{"title":"DETERMINATION OF RHEOLOGICAL PARAMETERS OF POLYMERIC MATERIALS USING NONLINEAR OPTIMIZATION METHODS","authors":"S. Yazyev, A. Chepurnenko, S. Litvinov","doi":"10.34031/2618-7183-2020-3-5-15-23","DOIUrl":"https://doi.org/10.34031/2618-7183-2020-3-5-15-23","url":null,"abstract":"The article is devoted to the problem of processing the experimental creep curves of polymers. The task is to determine their rheological characteristics from tests for any of the simplest types of deformation. The basis for the approximation of the experimental curves is the nonlinear Maxwell-Gurevich equation. \u0000The task of finding the rheological parameters of the material is posed as a nonlinear optimization problem. The objective function is the sum of the squared deviations of the experimental values on the creep curve from the theoretical ones. Variable input parameters of the objective function are the initial relaxation viscosity and velocity modulus m*. A theoretical creep curve is constructed numerically using the fourth-order Runge-Kutta method. The nonlinear optimization problem is solved in the Matlab environment using the internal point method. The values m* and are found for which the objective function takes the minimum value. \u0000To test the technique, the inverse problem was solved. For given values of the rheological parameters of the material, a theoretical curve of creep under bending was constructed, and the values m* and were found from it. The technique was also tested on experimental stress relaxation curves of secondary polyvinyl chloride and creep curves of polyurethane foam with a pure shear. \u0000A higher quality approximation of experimental curves is shown in comparison with existing methods. The developed technique allows us to determine the rheological characteristics of materials from tests for bending, central tension (compression), torsion, shear, and it is enough to test only one type of deformation, and not a series, as was suggested earlier by some researchers","PeriodicalId":127090,"journal":{"name":"Construction Materials and Products","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129180121","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}
A. Kozin, R. Fedyuk, Yu. Il'inskiy, S. Yarusova, P. Gordienko, M. A. Mosaberpanah
{"title":"EFFECT OF WOLLASTONITE ON THE MECHANICAL CHARACTERISTICS OF CONCRETE","authors":"A. Kozin, R. Fedyuk, Yu. Il'inskiy, S. Yarusova, P. Gordienko, M. A. Mosaberpanah","doi":"10.34031/2618-7183-2020-3-5-34-42","DOIUrl":"https://doi.org/10.34031/2618-7183-2020-3-5-34-42","url":null,"abstract":"Improvement of the physical and mechanical properties of cement composites should be accompanied by the disposal of industrial waste of various generation. Therefore, the paper proposes the principles of controlling the strength properties of concrete, which consist in the complex effect of wollastonite obtained from boron production waste on the processes of structure formation of the cement matrix. When this introduced in an amount of 2-8 wt. % wollastonite has a dual function as a mineral filler and a reinforcing fiber. It has been proven that in the presence of wollastonite, the concrete mix becomes lighter without reducing its physical and mechanical properties. It was revealed that the early strength for all the developed compositions with the addition of wollastonite increases due to the acceleration of hydration processes. Calcium silicate, which is wollastonite CaSiO3, has a close chemical composition with cement clinker, especially with Ca2SiO4 belite and Ca3SiO5 alite. This leads to the formation of a chemically homogeneous and, as a result, hardened microstructure. Elongated wollastonite fibers with good adhesion to the cement stone provide effective micro-reinforcement of the concrete composite. Using the results will lead to the possibility of designing high-strength concretes, including for special structures","PeriodicalId":127090,"journal":{"name":"Construction Materials and Products","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124088311","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}
V. Krylov, D. Sarkisov, E. Ergeshov, E. Evstaf’eva
