bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soil stabilization with modern TM MAPEI materials in reconstruction of buildings and structures
Authors: Panchenko S V , Vatulia G L , Lobiak O V , Pavliuchenkov M V , Herasymenko O S , Bohdan S M 
Published: December 2019

Abstract
The article deals with the findings of experimental and theoretic research into the efficiency of applying prepared substances TM MAPEI for chemical soil stabilization for foundations of buildings in reconstruction. The objects of the study were soils of rapid, average and slow permeability. Determination of physical and mechanical characteristics of soils before and after stabilization was conducted in laboratory environment. The results were obtained on the basic of the project into stabilization of foundations under complex reconstruction of a four-storied building. The chemical stabilization technology for foundations purported uniform mixing of soil with a special mixing screw, supplying needed components, and further consolidation. A design diagram for the building was made in software package Lira-SAPR 2018. Calculations of carrying capacity of the foundation were made for six design patters which differed in characteristics of the stabilized soil according to the materials applied. The first design pattern considered the application of non-stabilized soil. Results of the calculations are presented as isofields, soil reaction coefficients C1
and C2
, loads (pressure) on the foundation Pz
, and vertical deformations. On the basis of the research the authors state that application of TM MAPEI for chemical stabilization of collapsible soils under reconstruction allows increasing the foundation rigidity by three times and more, the carrying capacity by 10 times and more, depending on the formulations accepted.
Energy resource of reinforced concrete elements and structures for the deformation-force model of their deformation
Authors: Romashko V M , Romashko O V 
Published: December 2019

Abstract
This article provides a critical analysis of existing methods for calculating the residual life of reinforced concrete elements and structures by the rigor of the original problem statement and how it is solved. The most important provisions of the universal method of calculating the residual energy resource of reinforced concrete elements and structures under conditions of long operation are outlined. It is based on the deformation-force model of resistance of reinforced concrete in general and the hypothesis of invariance in unit volume and independence from the mode of loading of potential energy of deformation of reinforced concrete element. This hypothesis is reformed to the energy criterion of exhaust bearing capacity of reinforced concrete elements under different load modes. The implementation of the proposed method for calculating the residual energy resource of the bearing strength capacity of reinforced concrete elements and structures is possible also in a temporary dimension. This can be done using the concrete creep parameters.
Model of multilevel formation of normal cracks in reinforced concrete elements and structures
Authors: Romashko O V , Romashko V M 
Published: December 2019

Abstract
This article proposes a model of multilevel formation of normal cracks. It is based on the most important patterns of adhesion of reinforcement with concrete. The occurrence of the first normal cracks of the first level is calculated by the limiting deformations of stretched concrete, which are fixed by the extreme criterion of its strength. The distances between the cracks are determined by the equilibrium of the maximum forces in the stretched concrete and the forces of active adhesion in the area between the cracks. It is proposed to calculate the force of active coupling by the nonlinear function of the average stresses of this coupling, justified by the power of expression. It is substantiated why for bending reinforced concrete elements the distances between normal cracks of new and previous levels will always differ from each other. In the developed model, the width of the most dangerous normal crack opening is calculated from the positions of successive accumulation of reinforcement and concrete mutual displacements.
Crack resistance of decorative composites
Authors: Dovgan A D , Vyrovoy V M , Dovgan P M 
Published: December 2019

Abstract
The results of a study of crack resistance obtained during the development of fine-aggregate concrete for architectural elements are presented. The crack resistance study of 27 different proportions of compositions was carried out in accordance with DSTU B V.2.7-227: 2009 using experimental statistical modeling methods. Due to the fact that the method of initiating the initial crack in the samples changes the distribution of the technological fields of strain, the tests were carried out on two series of samples. The data obtained show that the crack sealing method changes the deformative-stressed state of the composite. So, crack resistance for one concrete composition can vary, from the conditions of the experiments, from 3 to 40 %. Based on the obtained values of the characteristics of the material, in particular, for the coefficient of technological impact on crack resistance, which describe the fields of these criteria in the coordinates of the factors of concrete composition, models were built. The results of the model are presented on 5 factor diagrams of the form “cubes squared”. An analysis of the constructed diagrams showed that the initial conditions for the organization of the structure of concrete determine its ability to resist the development of various types of cracks. During the introduction of finely dispersed fibers at an optimal dosage of fine sand grains (50 % in a sand mixture) and a slight replacement of cement with zeolite (from 2 to 3.4 %), it is possible to reduce the technological damage to the decorative composite, thereby improving crack resistance.
Mathematical modeling of steel fiber reinforced concrete properties and selecting its effective composition
Authors: Dvorkin L , Bordiuzhenko O , Zhitkovsky V , Marchuk V 
Published: December 2019

