Pub Date : 2022-12-15DOI: 10.22363/1815-5235-2022-18-6-490-502
N. Androsova, V. Kolchunov, S. Emelyanov
The problems of non-equilibrium and nonlinear processes in the evaluation of reinforced concrete structural systems robustness potential in ultimate states are considered. The definition of concept of “robustness exposition” is given for a quantitative assessment of the robustness potential. A calculation model based on the generalization of the well-known classical relationship between the current relative deficit change rate of the reinforced concrete stress-strain state with respect to each fixed time value is proposed to describe in time non-equilibrium processes of structural materials force resistance depending on the mode and level of loading. On the basis of the linear creep theory, aging materials, an algorithm was developed to determine the measure of creep, corrosion-damaged concrete and reinforced concrete and to determine the parameter “robustness exposition” of a reinforced concrete statically indeterminate structural system, taking into account non-equilibrium and nonlinear processes of its deformation in time. An example of a single-span rigidly clamped reinforced concrete beam calculating the robustness potential from the position of a special limiting state criterion is considered.
{"title":"Non-equilibrium and nonlinear processes in robustness potential evaluation of reinforced concrete structural systems in ultimate states","authors":"N. Androsova, V. Kolchunov, S. Emelyanov","doi":"10.22363/1815-5235-2022-18-6-490-502","DOIUrl":"https://doi.org/10.22363/1815-5235-2022-18-6-490-502","url":null,"abstract":"The problems of non-equilibrium and nonlinear processes in the evaluation of reinforced concrete structural systems robustness potential in ultimate states are considered. The definition of concept of “robustness exposition” is given for a quantitative assessment of the robustness potential. A calculation model based on the generalization of the well-known classical relationship between the current relative deficit change rate of the reinforced concrete stress-strain state with respect to each fixed time value is proposed to describe in time non-equilibrium processes of structural materials force resistance depending on the mode and level of loading. On the basis of the linear creep theory, aging materials, an algorithm was developed to determine the measure of creep, corrosion-damaged concrete and reinforced concrete and to determine the parameter “robustness exposition” of a reinforced concrete statically indeterminate structural system, taking into account non-equilibrium and nonlinear processes of its deformation in time. An example of a single-span rigidly clamped reinforced concrete beam calculating the robustness potential from the position of a special limiting state criterion is considered.","PeriodicalId":32610,"journal":{"name":"Structural Mechanics of Engineering Constructions and Buildings","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42481410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-15DOI: 10.22363/1815-5235-2022-18-6-584-596
Viktor S. Fedorov, Valery E. Levitsky, E. Isaeva
In the development of the ideas and approaches to the analysis of the force resistance of concrete of V.M. Bondarenko, the initial prerequisites for the model of the thermomechanical state of concrete under short-term sharp high-temperature exposure, characteristic of fire conditions, are formulated. The separation of force deformations into components is carried out on the basis of the connection with the accumulation of damage in the structure of the material, based on the principle of independence of the limiting structural stresses from temperature and the mode of force action, which makes it possible to establish basic thermomechanical relationships and determine the deformation parameters of concrete operating under conditions of unsteady heating in a loaded state. Based on the extension of the hypothesis of entropy damping of nonequilibrium processes to the area of action of an active destructive factor, the principle of normalization was formulated and a kinetic equation was proposed, from the solution of which exponential dependences having a single structure were obtained, which make it possible to describe the basic temperature parameters of concrete, the relationship of stresses with deformations, and other nonlinear characteristics. The application of the proposed principles creates a reliable theoretical basis for describing the mechanisms of thermal resistance of concrete and greatly simplifies the modeling of the effect of high temperature on the properties of concrete in the practical implementation of methods for the numerical calculation of reinforced concrete structures.