{"title":"PROGRAM OF EXPERIMENTAL STUDIES OF THE LOAD-BEARING CAPACITY OF GIRDERLESS PLATES FOR PUSHING UNDER DYNAMIC LOADING. DESIGN OF PROTOTYPES","authors":"V. Krylov, D. Sarkisov, E. Ergeshov, E. Evstaf’eva","doi":"10.34031/2618-7183-2020-3-3-47-53","DOIUrl":"https://doi.org/10.34031/2618-7183-2020-3-3-47-53","url":null,"abstract":"this article presents a program for experimental research of the behavior of reinforced concrete slabs when forced through in static and short-term dynamic loading modes. At hazardous production facilities, there is always an increased probability of emergency situations of disaster nature that lead to explosions and are characterized by a sharp increase in the front, a short duration and a wave character. Taking into account the placement of complex technological processes in buildings, it is now necessary to implement “flexible” space-planning solutions, for example, the use of girderless floors. The need to perform these studies is also due to the lack of methods and regulatory documents that regulate the calculation of the penetration of unbalanced monolithic slabs under dynamic loading. The purpose and objectives of this program are: to assess the influence of the thickness of the slab part of samples and the concrete class on the strength and crack resistance of elements, to obtain new experimental data describing the processes occurring in concrete and reinforcement, to identify patterns of destruction of samples. The test was carried out on a test stand based on a copra rig. The choice of sizes of prototypes is determined by the technical characteristics of this installation, the tasks of the experiment, the possibilities of manufacturing and testing models, and obtaining sufficiently reliable values of the parameters under study during testing. Twelve samples were tested for short-term dynamic loading and four samples for static loading. The following parameters vary: the concrete class (B15 and B20) and the thickness of the slab part of the sample (100 mm and 120 mm). The paper describes the dimensions, reinforcement, concrete classes of the studied samples, the sequence of work in the manufacture of samples, taking into account the installation of load cells. The result of this work is the development of a test method for prototypes.","PeriodicalId":127090,"journal":{"name":"Construction Materials and Products","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129314653","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}
{"title":"DESTRUCTION MODEL OF IDEALIZED CONCRETE STRUCTURE BY SAWING","authors":"A. Varlamov, V. Gavrilov, A. M. Davydova","doi":"10.34031/2618-7183-2020-3-2-46-54","DOIUrl":"https://doi.org/10.34031/2618-7183-2020-3-2-46-54","url":null,"abstract":"the requirements of modern construction are the strength of building structures, as well as low cost. It is these conditions that provide new technologies that are constantly being improved. The article is devoted to the consideration of cases of a probabilistic approach to solving the problem of theoretical energy consumption for the destruction of concrete of ideal structure. \u0000The processes of concrete deformation and its destruction are studied by building mechanics. Concrete is a multicomponent material, which presents a certain difficulty in the study of crack formation. In operating conditions, the concrete/reinforced concrete structure is affected by the properties of its constituent materials; therefore, one of the most important tasks is the selection of criteria that can comprehensively characterize the basic parameters of concrete. Obtaining the strength characteristics of concrete of operated structures remains an urgent task. The article proposes to consider the ideal structure of concrete. The features of this structure are the symmetry of fracture along two principal planes. The destruction of concrete was carried out by sawing individual strips of concrete. Moreover, to describe the sawing process, the authors proposed a model of a symmetric structure of concrete in which aggregate grains are idealized. They are presented in the form of balls in the body of concrete. \u0000The features of the sawing process are revealed. The analytical dependencies of fracture sawing the ideal structure of concrete are obtained. \u0000Conclusions are drawn about the possibility of using the ideal model for obtaining the strength characteristics of concrete. The analysis of symmetrical ideal concrete compositions with various variables is performed. The significance of the work done lies in the possibility of transferring the research results to real buildings and structures and solving the main tasks that are posed in the study","PeriodicalId":127090,"journal":{"name":"Construction Materials and Products","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114381584","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}
