Home Vestnik MGSU Library Vestnik MGSU 2018/9

Vestnik MGSU 2018/9

DOI : 10.22227/1997-0935.2018.9

Articles count - 12

Pages - 1164

Current revision of the fundamental Eurocode for design of civil engineering structures

  • Marková Jana - Klokner Institute, Czech Technical University (CTU), in Prague, 7 Šolínova, Prague 6, 166 08, Czech Republic ssociated Professor; ORCID ID 0000-0002-9674-0718, Klokner Institute, Czech Technical University (CTU), in Prague, 7 Šolínova, Prague 6, 166 08, Czech Republic, 7 Šolínova, Prague 6, 166 08, Czech Republic.
  • Holický Milan - Klokner Institute, Czech Technical University (CTU), in Prague, 7 Šolínova, Prague 6, 166 08, Czech Republic Professor; ORCID ID 0000-0001-5325-6470, Klokner Institute, Czech Technical University (CTU), in Prague, 7 Šolínova, Prague 6, 166 08, Czech Republic, 7 Šolínova, Prague 6, 166 08, Czech Republic.
  • Sýkora Miroslav - Klokner Institute, Czech Technical University (CTU), in Prague, 7 Šolínova, Prague 6, 166 08, Czech Republic Associated Professor; ORCID ID 0000-0001-9346-3204., Klokner Institute, Czech Technical University (CTU), in Prague, 7 Šolínova, Prague 6, 166 08, Czech Republic, 7 Šolínova, Prague 6, 166 08, Czech Republic.

Pages 1036-1042

The present, globally-applicable revision of the fundamental EN 1990 Eurocode for the design of buildings and civil engineering structures is briefly summarised. General requirements are further elaborated with respect to structural resistance, serviceability and durability. In addition, provisions for robustness, sustainability and fire safety are included. An appropriate level of structural reliability should consider the consequences and possible causes of failure, public aversion and costs associated with reducing the risk of failure. However, the choice concerning the reliability level is left to national interpretation. The target reliability indexes are indicated for one-year and 50-year reference period, with no explicit link to the design working life being provided in the final draft of prEN 1990. It is proposed that the consequences of structural failure be organised into five categories; however, without providing recommendations on the target reliability indices for the lowest and highest consequence class. Supplementary guidance on structural robustness is proposed in prEN 1990, Annex E. A structure should have a sufficient level of robustness that it will not be damaged to an extent disproportional to the original cause. The working life design should be considered for time-dependent performance of the structures. Ultimate and serviceability limit states should be verified for all relevant design situations. Apart from the commonly-used partial factor method, which comprises a basic method for structural verification, additional guidance is also given for application of non-linear methods. The partial factors have been newly-calibrated with the aim of achieving a more balanced reliability level for structures from different materials and loading effects.

DOI: 10.22227/1997-0935.2018.9.1036-1042

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АРХИТЕКТУРА И ГРАДОСТРОИТЕЛЬСТВО. РЕКОНСТРУКЦИЯ И РЕСТАВРАЦИЯ

Aeration modes and engineering preparation of slopes

  • Lifshits Valeria M. - Politecnico di Milano Master of Science in Architecture, Politecnico di Milano, 32 Piazza Leonardo da Vinci, Milano, 20133, Italy.
  • Korobeynikova Anna E. - Moscow Information and Technology University - Moscow Architectural and Construction Institute (MITU-MASI) Senior Lecturer, Moscow Information and Technology University - Moscow Architectural and Construction Institute (MITU-MASI), 1 A Vvedensky st., Moscow, 117342, Russian Federation.
  • Dunichkin Ilya V. - Moscow State University of Civil Engineering (National Research University) (MGSU) Candidate of Technical Sciences, Associate Professor, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.

