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Vestnik MGSU 2018/12

DOI : 10.22227/1997-0935.2018.12

Articles count - 10

Pages - 1555

ARCHITECTURE AND URBAN PLANNING.RECONSTRUCTION AND REFURBISHMENT

The use of porous pavements in creating the infrastructure of the urban environment

  • Dergunova Anna V. - National Research Ogarev Mordovia State University (MRSU) Candidate of Technical Sciences, Associate Professor, Associate Professor of Department of Construction Materials and Technologies, National Research Ogarev Mordovia State University (MRSU), 68 Bolshevistskaya st., Saransk, 430005, Russian Federation.
  • Piksaykina Anna A. - National Research Ogarev Mordovia State University (MRSU) Candidate of Economic Sciences, Associate Professor, Associate Professor of Department of Construction Materials and Technologies, National Research Ogarev Mordovia State University (MRSU), 68 Bolshevistskaya st., Saransk, 430005, Russian Federation.

Pages 1440-1447

Introduction. Considered green construction, which is carried out in accordance with the environmental expediency. A list of environmental problems associated with the impermeability of soil covering cities is given and measures are proposed to eliminate the negative effects of human activity on the environment. Materials and methods. Researched the use of porous pavements, as a means of combating environmental problems and creating a favorable urban environment. The definition of a porous pavement and its difference from the usual road surface is given. A description is given of the component parts of the paving system, including the base, filter cloth, filler tank and porous surface layer. The main types of porous coatings, such as porous concrete, porous asphalt and paving stones are analyzed. It is considered the environmental, aesthetic and economic benefits of porous pavements: replenishing the groundwater supply, combating floods as a result of reducing the volume of storm water, preserving plants in the urban environment, controlling the urban heat regime, cooling the surface waters of rivers and other water bodies, improving traffic safety, monitoring noise. Results. It is presented situations in which the use of porous pavements is not effective. These are, for example, highways with heavy traffic, steep slopes, areas with erosion and soil erosion, roads where chemical reagents are actively used to control ice in the winter, places of likely spills of harmful substances. It is noted that in order to effectively use porous pavements, they must be properly maintained depending on the type of porous pavement. Recommendations on the use of porous pavements are given. Conclusions. Due to their peculiarities, porous pavements cannot be applied everywhere, but this option of pavements should be considered by all capital construction participants interested in introducing green building technologies in our country.

DOI: 10.22227/1997-0935.2018.12.1440-1447

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FOUNDATION AND SUBSTRUCTURE ENGINEERING. SOIL MECHANICS

Development of nondestructive techniques of preliminary soil foundations geotechnical assessment

  • Antipov Vadim V. - Perm National Research Polytechnic University (PNRPU) postgraduate student of Department of Construction Technology and Geotechnics, Perm National Research Polytechnic University (PNRPU), 29 Komsomolsky prospekt, Perm, 614990, Russian Federation.
  • Ofrikhter Vadim G. - Perm National Research Polytechnic University (PNRPU) Doctor of Technical Sciences, Associate Professor, Professor of Department of the construction operations and geotechnics, Perm National Research Polytechnic University (PNRPU), 29 Komsomolsky prospekt, Perm, 614990, Russian Federation.

Pages 1448-1473

Introduction. Modern nondestructive techniques of wave analysis can be applied for the rapid preliminary geotechnical soil assessment. One of these techniques is Multichannel Analysis of Surface Waves (MASW) which allows to obtain velocities profile of shear waves and an initial shear modulus for upper section at minimal duration and labor costs. But for soil deformation properties assessment it is required a deformation modulus obtained by means of direct technique of plate load test. The purpose of the performed study is assessment of the correlation between plate load test deformation modulus and initial shear modulus obtained via wave analysis. Materials and methods. Plate load tests were carried out for various plates and moduli of deformation were calculated. Deformation modulus adjustment factors were applied to perform a comparative analysis of different sizes plates at 5000 cm2 plate. Wave analysis was carried out by the active method of MASW. Results. During comparative analysis a correlation coefficient was evaluated for two cases: the deformation modulus was determined strictly according to GOST 20276-2012; deformation modulus was determined for the loading interval 0.050-0.125 MPa. In the first case “correlation coefficient-unit weight” indicative dependence was observed. The regression equations for the both cases was presented. Conclusions. Correlation between two types of tests was performed by results of in-situ tests. The proposed empirical regression equation allows to obtain the value of the deformation modulus on the basis of wave analysis data and to perform rapidly a soil foundation geotechnical assessment for the future construction.