{"title":"THE RESEARCH OF MULTILAYER OUTER FENCING INCLUDING MATERIALS USING ASH AND SLAG WASTE OF THERMAL POWER PLANTS","authors":"G. Medvedeva","doi":"10.34031/2618-7183-2020-3-2-29-35","DOIUrl":"https://doi.org/10.34031/2618-7183-2020-3-2-29-35","url":null,"abstract":"the most important direction of resource saving in construction is the widespread use of secondary material resources, which are waste products. The use of secondary products of industry as raw materials for the production of various building materials is very important, because it provides production with rich sources of cheap and, often, already prepared raw materials; lead to lower costs for the production of some building materials, and therefore saves capital investments intended for the construction of buildings and structures; release large areas of land and reduce the impact on the environment. The article deals with heat-insulating and structural-heat-insulating materials, with partial replacement of components by ash-slag waste (ASW): lightweight concretes with broken glass and concretes modified with sulfur. Properties of concretes modified with sulfur are investigated: compressive strength, density and thermal conductivity. In accordance with the obtained properties, a comparative characteristics of the received materials with existing building materials was carried out: sulfur modified concrete and lightweight concrete; lightweight concrete using broken glass and claydite-concrete. Thermophysical calculation of multilayer hencing is made. In each of the options, one of the following materials was selected as a structural and heat-insulating material: lightweight concrete using broken glass and sulfur modified concrete. Also, for each type of hencing, the necessary heat-insulating and structural materials were selected. In the economic part, the cost of the raw materials necessary to obtain 1 m3 of the investigated materials and the cost of 1 m3 of multilayer hencing, which includes the investigated concrete, are calculated.","PeriodicalId":127090,"journal":{"name":"Construction Materials and Products","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123627188","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}
{"title":"INFLUENCE OF ARTIFICIAL CALCIUM HYDROSILICATES ON THE HARDENING PROCESSES AND PROPERTIES OF NON-AUTOCLAVE SILICATE MATERIALS BASED ON UNCONVENTIONAL ALUMINOSILICATE RAW MATERIALS","authors":"A. Volodchenko","doi":"10.34031/2618-7183-2020-3-2-19-28","DOIUrl":"https://doi.org/10.34031/2618-7183-2020-3-2-19-28","url":null,"abstract":"one of the possible ways to improve the properties of building materials is to modify the processes of structure formation, which can be realized through the use of crystalline primers. In this regard, it is urgent to study the effect of artificial calcium hydrosilicates on hardening processes, as well as the properties of non-autoclave silicate materials based on non-traditional aluminosilicate raw materials. Studies have shown that the addition of artificial calcium hydrosilicates (CSH) in an amount of 1-1.5 wt. %, when the content in the mixture of CaO is less than 10 wt. %, effectively increases the strength parameters of products at all stages of heat and moisture treatment from 8 to 16%. The most intense increase in strength is observed during the heat-moisture treatment (TBO) from 3 to 6 hours and is at least 13%, while in samples without the addition of artificial calcium hydrosilicates, the strength increase is 6%. The addition of artificial calcium hydrosilicates intensifies the processes of structure formation, which ensures an increase in crystalline matter, and, due to the fibrous structure, acts as a fiber, which contributes to the nano-reinforcement of the cementing substance formed from neoplasms in the CaO-SiO2(Al2O3)-H2O system based on clay rocks and calcium oxide. Due to the accelerated set of strength, it is possible to reduce the duration of isothermal exposure while maintaining the necessary performance characteristics.","PeriodicalId":127090,"journal":{"name":"Construction Materials and Products","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128084558","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}