Pages 1043-1054

Subject: the aeration mode of the sloping territories of different terrain, for which engineering adaptation measures are needed. Objectives: analyze the patterns of airflow over the sloping areas, affecting the bioclimatic comfort and wind erosion of the landscape. Materials and methods: flow patterns of sloping areas with different characteristics are given and an assessment of the bioclimatic comfort for a person is presented. Geotechnical methods are presented in the solution of problems of wind erosion and stability of slopes of hills and complex relief in the city. Results: the relationship between the relief and the aeration regime of the territory, the dependence of the aerodynamic roughness on their height, the features of the aeration of the slope and hilly relief, the factors influencing the direction and speed of the wind and the methods for studying the aeration mode of the sloping territories are considered. The results of complex studies on slope territories and recommendations for improving design solutions are presented. The issue of wind erosion and bioclimatic comfort of the territory on the slope is considered, regardingthe aeration regime. Conclusions: the possibilities of using geotechnical structures for strengthening slopes using biopositive structures that affect the parameters of aeration and bioclimatic comfort of the environment are demonstrated, which increases the health indicators of the population.

DOI: 10.22227/1997-0935.2018.9.1043-1054

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The results of the research of fiber-optical converter of the monitoring system of building constructions

  • Seregin Nikolay G. - Moscow State University of Civil Engineering (National Research University) (MGSU) Сandidate of Тechnical Sciences, Associate Professor of the Department of Architectural and Construction Design, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .
  • Giyazov Botir I. - Moscow State University of Civil Engineering (National Research University) (MGSU) Candidate of Technical Sciences, Associate Professor, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Pages 1055-1066

Subject: the results of research of fiber-optic Converter of monitoring system of technical condition of building structures are considered. The formulation of monitoring of technical condition of building structures is given. The methods and means of measurement for monitoring are named. The work of automated stationary systems, which are designed to detect changes in the stress-strain state of building structures in an automated mode, is described. The wide use automated stations on the basis of fiber-optic measuring systems is shown. Advantages of fiber-optic measuring systems over similar systems are given. A brief description of fiber-optic methods and means of measuring distances and displacements of technical objects in space is given. Materials and methods: the aim of the research is formulated and the tasks for its achievement are set. The list of methods and means of monitoring of building structures is given. The spectral method of low-coherence interferometry was chosen for the study, which consists in measuring the radiation power spectrum with subsequent mathematical processing of this spectrum. A brief description of the spectral method of fiber-optic low-coherence interferometry is given and its advantages are analyzed. The main advantage of the spectral method of fiber-optic low-coherence interferometry is the high accuracy of measurements of physical quantities. The advantages of fiber-optic sensors to achieve this goal over other devices are considered and justified. Results: the design of fiber-optic sensors of temperature and deformation has been developed. Investigated the practical application of fiber-optical sensor operating according to the method of low-coherence spectral interferometry of, for the decision of tasks of monitoring of technical condition of building structures on the example of monitoring of deformation of the fastening element of the building structure in the process of operation technology of manufacturing of fiber-optic sensors. Designs of the fixing devices equipped with fiber-optic sensors are developed. The technique and experimental setup for testing fixing devices equipped with fiber-optic sensors are developed. The results of their tests are presented. Conclusions: based on the results of the work, conclusions and recommendations for further research are formulated. The results of the research have been repeatedly published in various scientific periodicals. The work is intended for complex generalization of earlier achieved results and setting of tasks of further researches. Application of the spectral method of fiber-optic low-coherence interferometry allows to provide not only high accuracy and reliability of measurement of deformations of structural building elements, but also complex construction systems for various purposes in the process of their research, design, manufacture and operation. This makes it possible to recommend the use of fiber-optic converters as sensors in measuring systems for monitoring of building structures.

