bluuebunny/crossref_metadata_2025_split huggingface dataset:
Calculation of deformations of concrete with indirect reinforcement according to limit state design
Authors: Manaenkov Ivan , Korenkov Pavel , Grezeva Anastasiya S , Zinoveva Ekaterina 
Published: July 2020

Abstract
Currently, the issue of increasing the efficiency of the use of traditional materials in building structures due to rational structural solutions and improving design methods and material models is relevant. The use of indirect reinforcement improves the strength and deformation characteristics of concrete. The article considers the influence of indirect reinforcement in the form of transverse welded meshes on the strength and ultimate compressibility of concrete. The main attention is paid to the determination of the strain values determining the stress-strain diagram for concrete with indirect reinforcement. It is known that with an increase in the strength of concrete, the value of its ultimate compressive strains decreases. Indirect reinforcement can significantly increase the ultimate compressibility of concrete and makes the difference in ultimate deformations even more significant for concrete of different strengths. In this context, when calculating structures in accordance with the limit state design and decreasing the strength values of concrete in order to obtain the necessary security, it is possible to overestimate the ultimate compressibility of concrete. This is unacceptable in calculations based on the deformation model, since the achievement of ultimate deformations of the material is the main criterion for structural failure. To confirm the hypothesis, the results of tests for central compression of concrete with indirect reinforcement in the form of transverse welded meshes were selected. The strain values at the peak of the diagram were calculated for the experimental samples. Calculations were also performed for the characteristic compressive strength values and the design values of strength. The results are compared with experimental data. A significant overestimation of the values of strain at the peak of the diagram was noted in the calculations based on the characteristic compressive strength values and the design values of strength.
Numerical methods in the study of seismic dynamics of underground pipelines
Authors: Bekmirzaev Diyorbek , Mirzaev Ibrakhim , Mansurova Nodirakhon , Kosimov Elbek , Juraev Donitor P 
Published: July 2020

Abstract
A system of equations describing the oscillations of a rectilinear pipeline that interacts with the surrounding soil in the case of seismic action functioning in an arbitrary direction is presented. A numerical implementation of problems related to the determination of the mode of deformation of a pipeline experiencing seismic movement of the soil is performed. The methods of realization of boundary problem of seismodynamics of underground pipelines at arbitrary direction of seismic load are developed, as well as the methods of realization of the problems of seismodynamics of underground pipelines of non-orthogonal configuration, based on Finite deference method.
Statistical analysis of yield strength spectrum from nanoindentation for identification of constituent phases in steel
Authors: Pham Thai-Hoan , Nguyen Ngoc-Vinh 
Published: July 2020

Abstract
In this study, the extension of the statistical analysis application into yield strength of constituent phases of steel was conducted. A larger number of nanoindentation tests was carried out on a type of popular structural steel SS400. The mechanical properties, such as elastic modulus, hardness, and yield strength of the indented material were extracted from nanoindentation load-depth curves. The statistical analysis was then applied to analysis the material properties spectra. The experimental and analysis results revealed that the yield strength spectrum obtained from nanoindentation tests can be used in the accurate and reliable identification of the constituent microstructural phases and their strength in structural steel by applying statistical deconvolution analysis. For the present steel, three microstructural phases are known as low characteristic ferrite, high characteristic ferrite, and pearlite with the corresponding yield strength value of
a

y
= 296.1 ± 30.8 MPa,
a

y
= 423.6 ± 34.3 MPa, and
a

y
= 573.1 ± 38.9, respectively.
Reliability assessment of Buckling Strength for Battened Built-up Columns steel considering shear deformations
Authors: Tran Ngoc-Long , Nguyen Trong-Ha , Phan Van-Phuc 
Published: July 2020

AbstractBattened built-up columns are widely used in steel construction especially when the effective lengths are great and the compression forces light. The buckling strength of this structure depends hugely on the material properties, geometry dimensions and also the flexural deformations both of the chords so the battens must be considered in order to derive the shear stiffness. The input parameters are potentially random sources. This research presents an assessment of the safety for Buckling Strength for Battened Built-up Columns steel considering shear deformations. Reliability of the structure is evaluated using Monte Carlo simulation method. Effects of input parameters are also investigated.
Granular material pressure to reinforced concrete walls of cylindrical slender silos: Analysis and Experimental studies according to Eurocodes
Authors: Tuan Trung Nguyen , Truong Thang Nguyen , Tung Vo Manh 
Published: July 2020