{"title":"Basic principles in the theory of force and thermal force resistance of concrete","authors":"Viktor S. Fedorov, Valery E. Levitsky, E. Isaeva","doi":"10.22363/1815-5235-2022-18-6-584-596","DOIUrl":"https://doi.org/10.22363/1815-5235-2022-18-6-584-596","url":null,"abstract":"In the development of the ideas and approaches to the analysis of the force resistance of concrete of V.M. Bondarenko, the initial prerequisites for the model of the thermomechanical state of concrete under short-term sharp high-temperature exposure, characteristic of fire conditions, are formulated. The separation of force deformations into components is carried out on the basis of the connection with the accumulation of damage in the structure of the material, based on the principle of independence of the limiting structural stresses from temperature and the mode of force action, which makes it possible to establish basic thermomechanical relationships and determine the deformation parameters of concrete operating under conditions of unsteady heating in a loaded state. Based on the extension of the hypothesis of entropy damping of nonequilibrium processes to the area of action of an active destructive factor, the principle of normalization was formulated and a kinetic equation was proposed, from the solution of which exponential dependences having a single structure were obtained, which make it possible to describe the basic temperature parameters of concrete, the relationship of stresses with deformations, and other nonlinear characteristics. The application of the proposed principles creates a reliable theoretical basis for describing the mechanisms of thermal resistance of concrete and greatly simplifies the modeling of the effect of high temperature on the properties of concrete in the practical implementation of methods for the numerical calculation of reinforced concrete structures.","PeriodicalId":32610,"journal":{"name":"Structural Mechanics of Engineering Constructions and Buildings","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68268662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-30DOI: 10.22363/1815-5235-2022-18-4-375-386
O. Aleshina, V. N. Ivanov, David Cajamarca-Zuniga
Works on the study of the stress-strain state of the shell of an equal slope with an ellipse at the base have not been widely performed. The present paper is a part of a series of articles on the analysis of the geometry and stress state of torses of an equal slope with a directrix ellipse by various methods under different loads and support conditions. The derivation of the differential equations of equilibrium of the momentless theory of shells for determining internal forces in the torse with a directrix ellipse under the action of internal pressure is presented. The analytical results are compared with results obtained by the finite element method (FEM) and the variational difference method (VDM). The advantages and disadvantages of three calculation methods are determined, and it is established that VDM results are more accurate compared to FEM, but FEM-based software is a more powerful tool to perform the structural analysis.
{"title":"Comparative analysis of the stress state of an equal slope shell by analytical and numerical methods","authors":"O. Aleshina, V. N. Ivanov, David Cajamarca-Zuniga","doi":"10.22363/1815-5235-2022-18-4-375-386","DOIUrl":"https://doi.org/10.22363/1815-5235-2022-18-4-375-386","url":null,"abstract":"Works on the study of the stress-strain state of the shell of an equal slope with an ellipse at the base have not been widely performed. The present paper is a part of a series of articles on the analysis of the geometry and stress state of torses of an equal slope with a directrix ellipse by various methods under different loads and support conditions. The derivation of the differential equations of equilibrium of the momentless theory of shells for determining internal forces in the torse with a directrix ellipse under the action of internal pressure is presented. The analytical results are compared with results obtained by the finite element method (FEM) and the variational difference method (VDM). The advantages and disadvantages of three calculation methods are determined, and it is established that VDM results are more accurate compared to FEM, but FEM-based software is a more powerful tool to perform the structural analysis.","PeriodicalId":32610,"journal":{"name":"Structural Mechanics of Engineering Constructions and Buildings","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42231428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-30DOI: 10.22363/1815-5235-2022-18-4-387-395
I. Mamieva
An opportunity of conversion of algebraic surfaces with a main frame from three superellipses of general type into ruled surfaces of several views is shown. It is necessary to take one, two, or all of three superellipses in the form of a rhombus, i.e. it is necessary to assume exponents in explicit algebraic equations of suitable superellipses equal to one. It was illustrated that having taken one and the same main frame from three plane curves lying in the main coordinate planes, one can construct three algebraic surfaces of different orders. So, it is possible to introduce into practice great number of ruled surfaces with the preliminary given main frame from three superellipses. Some of them must be in the form of straight lines. As a result, fifteen shapes, i.e. five threes of ruled algebraic surfaces with a main frame from three superellipses were obtained with the help of three explicit equations or with the help of three systems of parametric equations. These surfaces contain a polyhedron on given rhombus plane, some types of cylindroids and conoids, and ruled surfaces not described in scientific literature before. All surfaces were visualized for concrete examples. Earlier, Professor A.V. Korotich introduced into practice a new group of surfaces which he called “Ruled quasipolyhedrons from conoids.” Some of the ruled algebraic surfaces presented in this paper can be put in this group of ruled quasipolyhedrons.