DOI: 10.22227/1997-0935.2018.9.1055-1066

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The results of the experimental studies of reinforced concrete structures of hydraulic structures with interconnect construction joints, reinforced by external reinforcement of carbon fiber

  • Rubin Oleg D. - Scientific Research Institute of Energy Structures (Open Joint-stock Company) Doctor of technical sciences, General Director, Scientific Research Institute of Energy Structures (Open Joint-stock Company), 7a Construction travel, Moscow, 125362, Russian Federation.
  • Lisichkin Sergey E. - Engineering Center of Structures, Constructions and Technologies in Power Engineering (Limited Liability Company) Doctor of technical sciences, Deputy General Director, Engineering Center of Structures, Constructions and Technologies in Power Engineering (Limited Liability Company), 35 Freedom st., Moscow, 125364, Russian Federation.
  • Frolov Kirill E. - Public Joint-Stock Company Federal Hydro-Generating Company - RusHydro (PJSC «RusHydro») engineer, Deputy Director General of Scientific and Project Activities, Public Joint-Stock Company Federal Hydro-Generating Company - RusHydro (PJSC «RusHydro»), 51 Architect Vlasov st., Moscow, 117393, Russian Federation.

Pages 1067-1079

For the purposes of experimental validation of application of external reinforcement of carbon fiber to reinforce reinforced concrete structures of hydraulic structures the experimental models of typical structures of hydraulic structures with inter-block construction joints were tested. At the same time, beam-type models of concrete of class B15 with a reinforcement percentage of 0.39 % and concrete of class B25 with a reinforcement percentage of 0.83 % were tested for the effect of bending moment. The models of fragments of reinforced concrete structures of hydraulic structures of concrete class B15 with a reinforcement percentage of 0.445 % and concrete B25 with a reinforcement percentage of 0.7 % were tested for сentral extension. Reinforced concrete beam-type models were reinforced with external reinforcement of carbon tapes of the type FibArm 530/300. Models of hydraulic structures fragments were reinforced by external reinforcement from carbon tapes of the type FibArm Tape 530/300 and from carbon composite lamellae of the type FibArm Lamel 12/50. The reinforced concrete beam-type models were reinforced with carbon strips (longitudinal bands on the lower stretched face and transverse belts in the span and supporting zones). The models of fragments of reinforced concrete structures of hydraulic structures were reinforced with carbon strips and carbon composite slats directed along the action of longitudinal tensile force. The results of experimental studies showed a significant increase in the strength of reinforced concrete structures of hydraulic structures due to their reinforcement by external reinforcement of carbon fiber, and also revealed a special character of the crack formation due to the presence of inter-block construction joints. Subject of the research: the subject of the study: reinforced concrete structures of hydraulic structures (with interblock construction joints), reinforced with external reinforcement of carbon fiber. Materials and methods: reinforced concrete models were made from ordinary heavy-weight concrete of classes B15 and B25 and reinforcement of A500C class. The outer reinforcement was made of carbon tapes of the type FibArm Tape 530/300 and FibArm Lamel12 / 50. Experimental studies were carried out on the basis of physical modeling of characteristic reinforced concrete structures of hydraulic structures with interblock building joints. In this model, the beam type of concrete class B15 with a percentage of reinforcement of 0.39 % and of concrete class B25 with a percentage of reinforcement 0.83 % were tested for the action of bending moment. Models of fragments of reinforced concrete structures of hydraulic structures from concrete class B15 with a reinforcement percentage of 0.445 % and of concrete B25 with a reinforcement percentage of 0.7 % were tested for the effect of central stretching. Experimental models were equipped with control and measuring equipment for determining the values of deflections, deformations of concrete and reinforcement elements of models, crack opening width and interblock joints. Results: in the course of experimental studies, a significant increase in the strength of reinforced concrete structures of the hydraulic structures (in 1.47-2.34 times) was obtained under the action of the bending moment and the central extension due to their reinforcement by external reinforcement from the carbon fiber. Conclusions: based on the obtained experimental data on the significant increase in the strength of reinforced concrete structures of hydraulic structures (by 1.47-2.34 times) due to reinforcement by carbon composite tapes and carbon composite lamella, the substantiation of the use of external reinforcement from carbon bands and lamellas under the action of a bending moment and central extension. Also, a special type of cracking was observed, due to the presence of interblock joints, the study of which allows controlling the implementation of technical solutions for reinforcing, repairing, reconstructing reinforced concrete structures of hydraulic structures.