Abstract
Design of optimal concrete compositions with specified quality indicators at minimal cost still remains one of the most actual problems. The paper deals with methodology for designing optimal fiber reinforced concrete composition using experimental-statistical models of concrete properties. The obtained mathematical models for compressive and flexural strength of steel fiber reinforced concrete and a model of superplasticizer consumption are used. The proposed method of fiber reinforced concrete composition design takes into account the specific characteristics of the studied materials. It allows relatively easy composition optimization by applying a specific minimum cost criterion. Experimental results obtained in the frame of the study confirm efficiency of the proposed concrete mix design methodology for producing steel fiber reinforced concrete with necessary properties.
Basalt fiber concrete as a new construction material for roads and airfields
Authors: Krayushkina K , Khymeryk T , Bieliatynskyi A 
Published: December 2019

Abstract
The presence of reinforcing fibers in concrete in terms of their optimal content increases density, uniformity and reduces the risk of cracking which allow predicting the increased dynamic resistance, frost resistance, abrasiveness and durability of both cement and asphalt concrete. This article presents the results of experimental studies of the physical-mechanical properties of cement and asphalt concrete reinforced with basalt fiber during which technological indicators of impact on the strength and durability of concrete (fiber content in mixtures, the ratio of fiber length to the size of the largest coarse aggregate) were selected, statistical analysis and optimization of the research results. To justify the choice of basalt fiber, the results of research on the determination of its chemical composition of the fiber and physico-mechanical characteristics are shown. The optimal sizes of basalt fiber, which is introduced into the mixture, are also determined. It was concluded under what conditions the studied characteristics of concrete reinforced with basalt fiber reach their maximum value with the corresponding ratios of technological indicators.
Modified fiber reinforced concrete for industrial floors
Authors: Marushchak U D , Sydor N I , Braichenko S P , Margal I V , Soltysik R A 
Published: December 2019

Abstract
The main requirements to gain of strength, impact resistance without increasing brittleness, durability of concrete for industrial floors are increasing. It has been shown that the strength of concrete at the impact loads can be increased by means of regulation of the macro-, micro- and nanostructure parameters of the concrete. The kinetics of hardening, peculiarities of pore structure and impact resistance of concrete reinforced with polypropylene fiber and modified by polycarboxylate ether superplasticizer, micro- and nanofine mineral additives are investigated. Nanomodified concretes are characterized by increased rate of early strength development (fcm2/fcm28=0.55) and strength after 28 days (101.5–104.9 MPa), which meets the requirements for rapid hardening high strength concrete. Impact resistance of modified fiber reinforced concrete is determined according to special procedure, which estimate parameter of maximum weight after which the residual impression depth on the surface from impact does not exceed the permissible value (2 mm). The impact resistance of concrete modified with polycarboxylate superplasticizer is 100 and 150 N after 28 and 360 days respectively. Nanomodified fiber reinforced concrete is characterized impact resistance 200 N after 28 and 360 days.
Ash-slag binders derived from thermal power plant wastes
Authors: Pavlikov A M , Petrash O V , Popovych N M , Bondar L V 
Published: December 2019

Abstract
This research deals with the Portland cement hydration processes in the presence of chemical additives. The slag-alkyne binders based on bottom ash are under investigation. It has been solved the problem of utilization the wastes from the thermal power plants. The components of slag-alkyne binders have been tested, normal gravity of cement mixture with the additives has been determined, and cement mixture curing period was measured. The possibility of deriving the ash-slag binders of the thermal power plant wastes was discovered. The methods of mathematical experiment planning were applied to assess the influence levels of chemical additives on the properties of alkyne-slag binders. The presented results provide the thermal power plants with a solution to how the industrial wastes can be disposed of in an environmentally friendly fashion. The spreadsheets with research data are provided along with the equations for the binders’ properties correlation with the number of chemical additives used and its fraction in the total composition.
Polymer-cement mortar for protection of buildings against electrical influences
Authors: Pluhin O A , Plugin A M , Nesterenko S G , Plugin D A , Savchenko O M 
Published: December 2019

Abstract
In recent decades, the number of sudden structural failures of buildings and structures being in operation and under construction has increased in the world. Generally, most of the experts associate these failures with the following reasons: design errors; errors and violations made during construction; and poor maintenance. In our opinion, another reason for the sudden structural failure of buildings and structures and the characteristic of the areas where they occur is the periodic accumulation and alteration of excess negative electric charge and the electric field of the Earth in crust fractures zones, near artificial sources of electricity, DC powered transport, rivers and large water reservoirs. To protect buildings and structures in hazardous excess negative charge areas, a polymer-modified mortar was developed based on carbamide resin cured with chlorine iron, with the addition of a superplasticizer and fly ash from thermal power plants. Theoretical, experimental and practical results of the study are provided.
Research of influence of polymer additives-stabilizers on physical-mechanical indicators and microstructure of cement ground
Authors: Solodkyy S J , Novytskyi Y L , Topylko N I , Turba Y V 
Published: December 2019