{"title":"Ruled algebraic surfaces with a main frame from three superellipses","authors":"I. Mamieva","doi":"10.22363/1815-5235-2022-18-4-387-395","DOIUrl":"https://doi.org/10.22363/1815-5235-2022-18-4-387-395","url":null,"abstract":"An opportunity of conversion of algebraic surfaces with a main frame from three superellipses of general type into ruled surfaces of several views is shown. It is necessary to take one, two, or all of three superellipses in the form of a rhombus, i.e. it is necessary to assume exponents in explicit algebraic equations of suitable superellipses equal to one. It was illustrated that having taken one and the same main frame from three plane curves lying in the main coordinate planes, one can construct three algebraic surfaces of different orders. So, it is possible to introduce into practice great number of ruled surfaces with the preliminary given main frame from three superellipses. Some of them must be in the form of straight lines. As a result, fifteen shapes, i.e. five threes of ruled algebraic surfaces with a main frame from three superellipses were obtained with the help of three explicit equations or with the help of three systems of parametric equations. These surfaces contain a polyhedron on given rhombus plane, some types of cylindroids and conoids, and ruled surfaces not described in scientific literature before. All surfaces were visualized for concrete examples. Earlier, Professor A.V. Korotich introduced into practice a new group of surfaces which he called “Ruled quasipolyhedrons from conoids.” Some of the ruled algebraic surfaces presented in this paper can be put in this group of ruled quasipolyhedrons.","PeriodicalId":32610,"journal":{"name":"Structural Mechanics of Engineering Constructions and Buildings","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42802503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-30DOI: 10.22363/1815-5235-2022-18-4-307-316
Sergey V. Yuriev
The results of data analysis from complex field studies of vertical deformations of the rock base near-contact layer and full settling Boguchanskaya HPP concrete dam sections in order to determine the state of contact of the foot of the concrete dam with the rock base are presented. The purpose of the study is to control the state of the contact of the concrete dam foot with the foundation based on the analysis of a set of field studies of the vertical deformations of the near-contact zone of the foundation of the concrete dam sections and the total draft of the sections of the concrete dam to justify the stability of the concrete dam sections. In order to control the vertical deformations of the near-contact zone of the rock foundation, string control and measuring equipment (displacement sensors PLPS-10) was installed. The total draft of the concrete dam sections is measured by means of ceiling marks installed in the grout gallery. Analysis of the field data on total drafts of concrete dam sections and vertical deformations of the near-contact section of the rock foundation showed that the contact joint between the foot of the concrete dam sections and the foundation is in vertical compression. The results of the analysis of the available data of complex studies of vertical deformations of the near-contact layer of the rock foundation and the total draft of the concrete dam sections made it possible to substantiate the stability of the concrete dam sections.
{"title":"Analysis of the field studies of the foundation deformations and total draft of the Boguchansk HPP concrete dam","authors":"Sergey V. Yuriev","doi":"10.22363/1815-5235-2022-18-4-307-316","DOIUrl":"https://doi.org/10.22363/1815-5235-2022-18-4-307-316","url":null,"abstract":"The results of data analysis from complex field studies of vertical deformations of the rock base near-contact layer and full settling Boguchanskaya HPP concrete dam sections in order to determine the state of contact of the foot of the concrete dam with the rock base are presented. The purpose of the study is to control the state of the contact of the concrete dam foot with the foundation based on the analysis of a set of field studies of the vertical deformations of the near-contact zone of the foundation of the concrete dam sections and the total draft of the sections of the concrete dam to justify the stability of the concrete dam sections. In order to control the vertical deformations of the near-contact zone of the rock foundation, string control and measuring equipment (displacement sensors PLPS-10) was installed. The total draft of the concrete dam sections is measured by means of ceiling marks installed in the grout gallery. Analysis of the field data on total drafts of concrete dam sections and vertical deformations of the near-contact section of the rock foundation showed that the contact joint between the foot of the concrete dam sections and the foundation is in vertical compression. The results of the analysis of the available data of complex studies of vertical deformations of the near-contact layer of the rock foundation and the total draft of the concrete dam sections made it possible to substantiate the stability of the concrete dam sections.","PeriodicalId":32610,"journal":{"name":"Structural Mechanics of Engineering Constructions and Buildings","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46795551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-30DOI: 10.22363/1815-5235-2022-18-4-329-340
S. Savin, N. Fedorova
The paper provides the conclusions of a comparative analysis of various approaches, design models, methods for analysis of a loaded structural system and the results of such analysis for a sudden failure of a structural member. It shows that the analysis methods recommended by Russian and foreign standards are based on the same methodology. And the recommended options for choosing secondary design schemes in static, quasi-static and dynamic formulations have different complexity, however, give results which are close enough and acceptable for practical purposes. Some differences in the results are associated with different approaches to consider the reaction redistribution time for the removed structural member, i.e., in essence, with the mode of failure of this member. The issue of criteria for a special limiting state is also discussed. The authors present the expediency of including an additional criterion in regulatory documents that considers the second-order effects on the buckling of the structural elements under accidental impacts and, accordingly, provisions for protecting structural systems against the exhaustion of the bearing capacity due to the loss of stability. As such criterion, the achievement of the limiting equilibrium point on the diagram “axial force vs. transverse deflection” can be adopted.