DOI: 10.22227/1997-0935.2018.9.1067-1079

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Stress-strain state of the seam with zigzag geosynthetic diaphragm

  • Sainov Mikhail P. - Moscow State University of Civil Engineering (National Research University) (MGSU) Candidate of Technical Sciences, associate professor of the Department of hydraulic and hydraulic construction, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .
  • Zverev Andrey O. - Moscow State University of Civil Engineering (National Research University) (MGSU) postgraduate, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.
  • Sklyadnev Mikhail K. - Moscow State University of Civil Engineering (National Research University) (MGSU) student, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.

Pages 1080-1089

Subject: despite the accumulated experience in the construction of ground dams with anti-filtration elements from geosynthetic products, the response of geosynthetic products in the structure of ground dams have been little studied. It was not determined whether positive stretch values can arise in the polymeric anti-filtration elements and whether they can threaten integrity of anti-filtration elements. For this, studies of the stress-strain state are required. The recent results of investigations of the physico-mechanical properties of contacts of polymeric geomembranes with soils allow us to study the behavior of geosynthetic products in the structure of soil dams. One of the possible designs - a high ground seam with a zigzag geosynthetic diaphragm - has been studied here. Materials and methods: investigations of the stress-strain state of the seam were carried out using numerical simulation. Calculations were carried out for a wide range of physico-mechanical properties of the geomembrane and the contact of geomembrane with the soil. The modulus of linear deformation of the polymer material, the angle of internal friction, and the tangent stiffness of the contact were varied. Results: the results of studies of the analyzed seam designs have shown that, in the main, the stresses in the geomembrane are determined by the modulus of linear deformation of the polymer material. The higher the stiffness of geomembranes, the higher are the tensile stresses in them. The shear characteristics of the geomembrane-soil contact are also important. The lower the shear strength of the contact, the higher are the tensile stresses in the geomembrane. Conclusions: the most vulnerable point of the zigzag diaphragm is its upper anchors, because it is in them that the greatest tensile stresses occur. It is recommended to turn them to the bottom side. In the diaphragm of the considered structure, it is impossible to use a geomembrane made of polyethylene; it is necessary to use a geomembrane made of PVC.

DOI: 10.22227/1997-0935.2018.9.1080-1089

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Model engineering scheme of the organization of construction in the future the life cycle of objects

  • Shinkareva Galina N. - Moscow State University of Civil Engineering (National Research University) (MGSU) postgraduate student of the Department of information systems, technologies and automation in construction, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.

Pages 1090-1105

Subject: in the modern realities of socio-political and economic crises for the “survival” of the construction industry is vital to modernization, taking into account modern scientific achievements, rapid development of new technologies and effective methods of production. The creation of prerequisites for the formation of competitive advantages of the construction industry led to the need to develop new schemes of construction organization that increase the efficiency of not only planning, but also the implementation of design solutions in the future life cycle of objects. Materials and methods: methodical tools of the theory of management of technical and production systems, a method of analysis and comparison of organizational structures of investment and construction activity, analysis of theory, practice and ways to improve the efficiency of modern engineering schemes for the organization of construction, methods of logical and semantic and simulation modeling, normative and technical documentation in the study area. Results: interaction of all participants of investment and construction activities in the implementation of life cycle contracts is presented in the log-information model of the engineering design of the construction organization, in which the construction organizer rationally selects options for performing work, taking into account their significance category, the impact of random factors and organizational and technological reliability of the decisions made. Conclusions: the possibility of a complex increase in the efficiency of all stages of planning, designing, erecting the operation and utilization of construction objects (buildings, structures, complexes) based on the use of modern engineering schemes for the organization of construction for lifecycle contracts is substantiated. Ensuring the progressive growth in the demand for integrated engineering services is possible provided that the legislative responsibility of investors, customers or developers is strengthened for the result of its project management that motivates them to engage engineering companies (construction organizers) as a more competent and less costly alternative to the existing capital construction departments, general contracting design and construction companies, audit and control organizations.