Abstract
The article describes the positive effect of cement ground modification by polymer stabilizers. The influence of the latex polymer stabilizer Nanoterrasoil, manufactured by NanoSky (Germany), and the polymer acryl-based stabilizer (SAP) on the physico-mechanical parameters of a light sandy loam exposed by Portland cement stabilization has been investigated. The effect of acrylic polymer on the microstructure of the cement ground based on light sandy loam has been studied. It has been established that when introducing the polymer stabilizer Nanoterrasoil (NTS) (1-1.5 wt. %) into the cement-ground mixture with a simultaneous decrease in the cement consumption, the final product - cement ground acquires the increased compression strength (28 days) in water-saturated state and saturation coefficient. Significant increase of physico-mechanical parameters has been established even in case of loam stabilization by acrylic polymer (SAP), even without cement introduction. The cement ground modified with acrylic polymer is characterized by a solid fusion microstructure. This proves that the individual organic ions of the acrylic polymer, when introduced into the cement ground, are adsorbed on the surface of the solid particles of clay minerals, enveloping and bonding them during polymerization, forming a complex organo-mineral system.
Research of the process of spread of fire on beams of wood of fire-protected intumescent coatings
Authors: Tsapko Yu V , Yu Tsapko A , Bondarenko O P , Sukhanevych M V , Kobryn M V 
Published: December 2019

Abstract
The article presents the results of the protection of wooden building structures with intumescent coatings for the resistance to high-temperature flame resistance. The essence of the method of determining the effectiveness of the coating was the impact of standardized flames on fireproof wood and the definition of values. Based on the data obtained, criteria were established that correspond to the degree of damage to the specimens and the increase in the combustion temperature, resulting in a decrease in weight loss. To determine the effectiveness of fire protection in the developed coatings studies on the combustibility of wood in terms of weight loss and flue gas temperature were conducted, and it was found that with coating the degree of damage to the samples in length does not exceed 26%, the degree of damage by mass does not exceed 2% and the flue gas temperature does not exceed 115°C. However, a protective layer that is of considerable thickness to the building structure should be applied to ensure its protection, since, at a higher intensity of thermal action, the fire resistance of the wood may decrease due to the formation of a low coke layer. Full-scale tests using model specimens of wooden beams under the action of a high-temperature flame furnace have shown that the intumescent coating can withstand high temperatures, effectively preventing the penetration of heat into the material due to the formation of a swollen coke layer, which affects the speed and depth of the temperature.
Increasing the durability of fibrous cement compositions by impregnating the porous space of fiber concrete
Authors: Vandolovskyi O G , Rachkovskyi O V , Nalyvayko T A , Nalivayko T T , Gasanov A B 
Published: December 2019

Abstract
Fiberglass reinforcement is the most effective method of increasing the strength of concretes because fiberglass has high mechanical strength and high modulus of elasticity. The low corrosion resistance of fibers to the alkaline environment of concrete plays the role of the limiting factor to the widespread use of fiberglass reinforcement. As the process of corrosion of fiberglass largely depends on the porosity of the composition, the authors have conducted a study of the impregnation of the porous space of the fiberglass by specifically developed compound of the following composition: the liquid component – liquid glass; the neutral filler - nanodispersed silica Kovelos-05; the hardener of liquid – sodium silicofluoride. As a result of the chemical reaction between the liquid glass and the cement clinker components, colloidal calcium hydrosilicate and sodium aluminate are formed. The set of properties of liquid sodium glass enables it to accelerate the setting of concrete at the appearance of sodium aluminate and to reduce the permeability of the porous space, due to the formation of calcium hydrosilicates. These facts led to the use of liquid glass as a compound for impregnation of fiber concrete.
Application of decision–making parametric structures in the analysis of a compound planetary gear
Authors: Deptula A , Drewniak J , Macek W 
Published: December 2019

Abstract
The design process of planetary gears can be divided into two main stages, i.e. conceptual design and construction, that is the preparation of construction documentation. In the first stage, the constructor has a very limited number of project data. In the case of a reduction or multiplier transmission these are usually output parameters (torque and speed), characteristics of the driving and the driven machine, Therefore, the stage of gearbox design must be supported by preliminary calculations, which supports the selection of the correct technical solution, leading to the stage of the structural design preparation. In the method of systematic search, we used an algorithm for generating induction decision trees, based on entropy growth as a method related to machine learning. In the next step, the decision-making parametric structures were employed. In the future, the presented solution will allow further analyses and syntheses such as checking the isomorphism of the proposed solutions, determining the validity of constructions and/or operating parameters of the analysed gears.
Nonlinear model and simulation of a rolling bearing
Authors: Smagala A , Kecik K 
Published: December 2019