{"title":"Comparison of methods for analysis of structural systems under sudden removal of a member","authors":"S. Savin, N. Fedorova","doi":"10.22363/1815-5235-2022-18-4-329-340","DOIUrl":"https://doi.org/10.22363/1815-5235-2022-18-4-329-340","url":null,"abstract":"The paper provides the conclusions of a comparative analysis of various approaches, design models, methods for analysis of a loaded structural system and the results of such analysis for a sudden failure of a structural member. It shows that the analysis methods recommended by Russian and foreign standards are based on the same methodology. And the recommended options for choosing secondary design schemes in static, quasi-static and dynamic formulations have different complexity, however, give results which are close enough and acceptable for practical purposes. Some differences in the results are associated with different approaches to consider the reaction redistribution time for the removed structural member, i.e., in essence, with the mode of failure of this member. The issue of criteria for a special limiting state is also discussed. The authors present the expediency of including an additional criterion in regulatory documents that considers the second-order effects on the buckling of the structural elements under accidental impacts and, accordingly, provisions for protecting structural systems against the exhaustion of the bearing capacity due to the loss of stability. As such criterion, the achievement of the limiting equilibrium point on the diagram “axial force vs. transverse deflection” can be adopted.","PeriodicalId":32610,"journal":{"name":"Structural Mechanics of Engineering Constructions and Buildings","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47436077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-30DOI: 10.22363/1815-5235-2022-18-4-283-296
V. Erofeev
Energy saving, operational reliability of buildings and structures for various purposes is determined by the durability of building materials and products used in their construction. To date, frame building composites have been developed on the basis of polystructural theory. The frame technology for the manufacture of building products consists in the preliminary manufacture of frames from coarse-pored mixtures, followed by filling voids in the hardened frame with a matrix-plasticized binder, fine-dispersed or fine-grained composition, while the frames and matrix can be formed on various binders. This technology makes it possible to obtain building materials and products with a combination of the most diverse and even incompatible binders with a predetermined set of properties, i.e. opens the way to directional materials science. The paper presents the results of theoretical research and calculation of the technological physical and mechanical properties of frame composite building materials. The regularities of the structure formation of frame composites at the level of the formation of frames and matrices, as well as when they are combined, are revealed. It is established that the process of impregnating the frame with a matrix obeys the laws of motion of freely dispersed or connected dispersed systems. Formulas for calculating structural stresses in hardening frame composites are derived. Analytical dependences for calculating the thermal conductivity coefficient of products are obtained from phenomenological positions. Expressions for the calculation of the modulus of elasticity are obtained for models of ordered aggregates and the kinetics of the processes of destruction of frame composites under their loading is shown. Theoretical dependences for calculating the diffusion coefficient in frame composites on the main structure-forming factors are established.