DOI: 10.22227/1997-0935.2018.9.1090-1105

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Treatment of external thermal insulation composite systems (ETICS) with bio corrosion with respect to environment protection

  • Antošová Naďa - Slovak University of Technology in Bratislava associate professor of the Department of Building Technology, Slovak University of Technology in Bratislava, 11 Radlinského, Bratislava, 813 68, Slovakia.
  • Minarovičová Katarína - Slovak University of Technology in Bratislava senior lecturer of the Department of Building Constructions, Faculty of Civil Engineering, Slovak University of Technology in Bratislava, 11 Radlinského, Bratislava, 813 68, Slovakia.
  • Belániová Barbora - Slovak University of Technology in Bratislava Postgraduate student of the Department of Building Technology, Faculty of Civil Engineering, Slovak University of Technology in Bratislava, 11 Radlinského, Bratislava, 813 68, Slovakia.

Pages 1106-1111

Subject: the treatment of External Thermal Insulation Composite Systems (ETICS) surfaces affected by bio-corrosion takes place as a part of planned or operational maintenance. As part of this process, ambient environments are loaded with running water and detergents that contain heavy metals. The article presents the results of research on reducing the impact of environmental contamination by cleaning and preventive coating of ETICS surfaces with biocides. The paper gives an overview of the problem and new approaches to the treatment of new and renovated buildings. Purposes: at the present time, the maintenance of existing ETICS lacks system solutions, instead using chemical methods for the treatment of contamination by microorganisms. While complete information on environmental impacts is lacking it is necessary to take this into consideration. The cost of renovation, which should include investment for future treatment of ETICS surfaces, is often underestimated. Film preservation biocides contain both algaecides and fungicides. Consequently, ETICS preservation agents in exterior paints and renders represent a potential risk for humans, animals and the wider biological environment and new concepts underlying more sustainable approaches are required. Materials and methods: the research was based on an evaluation of existing technologies for eliminating microorganisms from the ETICS surfaces and an analysis of their environmental effects. The aim was to find optimal operational and planned ETICS maintenance approaches that minimise negative environmental effects. Results: environmentally-friendly approaches were identified and a new leaching system for safe dewatering was designed. These approaches differ according to their suitability for periodic or operational maintenance. Conclusions: there is a wide range of materials used for ETICS finishes. It is important to consider the reliability and maintainability of the construction across the entire life cycle of a building. Operation and maintenance should be a significant element of the life-cycle cost of a building. The removal of bio corrosion coatings from ETICS structures by means of chemical and preservative substances (biocides) is currently the most-used and only effective technology. The uncontrolled release of applied chemicals is unacceptable. A system designed for collecting wastewater from the cleaned surface is considered an effective means of reducing the deleterious effects of biocidal substances on the environment. The safe dewatering of chemicals leached from the surface of the facade is presented by a drain system designed in accordance with the building type, use and age.

DOI: 10.22227/1997-0935.2018.9.1106-1111

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Erosion of the frozen riversides of the northern rivers depending on the direction of the coastal slope

  • Debolsky Vladimir K. - Water problem institute of RAS Head of laboratory of the dynamics of channel flows and ice heat, Water problem institute of RAS, 3 Goubkina st., Moscow, 119333, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .
  • Gritsuk Iliya I. - Water problem institute of RAS Candidate of Technical Sciences, Senior Researcher, assistant professor, Water Problems Institute of RAS (WPI RAS), Water problem institute of RAS, 3 Goubkina st., Moscow, 119333, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .
  • Ionov Dmitry N. - Peoples’ Friendship University of Russia (RUDN University) Candidate of Technical Sciences, junior researcher, Peoples’ Friendship University of Russia (RUDN University), 6 Miklukho-Maklaya st., Moscow, 117198, Russian Federation.
  • Maslikova Oksana J. - Water problem institute of RAS Candidate of Technical Sciences, Water problem institute of RAS, 3 Goubkina st., Moscow, 119333, Russian Federation.