Abstract
Silos act as storage structures used for containing granular materials. The solids-induced loads acting on the walls and internals of silos are not easily determined, and inconsistent between commonly used design codes. This paper presents principles and a brief description of Eurocode standard to determine the solids-induced loads acting on reinforced concrete (RC) walls of cylindrical slender silos. That code is being considered as the most complete and modern standard for silo design up to now. A calculation example is provided to clarify the procedure. An experimental program was conducted to determine the friction coefficients between some granular materials and RC walls. The experimental results show that the values introduced in Eurocode can be used reliably.
Nonlinear integro-differential equations of bending of physically nonlinear viscoelastic plates
Authors: Indiaminov Ravshan , Butaev Ruslan , Isayev Nurbek , Ismayilov Kubaymurat , Yuldoshev Bakhtiyor , Numonov Akhrorbek 
Published: July 2020

Abstract
An important feature of real materials is the nonlinear nature of the relationship between stress and strain. Taking into account such features of deformation of structural materials in the calculation allows us to bring theoretical forecasts closer to their real behavior. Physical nonlinearity is due to the calculation in the calculation of the nonlinear dependence between the components of the generalized stresses and strains characterizes the work of the structural material in the elastoplastic region. Many structural elements of modern technology are made in the form of plates of various shapes. The widespread use of plates is explained by their high strength, considerable rigidity and relatively low weight, which, along with the manufacturability of manufacturing, distinguishes them among other structural elements. A constant trend in the development of technology is an increase in the intensity of dynamic effects, accompanied by an increase in the level of vibration.
Stress-strain state of expansive soils when soaking from above
Authors: Yarkin Viktor , Lobacheva Nataliia 
Published: July 2020

Abstract
The article proposes a method for determining additional vertical stresses at any point in the massive of expansive soil, which arise from the weight of unmoistened soil outside the soaking area. A comparison of the results of research stress-strain state of expansive soils when soaking from above, obtained by the proposed method, the finite element method and in accordance with current regulatory documents. The proposed regularity of the distribution of additional stresses from the weight of unmoistened soil outside the soaking area in horizontal sections of the flooded zone is confirmed by the results of numerical studies by the finite element method. For a vertical line passing through the center of the flooded zone, the proposed method gives results that are almost identical to the current regulatory documents. The application of this method allows more accurate determination of the swelling surface, taking into account the unevenness of the geological structure, the shape of the flooded zone and stress fields, and determining the forced displacements of the base or equivalent loads when calculating structures interacting with expansive soil. The conditions are determined under which it is advisable to simulate the impact on the building from the side of swelling soil by equivalent loads acting from the base.
Numerical investigation of the aerodynamic coefficients for the steelmaking shop
Authors: Tusnina Olga , Kolyago Alexey 
Published: July 2020

Abstract
The wind load on the building depends on its shape and size, type of terrain, climatic region and a number of other factors. In accordance with Russian standards for buildings with a high level of responsibility, it is required to determine the wind load either experimentally in a wind tunnel, or using numerical simulation by solving three-dimensional problems of fluid dynamics. The article presents the results of the numerical determination of aerodynamic coefficients for the building of the steelmaking shop, made using the Abaqus software package. The steelmaking shop has a complex shape in plan and uneven in height, it is a particularly dangerous production facility and refers to structures with a high level of responsibility. The aerodynamic coefficients on the walls and roof of the steelmaking shop obtained by CFD analysis are represented. The different meshes are analyzed. Regulatory method to calculate aerodynamics coefficient also may be adopted for this building. The values of the coefficients by regulatory procedure are on average greater than those numerically obtained. The wind load does not have a significant effect on the framework of the steelmaking shop, since the efforts from the wind load are not more than 10% of the maximum total effort in the elements, while the efforts from the crane load are up to 45% of the total effort, and from the technological loads up to 50% of the total effort. So, using the regulatory procedure for bearing capacity analysis of framework of the steelmaking shop is also possible.
A simplified approach in determining the c and φ for asphalt mixtures
Authors: Van Phuc Le  , Hung Nguyen Van , Phuc Nguyen Quang 
Published: July 2020

Abstract
In this study, using the Mohr-Coulomb failure theory, a simplified method was proposed to determine the cohesion (c) and internal friction angle (φ) for asphalt mixtures based on direct tension (DT) strength and indirect tension (IDT) strength or unconfined compressive strength (UCS) and IDT strength. The direct tension (DT) strength, superpave indirect tension (IDT) strength and unconfined compressive strength (UCS) were conducted to verify this method using three asphalt mixtures. It was found that the determination of c and φ values have mean absolute errors of 5.2% and 1.8%, respectively in comparing two methods indicating that the c and φ can be estimated from DT strength and IDT strength or IDT strength and UCS. Further study is recommended to verify using different binder grades and mixture types.
Mathematical Model of Mass Transfer Processes in Biological Corrosion of Cement Concretes
Authors: Fedosov Sergey , Rumyantseva Varvara , Konovalova Viktoriya , Loginova Svetlana 
Published: July 2020