{"title":"Fundamentals of technology theory of production, calculation physical and mechanical properties and indicators chemical and biological properties of frame building composites","authors":"V. Erofeev","doi":"10.22363/1815-5235-2022-18-4-283-296","DOIUrl":"https://doi.org/10.22363/1815-5235-2022-18-4-283-296","url":null,"abstract":"Energy saving, operational reliability of buildings and structures for various purposes is determined by the durability of building materials and products used in their construction. To date, frame building composites have been developed on the basis of polystructural theory. The frame technology for the manufacture of building products consists in the preliminary manufacture of frames from coarse-pored mixtures, followed by filling voids in the hardened frame with a matrix-plasticized binder, fine-dispersed or fine-grained composition, while the frames and matrix can be formed on various binders. This technology makes it possible to obtain building materials and products with a combination of the most diverse and even incompatible binders with a predetermined set of properties, i.e. opens the way to directional materials science. The paper presents the results of theoretical research and calculation of the technological physical and mechanical properties of frame composite building materials. The regularities of the structure formation of frame composites at the level of the formation of frames and matrices, as well as when they are combined, are revealed. It is established that the process of impregnating the frame with a matrix obeys the laws of motion of freely dispersed or connected dispersed systems. Formulas for calculating structural stresses in hardening frame composites are derived. Analytical dependences for calculating the thermal conductivity coefficient of products are obtained from phenomenological positions. Expressions for the calculation of the modulus of elasticity are obtained for models of ordered aggregates and the kinetics of the processes of destruction of frame composites under their loading is shown. Theoretical dependences for calculating the diffusion coefficient in frame composites on the main structure-forming factors are established.","PeriodicalId":32610,"journal":{"name":"Structural Mechanics of Engineering Constructions and Buildings","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48467967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-30DOI: 10.22363/1815-5235-2022-18-4-317-328
L. Akhtyamova, B. Yazyev, A. Chepurnenko, L. Sabitov
The study proposes a technique for optimizing trihedral lattice tower structures from the condition of maximum critical load. Towers with a cross section of elements in the form of round pipes are considered. The load is represented by a horizontal concentrated force at the upper end of the tower, simulating the operation of a wind turbine. A constraint on the constancy of the mass of the structure is introduced. The variable parameters are the width of the tower, which varies in height, the height of the panels, the external diameters of the cross-section of the chords and lattice. The solution of the nonlinear optimization problem is performed in the MATLAB environment using the Optimization Toolbox and Global Optimization Toolbox packages. A tower of constant width is taken as the initial approximation. The calculation of the critical load is performed by the finite element method in a linear formulation by solving the eigenvalue problem. To solve the nonlinear optimization problem, the interior point method, the pattern search method and the genetic algorithm are used. The efficiency of the listed methods is compared. It has been found that the interior point method is the most efficient. The critical load for the optimal tower compared to the tower of constant width with the same mass increased by 2.3 times.
{"title":"Trihedral lattice supports geometry optimization according to the stability criterion","authors":"L. Akhtyamova, B. Yazyev, A. Chepurnenko, L. Sabitov","doi":"10.22363/1815-5235-2022-18-4-317-328","DOIUrl":"https://doi.org/10.22363/1815-5235-2022-18-4-317-328","url":null,"abstract":"The study proposes a technique for optimizing trihedral lattice tower structures from the condition of maximum critical load. Towers with a cross section of elements in the form of round pipes are considered. The load is represented by a horizontal concentrated force at the upper end of the tower, simulating the operation of a wind turbine. A constraint on the constancy of the mass of the structure is introduced. The variable parameters are the width of the tower, which varies in height, the height of the panels, the external diameters of the cross-section of the chords and lattice. The solution of the nonlinear optimization problem is performed in the MATLAB environment using the Optimization Toolbox and Global Optimization Toolbox packages. A tower of constant width is taken as the initial approximation. The calculation of the critical load is performed by the finite element method in a linear formulation by solving the eigenvalue problem. To solve the nonlinear optimization problem, the interior point method, the pattern search method and the genetic algorithm are used. The efficiency of the listed methods is compared. It has been found that the interior point method is the most efficient. The critical load for the optimal tower compared to the tower of constant width with the same mass increased by 2.3 times.","PeriodicalId":32610,"journal":{"name":"Structural Mechanics of Engineering Constructions and Buildings","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43014990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-30DOI: 10.22363/1815-5235-2022-18-4-297-306
V. Kolchunov, O. Bushova
In order to increase plasticity during destruction along inclined sections and to protect against progressive collapse of reinforced concrete frames of multi-storey buildings, a variant of cross reinforcement of crossbars in such frames is proposed. The results of a numerical study of the reinforced concrete frame of a multi-storey building with a special impact in the form of an extraordinary hypothetical removal from the work of one of the columns are presented. The modeling of the deformation of the frame is carried out in three versions: the frame of the entire building in the rod setting, a fragment of the building in the column removal zone and a fragment of crossbars adjacent to the column being removed using volumetric finite elements. The obtained results showed the effectiveness of the proposed variant of cross-reinforcement of crossbars to protect a multi-storey frame building from progressive collapse, as well as the effectiveness of using the proposed variant of three-level models for calculating the parameters of static-dynamic deformation of the carcasses of multi-storey buildings under the considered special impacts.