Pages 1112-1124

The problems of hydraulic engineering require expansion of the scale of research on destructive coastal processes of water bodies located on the territory of the permafrost. Subject: of research in this article are the slopes of the rivers located in the zone of frozen rocks, and the main possible processes on them, occurring under the influence of various seasonal factors. The aim of this work is to study the thermo erosion slope processes of permafrost with allowance for hydromechanical and thermodynamic factors and the development of the main characteristics of these processes, as well as the construction of a single model that allows estimating and predicting the effect of seasonal conditions (including spring snowmelt and exposure to solar radiation) on possible destructive coastal processes at water bodies located on the territory of the permafrost zone. Materials and methods: theoretical analysis and generalization of known achievements in the field of hydrology and glaciology, the theory of slope processes, sediment transport, mechanics of frozen soils, and filtration. As a factual material, the data of laboratory experiments carried out in the PFUR hydraulic laboratory on a facility that allows varying rain currents of varying intensity, while measuring both the rate and number of infiltration flows, and the amount of side flow in the case of frozen or partially thawed soil, that were used as factual material. A various soil structure was modeled by freezing or introducing ice interlayers. Such studies in the laboratory were conducted for the first time. Results and conclusions: a method for predicting thermo-erosion is proposed taking into account the effect of seasonal conditions on permafrost. The influence of the direction of the coastal incline on the rate of thawing of soils under the influence of solar radiation is studied. The influence of ultraviolet rays on snow melting is different from the influence of infrared rays, since short waves (UV) penetrate deep into opaque substances and are transformed into heat fluxes within the snow layer. Cloudiness is a deterrent only for the IR portion of the spectrum. It has been shown experimentally that the dependence of the erosion of solid matter on the slope angle (other things being equal) will have a exponent (4/3) form. Thawing and erosion of frozen water bodies are proportional to the square root of time. The linear coefficient depends on the nature of the rock, ice content, ambient temperature and flow temperature. On the basis of the results obtained, it is possible to give practical recommendations for preventing and reducing the negative impact of the destructive processes under investigation, which is especially important for those areas where intensive hydrotechnical construction is being carried out.

DOI: 10.22227/1997-0935.2018.9.1112-1124

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Friction piles behavior in soil base and piles settlement calculation

  • Utkin Vladimir S. - Vologda State University (VSU) Doctor of Technical Scinces, Professor of Department of industrial and civil engineering, the honored worker of the higher school of the Russian Federation, Vologda State University (VSU), 15 Lenina st., Vologda, 160000, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Pages 1125-1132

Subject: friction piles are calculated by the first and second group of limit states. The article describes a new method for friction pile design by the second group (by settlement) of limit state in relation to the pile foundations of buildings and structures in the urban area and in the design of extensions to existing buildings in which the value of settlement is limited or unacceptable. A new method of piles settlement calculation is different from existing method by the Building Code SP 24.13330.2011. The method is based on a new approach of the pile behavior in soil base, which is different from the existing regulations and science papers. Research objectives: the new method of pile settlement calculation is presented with the purpose of clarifying the calculation of pile bearing capacity unlike an existing method in the Building Code (SP 24.13330.2011). The basis of the design is a new idea of the pile behavior in the soil base, which differs from the existing approaches. Materials and methods: the method consists in the formation of the pile settlement only as a result of pile shortening from the compressive force by the deformation of the pile material. Results: the design equation is presented for calculation the pile settlement caused by the pile material deformation. The condition for determining the pile length is presented, which provides the pile settlement only due to the pile material deformation. Conclusion: such approach of the pile settlement calculation is necessary for the design of extensions to existing buildings, as well as new structures near existing buildings, in which the settlement value is already close to the ultimate value of settlement. The article presents the examples of pile settlement calculations obtained by various methods (including the method of the Building Code SP 24.13330.2011) for comparison of the results. The article can be used in the piles design and in the formation of new design standards for pile foundations of structures and machines.