DOI: 10.22227/1997-0935.2018.12.1448-1473

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ENGINEERING AND STRUCTURAL SURVEY. SPECIAL-PURPOSE CONSTRUCTION

A model of organization life cycle of a medical building

  • Dorogan Igor A. - Almaz-SP Director for construction, Almaz-SP, 7 Obraztsova st., Moscow, 127025, Russian Federation.

Pages 1474-1481

Introduction. An approach to the development of the organizational-technological model of the life cycle of a medical facility building is presented. Buildings of medical organizations have a number of features in the design, construction and operation. The buildings of nuclear medicine are subject to particularly high requirements of radiation and fire safety. Materials and methods. To organize the design, construction and maintenance of medical buildings, it is advisable to create and develop an organizational and technological model of the medical building life cycle. Such model was created by the author in the form of a business processes sequence. Confirmation of the effectiveness of the model is carried out with the help of multi-criteria expert evaluation. Results. To solve this problem, it is proposed a number of changes in the order of the investment project carrying. A new element is the Preliminary justification of the requirements for the health facility. It should become a mandatory document when obtaining a town-planning plan of the ground area, which is in Russia a de facto permission to design. It is also proposed to prepare technical requirements of three levels. The first level requirements are used for pre-design stage procedures. The requirements of the second level are included in the medical and technical design assignment. The requirements of the third level are applied to the detailed design, as well as to the construction and maintenance of the facility. Requirements are included in the requirement system and must be checked at key stages of the project. At the preliminary project phase, it is also advisable to make a technical and economic calculation with the justification of the main technical solutions and technical and economic indicators. This document should also include a project management plan. New elements are included in organizational and technological models of different stages of the object life cycle. Conclusions. On the basis of the developed model, it is proposed to make adjustments to the normative guideline used in the construction management. For example, it is necessary to make mandatory documents of the pre-design stage. These works have to be paid by investor therefore the standard of design cost has to be increased.

DOI: 10.22227/1997-0935.2018.12.1474-1481

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Construction Process Technology. Construction Economics, Administration and Management

Organization and implementation of risk-management in building enterprise

  • Barkhi Reza - Pamplin Hall, Suite 3007, Blacksburg, VA 24061, USA KPMG Professor, Dr., Professor of Pamplin college of business accounting and information systems, Pamplin Hall, Suite 3007, Blacksburg, VA 24061, USA, ; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .
  • Borkovskaya Victoria G. - Moscow State University of Civil Engineering (National Research University) (MGSU) PhD in Economic Science, Associated Professor of Department Housing & Communal Service, 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 1482-1490

Introduction. Consider the system of organization and implementation of risk management in the building enterprise. The introduction and management of risks in an industrial enterprise is an actual problem due to the occurrence of the following list of factors: incomplete information, elements of randomness, unpredictability of actions of a partner or competitor, among others. Risk management is a process that must begin at the development stage of a industrial company’s strategy, and necessarily with the participation of its owners, since it is the owners who, when developing a strategy, should determine the maximum level of total risk that the industry company will be ready to accept in the course of its activities. Risk management in industrial enterprises should be implemented within the framework of the system and process approaches, taking into account the specifics of the industry using modern effective management methods and production organizations, as well as using risk management tools. Materials and methods. The methodology of the continuous risk management process was used to study the industry organization and implementation of risk management, and systems analysis, modeling and synthesis methods were used. Results. It was determined that the creation of a risk management department is appropriate for effective risk management at the industry enterprise. The main responsibilities of this unit, including for staff and other users (including employees, consultants and contractors), in order to successfully implement the management strategy, require unconditional implementation to minimize risks and eliminate costs in implementing risk management. It was revealed that as a result of introducing risk management in industry enterprises of various industries, a set of measures should be developed to evaluate the operational risks of an enterprise, integral risk, quantitative assessment of which is based on a comprehensive analysis of financial and accounting reports, and conducting an integrated risk assessment based on all levels of responsibility within the industrial enterprise. Conclusions. Risk management at industrial enterprises should be carried out within the framework of the system and process approaches, taking into account the specifics of the industry using modern effective management methods and production industrial organizations, as well as using risk management tools.