{"title":"Deformation of reinforced concrete frames of multi-storey buildings in extreme conditions under special influences","authors":"V. Kolchunov, O. Bushova","doi":"10.22363/1815-5235-2022-18-4-297-306","DOIUrl":"https://doi.org/10.22363/1815-5235-2022-18-4-297-306","url":null,"abstract":"In order to increase plasticity during destruction along inclined sections and to protect against progressive collapse of reinforced concrete frames of multi-storey buildings, a variant of cross reinforcement of crossbars in such frames is proposed. The results of a numerical study of the reinforced concrete frame of a multi-storey building with a special impact in the form of an extraordinary hypothetical removal from the work of one of the columns are presented. The modeling of the deformation of the frame is carried out in three versions: the frame of the entire building in the rod setting, a fragment of the building in the column removal zone and a fragment of crossbars adjacent to the column being removed using volumetric finite elements. The obtained results showed the effectiveness of the proposed variant of cross-reinforcement of crossbars to protect a multi-storey frame building from progressive collapse, as well as the effectiveness of using the proposed variant of three-level models for calculating the parameters of static-dynamic deformation of the carcasses of multi-storey buildings under the considered special impacts.","PeriodicalId":32610,"journal":{"name":"Structural Mechanics of Engineering Constructions and Buildings","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49378529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-28DOI: 10.22363/1815-5235-2022-18-3-255-268
S. Krivoshapko
It was ascertained that investigations on classification of architectural styles for shells and shell structures are absent. Only one published paper is available where architectural styles with indication of dates of appearance of the styles and dates of attenuation of their application are presented and the names of their founders are given. Now, the interest for the design, analysis, and building of thin-walled shells and shell structures is rising. There are no countries without erected shell structures. Hence, it is necessary to make more exact the classification of these erections and the distribution of them into groups. An aim of this work is collection of information about all known architectural styles as applied to shells and shell structures, and grouping of them due to characteristic traits and indications. All architectural styles were divided into five groups, i.e. avant-gardism, art deco style, modernism, ecotech style, and the newest styles. A special scheme, where distribution of architectural styles on these groups is applied to the examined structures, is given. Mutual influence of styles was revealed and presence of architectural directions and style flows in several styles was shown. The conclusions presented in this paper can demand the future accurate definitions and developments because specialists do not have common views to the list of architectural styles and to their classifications.
{"title":"On the basic architectural styles, directions, and style flows for shells and shell structures","authors":"S. Krivoshapko","doi":"10.22363/1815-5235-2022-18-3-255-268","DOIUrl":"https://doi.org/10.22363/1815-5235-2022-18-3-255-268","url":null,"abstract":"It was ascertained that investigations on classification of architectural styles for shells and shell structures are absent. Only one published paper is available where architectural styles with indication of dates of appearance of the styles and dates of attenuation of their application are presented and the names of their founders are given. Now, the interest for the design, analysis, and building of thin-walled shells and shell structures is rising. There are no countries without erected shell structures. Hence, it is necessary to make more exact the classification of these erections and the distribution of them into groups. An aim of this work is collection of information about all known architectural styles as applied to shells and shell structures, and grouping of them due to characteristic traits and indications. All architectural styles were divided into five groups, i.e. avant-gardism, art deco style, modernism, ecotech style, and the newest styles. A special scheme, where distribution of architectural styles on these groups is applied to the examined structures, is given. Mutual influence of styles was revealed and presence of architectural directions and style flows in several styles was shown. The conclusions presented in this paper can demand the future accurate definitions and developments because specialists do not have common views to the list of architectural styles and to their classifications.","PeriodicalId":32610,"journal":{"name":"Structural Mechanics of Engineering Constructions and Buildings","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41822363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}