DOI: 10.22227/1997-0935.2018.9.1125-1132

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The influence of grouting contraction joints on the stress-strain state concrete dam during the filling water reservoir of Boguchan HPP

  • Baklykov Igor' Vyacheslavovich - JSC “Institute Hydroproject”, 2 Volokolamskoe shosse, Moscow leading engineer, JSC “Institute Hydroproject”, 2 Volokolamskoe shosse, Moscow, Igor V.

Pages 1133-1142

The monolithic of concrete gravity dams is one of the important features of their construction. As shown by field observations, almost all concrete dams have cracks in one way or another, and the successful operation of gravity dams in the presence of a large number of cracks indicates large reserves of their strength. As a result of the erection of a concrete dam by the method of column cutting, a structural joints is technologically provided for. The static work of the column in this construction scheme is not monolithic, the creation of monolithic concrete columns at the time of filling the reservoir is carried out by cementing these joints and in this case the dam can be considered a massive unified structure. For the best transfer of forces between the columns, as well as the subsequent qualitative unification of the said joints, a so-called keys is made in them. In the present paper, the effect of cementing of joints with keys on the stress-strain state of a concrete dam during the filling of a reservoir is considered. To determine the stress-strain state, the main loads and impacts are taken into account: own weight of concrete, hydrostatic pressure, filtration pressure, and seasonal temperature variation. For calculations, a typical section of the concrete dam of the Boguchanskaya HPP was selected. Analysis of field data for the opening of the joints of the concrete dam at the Boguchanskaya HPP showed that the conducted primary cementing did not fully allow the dam to be made monolithic. Thus, part of the joints, which emerges on the bottom face of the dam, was subjected to alternating temperatures of ambient air with a sufficiently wide amplitude. In connection with this, the periodic nature of the state of the joints appeared, namely, “closing-opening”. Calculations carried out within the framework of this work confirmed the seasonal nature of the joints, which allowed to check the stress-strain state of concrete columns in case of incomplete cementation and to give recommendations on further cementation of joints. Materials and methods: analysis of stress-strain state, finite element method. Results: the behavior of concrete column of a gravity dam is analyzed taking into account the incompleteness monolithic of inter-columnar joints by calculating the non-stationary heat conduction problem with subsequent determination of the stress-strain state of concrete column. Seasonal places of opening of inter-columnar joint were identified and their unevenness in the opening of the seam height was revealed. Conclusions: practical application of the methods used to take into account the real configuration of the fine seams of the performed calculations allows us to more accurately determine the stress-strain state of the concrete columns of the dam, as well as the effect of omonivation on the stress-strain state.

DOI: 10.22227/1997-0935.2018.9.1133-1142

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Research of the environmentally safe waste-based building materials

  • Mymrin Vsevolod A. - Technological Federal University of Parana Professor, Technological Federal University of Parana, Avenida de deputado Heitor Alencar Furtado, 5000, Ecoville, Curitiba, Brasil.
  • Tolmacheva Natalia A. - Irkutsk National Research Technical University (INRTU) senior research scientist, Irkutsk National Research Technical University (INRTU), 83 Lermontova st., Irkutsk, 664074, Russian Federation.
  • Zelinskaya Elena V. - Irkutsk National Research Technical University (INRTU) Professor, Irkutsk National Research Technical University (INRTU), 83 Lermontova st., Irkutsk, 664074, Russian Federation.
  • Kurina Anastasia V. - Irkutsk National Research Technical University (INRTU) post-graduate student аСМ-16-1, Irkutsk National Research Technical University (INRTU), 83 Lermontova st., Irkutsk, 664074, Russian Federation.
  • Garashchenko Aleksandr A. - Irkutsk National Research Technical University (INRTU) master’s student ISTm-18-1, Irkutsk National Research Technical University (INRTU), 83 Lermontova st., Irkutsk, 664074, Russian Federation.