Abstract
Timely protection of underwater concrete and reinforced concrete objects from biofouling will significantly reduce the economic damage from the effects of corrosion damage, improve the reliability of structures operated in high humidity conditions, and reduce the likelihood of accidents. Despite the abundance of ways to protect against fouling, there are still no radical methods of struggle. It is expedient to find a solution to the problem of predicting the durability of concrete and reinforced concrete structures in biologically aggressive liquid media from the point of view of the theory of mass transfer. The model of mass transfer in an unlimited two-layer plate is considered for the first time in the form of a system of partial differential equations of parabolic type with boundary conditions of the second kind at the interface between concrete and liquid and the fourth kind at the interface between concrete and biofilm, which describes diffusion processes in the system of «cement concrete – biofilm – liquid». The proposed physical and mathematical model takes into account the properties of the solid and liquid phases, as well as the kinetics of growth, reproduction and death of microorganisms. The results of calculating dimensionless concentrations of «free» calcium hydroxide over the thickness of the concrete structure and biofilm are presented. The application of the obtained solutions will allow timely monitoring of the biocorrosion destruction of underwater structures and select effective protection methods.
Penalty function method for imposing nonlinear multi freedom and multi node constraints in finite element analysis of frame systems
Authors: Bich Quyen Vu Thi , Ngoc Tien Dao , Nhu Dung Nguyen , Quoc Khanh Cao 
Published: July 2020

Abstract
This paper focuses on the treatment of nonlinear multi-freedom and multi-point boundary condition in finite element analysis of frame systems. The treatment of boundary constraints is required to produce modified system of equations based on master stiffness equations considering nonlinear constraints. For imposing nonlinear multi freedom and multi point constraints, the Penalty Augmentation method and Lagrange Multiplier Adjunction method are better in many applications. In present paper, the Penalty Augmentation method is using for implementation of nonlinear boundary constraints. The nonlinear relationship considerably increases the difficulty in constructing and solving the modified system of equations. The Newton Raphson method, have been the most powerful and popular method for solution of nonlinear equations, is used for solving studied problem. Using the Newton Raphson technique, this paper develops the incremental-iterative algorithm to solve the nonlinear modified system of equations. Based on the presented algorithm, the paper proposed calculation procedure and established programs for determining internal forces and displacements of frames having nonlinear multi freedom and multi point constrains boundary. The numerical test results using the proposed method show the efficiency and reliability of proposed algorithm.
Joint work of layers of different strengths in reinforced concrete multi-layered construction at compression
Authors: Berlinov Mikhail , Berlinova Marina 
Published: July 2020

Abstract
Currently, a lot of attention in the construction industry is given to the issues of ensuring the reliability of reinforced concrete structures at all stages, both manufacturing, design and operation. In this regard, this article conducted a study of the reliability and durability of multi-layered structures with a monolithic connection of layers in order to reduce the own weight of such elements and the cost of construction and repair. The method of determining the average strength in the section of the element is presented, which allows the forecast of the durability of multi-layered reinforced concrete structures and allows to determine the overall work of each component, regardless of their number and the moment connection time, as well as defects in the manufacture and damage caused during operation, various physical-mechanical and reological characteristics of materials of layers of multi-layered structure, actual tense-deformed multi-layered parts as they work together. The presented method of calculation is based on the fundamental dependence of stresses and deformations in concrete, applied to a compressed multi-layered element.
Impact of the idle run of a rotating easily dumped structure on pressure in the room
Authors: Gorev V A , Korolchenko Anton 
Published: July 2020

Abstract
The work addresses the alternative use of window sashes as an easily dumped structure (EDS) with window casement rotation to ensure gas release from the room and pressure venting. The paper focuses on the use of the option with one outside rotating casement as EDS while the other part of the window sash can be opened inside or be immobile. The work records equations for the movement of a swivelling safety structure and changes in pressure in a dimensionless form with identified dimensionless complexes, which equivalence ensures the likeness of aperture opening. The study is limited to the idle run period. It was demonstrated that with small room volumes, the idle run must be taken into account and its impact on a pressure growth must be reduced. The work shows ways to reduce the idle run time.
Silos and warehouses complexes in five locations in Tanzania – case studies
Authors: Maria Kulczycki Paweł 
Published: July 2020

