particles of rocks. The paper examines the influence of aggregate type on abrasion resistance of mortar. Four different aggregate types (corundum, gabbro, quartz, basalt) were used to produce mortar. All samples have similar structure and therefore have constant grading, consistency of mortar, volume ratio between aggregate and cement, but different water–cement ratio. The results of test were showed that increasing wearing properties of aggregate impacts to increasing wearing properties of mortar. The mortar with corundum has the best properties to wear, so it is more suitable in mortar for abrasive environment.

14. Influence of Temperature on Durability of Concrete Exposed to Liquid Corrosion

    Sergey Fedosov, Varvara Roumyantseva, Viktoriya Konovalova, Aleksey Osyko

    Abstract

    The most soluble component of Portland cement-based cement stone is calcium hydroxide. The intensity of liquid corrosion of concrete is determined by the rate of leaching of cement stone, that is, the rate of removal of calcium hydroxide from the concrete body. When the temperature decreases, the solubility of calcium hydroxide increases, and therefore, the rate of corrosion processes that occurring in concrete under the influence of liquid media increases. Reducing the water absorption of concrete allows to control the intensity of mass transfer processes occurring during corrosion in concrete and affects the durability of concrete and reinforced concrete products. The results of the study of the kinetics of cement concrete leaching showed that in the samples with hydrophobic additives state close to equilibrium in liquid corrosion is achieved earlier. This is due to the fact that the content of “free calcium hydroxide” in hydrophobized samples is less, while the possibility of developing corrosion of concrete is reduced. The data obtained as a result of the experiment make it possible to determine the concentration value for the portable component “free calcium hydroxide” over the entire thickness of the concrete structure at any time and with the help of a mathematical model of concrete corrosion of the first type to calculate the mass transfer parameters and establish the service life of the concrete product. The introduction of hydrophobic additives in the composition of cement concrete and temperature control during operation of the concrete product allows providing the required durability and reliability of structures made of concrete.

15. Restoration of Destructive Wood in Supporting Zones of Wooden Beams

    Aleksey Gribanov, Tatyana Glebova, Svetlana Roschina

    Abstract

    High requirements for preserving architectural appearance of building elements and structures of historical and cultural value impose serious restrictions on restoring bearing capacity methods of acting constructs and preventing their failure, thus, updating new researches in this area. Most common defects for structural elements are biological damage to supporting zones of coating and floor beam structures. Use of polymer composition impregnation in destructive beam zones allows restoring physicomechanical properties of wood and preserving architectural structure appearance as whole. The aim of the study is to assess the possibility of restoring destructive wood by impregnating polymer compositions filled with carbon materials. To achieve this goal, the tasks of determining the strength of the restored wood to collapse and chipping along the fibers and comparing the results with indicators for healthy wood have been solved. The paper presents technique for impregnating a polymer composition to restore bearing capacity of supporting wood zones influenced by destruction. This work presents results of X-ray tomography of reconstructed samples with wood destruction; technique of testing samples for crushing and shearing along the fibers; dependences of “stress strain”. An increase in strength of reconstructed wooden specimens during crushing along the fibers was found to be 77%, compared with samples from destructive wood, and 83% when chipping. The conclusion presents main test results, comparison between previous works and determines the scope of presented method.

16. Dynamic Stability of Orthotropic Rectangular Plates with Concentrated Masses

    Rustamkhan Abdikarimov, Dadakhan Khodzhaev, Bakhadir Mirzaev

    Abstract

    A mathematical model of the problem of dynamic stability of viscoelastic rectangular orthotropic plates with concentrated masses is presented in the paper on the basis of the Kirchhoff–Love hypothesis in a geometrically nonlinear statement. The mathematical model of the problem is constructed with account for the elastic wave propagation. The effect of the action of concentrated masses is introduced into the equation of motion of the rectangular plate using the Dirac delta function. Using the Bubnov–Galerkin method, based on a polynomial approximation of deflection and displacements, the problem is reduced to the system of nonlinear integro-differential equations with variable coefficients. The solution of the resulting system is determined by the suggested numerical method. The Koltunov–Rzhanitsyn kernel with three different rheological parameters is chosen as a weakly singular kernel. Over a wide range of changes in mechanical and geometric parameters of hereditarily deformable plates under rapidly growing loads, critical loads and critical time are determined. The influence of the viscoelastic and heterogeneity properties of the material and concentrated masses on the dynamic stability of a rectangular plate is shown. The results obtained are in good agreement with the results and data of other authors.

17. Temperature Condition of Asphalt Concrete During Road Usage

    Milena Telegina, Diana Kirillova, Yuri Lazarev, Vyacheslav Petrov

    Abstract

    The article is devoted to the behavior of asphalt concrete with a change in air temperature. The subject of the study is the temperature regime of asphalt concrete. The aim of this work is to assess the effect of changes in air temperature on the strength characteristics of asphalt concrete and develop proposals to reduce the negative impact on asphalt concrete. This will prevent the occurrence of destructive processes in the pavement coating, supporting the transport and operational performance of roads. And as a result, it will lead to an increase in the service life of roads, which is an urgent task. As a result of the work carried out in laboratory conditions, the dependences of low-temperature voltage are obtained. Based on the calculation, a curve of the annual distribution of the coating temperature is obtained, and the values of extreme temperatures for the city of St. Petersburg are found. Suggestions have been developed to reduce the effect of ambient temperature on the surface of the road surface.

18. Cost and Energy Assessment of Buildings Thermal Protection Level

    Maksim Terekh, Darya Tretyakova, Nadezhda Morozova, Jurģis Zemītis

    Abstract

    In this article, two types of mathematical models for thermal protection level analysis were developed: the economic and energy ones. Both of which allow to calculate the relevant thickness of the selected insulation material under any climatic and economic conditions with any constant layers of building envelope taken from structural considerations. The factors influencing the models were also evaluated. The main factors on which the economic model depends are the costs of energy and insulation material in the region, the region degree-days, the discount rate and the billing period. The key factors to influence the energy model are the region degree-days and the energy consumption rate for the production, transportation and installation of the insulation material. Comparing the two models developed, the following conclusion can be made: The economic model is practically easier to use, as all of the necessary information could be found in the standards, and in the manufacturer catalogs, it allows to get a more precise and accurate result, while the energy approach requires the data, which sometimes has no public access. But, energy model provides us with a more objective assessment when comparing the level of building thermal protection in different countries.