{"title":"CALCULATION OF HIGH-RISE BUILDINGS UNDER SEISMIC EFFECT OF “CONTROLLING EARTHQUAKE” LEVEL BY NONLINEAR STATIC METHOD ON THE EXAMPLE OF ADYGHE WIND POWER PLANT","authors":"L. Mailyan, M. Zubrickiy, O. Ushakov, L. Sabitov","doi":"10.34031/2618-7183-2020-3-1-14-20","DOIUrl":"https://doi.org/10.34031/2618-7183-2020-3-1-14-20","url":null,"abstract":"the aim of this work is to test a multi-modal nonlinear static method for seismic impact of the \"controlling earthquake\" level for high-rise structures on the example of a wind power plant (WWP) with a capacity of 1.5-2.0 mW of the Adyghe WPP using computer modeling in the LIRA 10.10 PC. Additionally, the results were verified in the PC “Ansys”. The main bearing element of the WWP is a tower-pipe with a weak taper, the material of which is high-strength steel S355. The assessment of the structure seismic resistance is performed in physically and geometrically nonlinear settings. At the same time, the Vaughn-Mises strength theory was used for steel. Comparison of the calculation results proves the effectiveness of the multi-modal nonlinear static method. The method under consideration has a number of advantages: tolerance to the initial data in terms of numerical description of the seismic impact, less machine capacity of the calculation in comparison with the direct dynamic method, and the ability to automate the calculation process fully.","PeriodicalId":127090,"journal":{"name":"Construction Materials and Products","volume":" 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113948217","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}
{"title":"DIAGNOSTICS OF THE TECHNICAL CONDITION OF THE HISTORICAL BUILDING AT THE ADDRESS: MOSCOW, 2ND VOLKONSKY LANE, 5, P. 1.","authors":"V. ZHelninskiy","doi":"10.34031/2618-7183-2020-3-1-104-110","DOIUrl":"https://doi.org/10.34031/2618-7183-2020-3-1-104-110","url":null,"abstract":"this article discusses the restoration of a historical building, which is an extremely responsible and important work to preserve the valuable Fund of historical buildings in Moscow. With the participation of the author, the work was performed to diagnose the technical condition of the historical building and develop technical solutions for restoring structural elements of the building that have lost their original properties. A set of measures to determine and evaluate the actual values of controlled parameters that characterize the performance of the object of inspection and determine the possibility of its further operation, reconstruction or the need to restore, strengthen, repair, and includes a survey of the soil base and building structures to identify changes in soil properties, deformation damage, defects of load-bearing structures and determine their actual load-bearing capacity","PeriodicalId":127090,"journal":{"name":"Construction Materials and Products","volume":"210 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132239466","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}
{"title":"FINE-GRAINED HIGH-STRENGTH CONCRETE","authors":"A. Tolstoy","doi":"10.34031/2618-7183-2020-3-1-39-43","DOIUrl":"https://doi.org/10.34031/2618-7183-2020-3-1-39-43","url":null,"abstract":"the article discusses the possibilities of improving the strength characteristics of fine-grained concrete. Modification of compositions and production technology of fine-grained high-strength concrete is possible with the use of natural and man-made raw materials of various chemical and mineral composition. It is shown that it is possible to increase the economic feasibility of high-strength fine-grained concretes with the preservation of performance characteristics due to the use of man-made raw materials and production waste. The issues of controlling the processes of structure formation and identifying a potentially stable state of hardening compositions are considered, possibly on the basis of modification and design methods for the composition of construction objects with improved properties.","PeriodicalId":127090,"journal":{"name":"Construction Materials and Products","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117101793","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}
V. Strokova, V. Babaev, I. Markova, K. Sobolev, V. Nelyubova
{"title":"COMPARATIVE EVALUATION OF ROAD PAVEMENT STRUCTURES USING CEMENT CONCRETE","authors":"V. Strokova, V. Babaev, I. Markova, K. Sobolev, V. Nelyubova","doi":"10.34031/2618-7183-2019-2-4-56-63","DOIUrl":"https://doi.org/10.34031/2618-7183-2019-2-4-56-63","url":null,"abstract":"the results of studies on the use of modified basalt fiber reinforced cement concrete coating in the design of hard pavement are presented. It is shown that the use of fiber cement concrete in road structures allows to reduce the thickness of the coating, while having a margin of safety in the concrete layer, and the frame of micro-reinforcing components allows to reduce penetrating loads.","PeriodicalId":127090,"journal":{"name":"Construction Materials and Products","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115655536","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}