Abstract
In the end of 2016 National Food Reserve Agency of Tanzania (NFRA) ordered from Polish company FEERUM S.A. implementation of grain silo projects, production of designed silos, ensuring their transport to Tanzania, assembly and commissioning. Structure design of silo complexes was ordered from the design office, the subcontractor – TEK Projekt. The paper describes various aspects of data acquisition, design and execution of foundation works from the point of view of Central European contractor in Africa. In general it ends up with a kind of wake-up call to open designers eyes for situation of different countries and people, improving general knowledge about world problems.
Computer simulation of fracture dynamics in a fiber-reinforced composite
Authors: Abdukadirov Sagdulla , Buriev Abdulaziz , Ayzenberg-Stepanenko Mark 
Published: July 2020

Abstract
Calculation models are developed to examine dynamic stress concentration and fracture in a plane elastic fiber-reinforced composite sheet. The sheet consists of a regular system of alternating extensible fibers and pliable adhesive layers. In calculations, special algorithms are built preventing or minimizing parasite distortions caused by the mesh dispersion. Two engineering models of the adhesive are considered: (i) inertionless bonds of constant stiffness, and (ii) an inertial medium perceived shear stresses. Clarified solutions of the problem are obtained in the case that the sheet pre-stretched along fibers.
Behaviour and Calculation of Polymer Pipelines Under Real Earthquake Records
Authors: Nishonov Nematilla , Bekmirzaev Diyorbek , An Ekatirina , Urazmukhamedova Ziyoda , Turajonov Kodirjon 
Published: July 2020

Abstract
The effect of real records of several earthquakes on polymer pipeline vibrations are studied and analyzed in the paper. Longitudinal vibrations of straight end section of the underground pipeline are considered using the Kelvin-Voigt model. To solve the equation, the method of finite differences of the second order of accuracy is used. An algorithm has been compiled and on its basis a software product has been developed for the numerical calculation of an underground polymer pipeline under the effect of real seismograms recorded in different cities of the world. The stress-strain state (SSS) of polymer pipelines is determined under various boundary conditions.
The dynamic effect in a structural adjustment of reinforced concrete structural system
Authors: Fedorova Nataliya , Kolchunov Vitaliy , Tuyen Vu Ngoc , Dinh Quoc Phan , Medyankin Mihail 
Published: July 2020

Abstract
Results of experimental and theoretical studies of the dynamic effect of reinforced concrete structural system of building in case of its sudden structural adjustment caused by special accident action in the form of hypothetical removal of one of bearing structures are given. A zone of possible local failure of the structural system is modeled by a fragment of the structural system adjacent to that zone. For such a fragment called a substructure, an analytical solution of the problem for determining the time of dynamic loading of fragment elements is obtained. Evaluation of theoretical solution for determination of dynamic parameters of frame structural system at the considered action is performed by comparison of theoretical results with data of experimental studies of the fragment of a reinforced concrete multistory frame.
Rigid inclusion ground improvements as an alternative to pile foundation
Authors: Polańska Bernadetta , Rainer Jakub 
Published: July 2020

Abstract
The new buildings are very often planted in places where the soil is weak or unbearable. Their occurrence eliminates the possibility of shallow foundation. In such cases, it is necessary to make the ground stronger or to make a deep foundation. The paper presents a comparison of the method of the soil reinforcement with rigid concrete columns and deep foundation on piles. Features that combine both methods are presented, as well as advantages and disadvantages of both methods. The next part of the paper describes the basic calculation methods of the subsoil reinforcement with concrete columns. The work is finished with a case study describing an object located in southern Poland, where originally designed foundation piles in CFA technology were replaced by rigid columns made in the same technology.
Optimization of the duration of the pioneer construction period
Authors: Oleinik Pavel , Kuzmina Tatyana , Zueva Diana , Balmashnova Mariya 
Published: July 2020

Abstract
The construction of facilities in hard-to-reach and underdeveloped areas is an extremely difficult task, the solution of which largely depends on the quality and timely development of the construction area. Significant reserves for reducing the territories pioneer duration are in the combination of the pioneer construction and preparatory periods. To this end, on the basis of a generalization of practical experience, a methodology for linking work is proposed, based on the found equations of communication between the scope of work, the intensity of consumption of labor and technical resources, and the duration of work. The options for changing the scope of work: from the minimum size of the work area per team to the full work area for the whole process are examined and the conditions for rational combination of the pioneer construction and preparatory periods are disclosed.