Pages 1143-1153

Introduction: in the article the estimation of new ecological safety biopositive polymer-mineral composite (BPMC) building materials obtained with the use of technogenic wastes is considered. This approach is one of the ways to solve the problem of improving the environmental safety of the environment. Materials and methods: BMPC environmental safety studies were performed using microstructural, X-ray and elemental analysis methods, studying physical and mechanical properties and fire safety. Man-caused wastes inventory and classificational ecological assessment by the lif e cycle was carried out. Results: the conformity of the Baikal region man-caused wastes (such as fly ash from heat-power engineering, aluminosilicate microspheres, isolated from bottom ash wastes, marble dust (microcalcite), industrial waste of polyvinylchloride (PVC), as well as small-sized mica waste in the form of vermiculite) to the basic characteristics that allow to use this wastes in the production of BMPC-products by extrusion as fillers. The man-caused wastes ecological utilization mechanism was developed. Composition of composite materials, in which industrial PVC waste is used as the matrix, and fly ash, ash microspheres, marble dust and vermiculite as fillers, were developed. The proposed technology for the production of BPMC products allows the use of technogenic wastes in a wide range in the composition from 20 to 60 %. The new biopozitive polymer-mineral composite products properties were studied. Conclusions: the conducted studies of the composition and properties of samples obtained using different types of man-made waste in the polymer-mineral composites production proved that the production of BPMC products ensures the building materials and environmental safety through the reliable and durable materials production that comply with regulatory requirements. According to the life cycle environmental safety assessment, the waste products obtained on the basis of waste have significant advantages in terms of a technical and environmental characteristics set.

DOI: 10.22227/1997-0935.2018.9.1143-1153

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Determination of buildings sun shields operating parameters for the purpose of durability and sustainability

  • Yang Hui - Beijing University of Civil Engineering and Architecture Ph.D, Associate Professor, Beijing University of Civil Engineering and Architecture, Zhanlanlu, 100044, Xicheng District, Beijing, P.R. China; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .
  • Lushin Kirill I. - Moscow State University of Civil Engineering (National Research University) (MGSU) , Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.
  • Plushenko Natalia Yu. - Moscow State University of Civil Engineering (National Research University) (MGSU) , Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.

Pages 1154-1164

Considers the modern building envelope construction with outside skin used as a sun shields. Such a constriction is often used for buildings with low energy consumption. A number of factors besides sun radiation influencing on the performance of facade system in general and every certain parts and elements throughout the entire period of building operation. Subject: multilayer and double skin building facades and sun screens located on their surfaces. Including, dual-use facades combining functions of the sun screen and sub construction for the placement of photovoltaic cells. Materials and methods: the main method was an estimation the aerodynamic and air-thermal characteristics of a double skin façade. Was considered a construction with combined function of a sun shield. The method was previously used in evaluation of the air-thermal regime of hinged facade systems of buildings for cold period of a year. The general approach was advanced and verified by the results of full-scale tests of building facades in the warm period of the year. Results: indicates great influence of air and thermal conditions of air gap in double skin and similar construction facades on performance of façade system in general and on every certain part of it. Conclusions: the construction of complex facade systems with the use of up to date technologies requires additional study of the air-thermal conditions of the air gap between the main facade of the building and its second skin or sun screen. Ignoring the operational features of active sun shields under extreme loads can lead to a decrease in the equipment functionality and its premature failure.

DOI: 10.22227/1997-0935.2018.9.1154-1164

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