Abstract
This paper presents an analysis of a nonlinear model of a rolling bearing with two degrees of freedom. The acceleration response provides information regarding the relationship between vibration and a different number of balls, values of internal clearance and rotary shaft speeds. The acceleration response is higher when the radial internal clearance and the shaft speed increase. When the number of balls increases, the acceleration decreases for the entire range of radial internal clearance. These results are useful for understanding the vibration response mechanism of ball bearings under variable parameters.
Numerical analysis of the rotor in the co-simulation methodology
Authors: Siadkowska K , Raczyński R , Wendeker M 
Published: December 2019

Abstract
The co-simulation method in the composite analysis of the rotor enables connection between Multi Body Dynamics (MBD), Finite Element Method (FEM) and Computational Fluid Dynamics (CFD) by using MATLAB code control algorithms. The idea of unidirectional analysis assumes the use of a rigid rotor model with implemented flexible elements of specific mass-rigidity properties, a special Modal Natural Frequency matrix. In this paper, the MBD model complemented with flexible elements was loaded with inertial forces and additional aerodynamic forces. These aerodynamic forces were determined from CFD analyses considering the aeroelasticity of the rotor blade (static and dynamic characteristics appropriate for a given aerodynamic airfoil). The validation of the computational model was performed on the basis of Virtual Blade Model analyses of the rotor, completed with additional algorithms based on the Blade Element Theory method.
Modelling hydrodynamic characteristics of the underwater glider based on Computational Fluid Dynamics
Authors: Stryczniewicz K , Stryczniewicz W , Szczepaniak R 
Published: December 2019

Abstract
The underwater glider is buoyancy-propelled Autonomous Underwater Vehicle (AUV). Their propulsion relies upon changing their buoyancy with internal pumping systems enabling them upward and downward motion. In the presented paper, the forward gliding motions are generated by hydrodynamic lift forces exerted on a pair of hydroplanes attached to a glider hull. The hydrodynamic characteristics of a glider were determined using Computational Fluid Dynamics (CFD). A 3D model was created for the simulation of flow behaviour in the Baltic Sea. The lift and drag forces distribution at different angles of attack was studied for Reynolds number 105. The flow velocity was 0.5 m·s-1 and the angle of the attack varied from -30° to 30° in steps of 2°. Results from the CFD constitute the basis for the calculation the equations of motions of the glider in 6 degrees of freedom. The vehicle motion simulation will be achieved through numeric integration of the equations of motion. This work will contribute to dynamic modelling and three-dimensional motion simulation of the torpedo-shaped underwater glider.
Design and optimisation methods for interactive mobile VR visualisation
Authors: Skulimowski S , Badurowicz M , Barszcz M , Montusiewicz J 
Published: December 2019

Abstract
The article describes the process of creating a VR mobile application for Google VR platform. The application presents a virtual museum exhibition as part of cross-cultural competence and user interface usability research. The process of creating the application requires taking into account the hardware and software limitations and the specificity of mobile devices. In addition, a higher level of optimisation helps build positive user experience, which is essential in VR applications. The process includes, among others: planning activities, preparing assets, implementing VR vision and interaction modules. The paper includes descriptions of individual steps, problems and other non-standard situations that occurred during the creation and testing of the VR application. In addition the results of the initial performance tests and the methods used to optimise and maintain the stability of the application are presented. By taking into account all of the mentioned factors and the fact that many solutions are yet not well described, the description of the process is expected to provide a point of reference and help for future developers of mobile VR applications.
Neural modelling of cavitation erosion process of 34CrNiMo6 steel
Authors: Szala M , Awtoniuk M 
Published: December 2019

Abstract
Artificial neural networks (ANN) are commonly used to solve many industrial problems. However, their application for cavitation erosion evaluation is a quite new attempt. Thus, the aim of this work was to elaborate the neural model of the cavitation erosion process of 34CrNiMo6 steel. Cavitation erosion tests were conducted with a usage of the ultrasonic vibratory method with stationary specimen that relies on the ASMT G32 standard. The proceeding damage of marked steel surface area was observed by means of a scanning electron microscope. Wear was evaluated with profiler measurements, image analysis of cavitation worn surface areas and weighing done in stated time intervals. The cavitation erosion results were analysed with Matlab software by Neural Network Toolbox. The developed neural model of cavitation erosion process that combines exposure time, roughness, area fraction of worn surfaces, and mass loss gives promising results.