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Construction Material Engineering

Modifying epoxy polymers by cyclic carbonates of epoxidated plant oils

  • Gotlib Еlena M - Kazan National Research Technological University (KNRTU) Doctor of Engineering, Professor, Professor of the chair of artificial rubber technology, Kazan National Research Technological University (KNRTU), 68 Karl Marx st., Kazan, 420015, Russian Federation.
  • Anh Nguyen - Kazan National Research Technological University (KNRTU) postgraduate student of the chair of artificial rubber technology, Kazan National Research Technological University (KNRTU), 68 Karl Marx st., Kazan, 420015, Russian Federation.
  • Sokolova Аlla G. - Moscow State University of Civil Engineering (National Research University) (MGSU) Candidate of Technical Sciences, Associate Professor, Associate Professor of foreign languages and professional languages Department, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.

Pages 1491-1498

Introduction. Application of renewable raw materials for manufacturing non-toxic components of polymer materials is of great practical interest. Cyclic carbonates on the base of epoxidated rubber tree oil could be seen as a promising alternative of fossil fuels. The ability of compounds containing cyclic carbonates to interact with primary amines and to form urethane and hydroxyl groups makes them rather efficient modifiers of amine-toughened epoxy compounds on the base of low-molecular diane oligomers. Introduction of cyclic carbonates enhances impact behavior of epoxy materials as well as their adhesion and strength properties. Materials and methods. Epoxy resin ED-20 was used for the research, as a cross-linking agent for cold toughening aminealkylphenol AF-2 was used; cyclic carbonates of epoxidated soy oils and rubber tree oil were applied as modifiers. Adhesional strength of bond joints has been determined in compliance with the GOST 28840-90, abrasive hardness of epoxy compound samples has been tested by the vertical optical caliper IZV-1. Results. When applying two-stage technology for obtaining epoxy cyclic carbonate compounds, there has been appeared a significant increase of adhesion to aluminum. This effect could be even more noticeable with increasing temperature during the stage of mixture of the amine toughener with the cyclic carbonate modifier. High viscosity of cyclic carbonate modifiers complicates the process of mixing components of the epoxy compound and correspondingly its application as a backing of glues and linings. The authors researched cyclic carbonates of epoxidated soy oil with various averaged functionality as modifiers. Application of epoxy materials CESO-75 as a modifier has proven to be more forward-thinking for the reasons of cost-efficiency and for operating and technological properties. CESO lowers the coefficient of static friction for epoxy materials together with enhancing their abrasion hardness. Conclusions. Cyclic carbonates of epoxidated plant oils (soy oil and rubber tree oil) as rather efficient non-toxic modifiers of epoxy polymers are of practical interest. They are produced on the base of annually renewable plant raw materials. Their application enables to enhance abrasion hardness and adhesion properties of epoxy compounds and also improve their antifriction properties.

DOI: 10.22227/1997-0935.2018.12.1491-1498

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EFINITION OF DEFORMATION OF FINE-GRAINED CONCRETE ON THE BASIS OF SULPHATE-RESISTANT PORTLAND CEMENT

  • Ngo Xuan Hung - Moscow State University of Civil Engineering (National Research University) (MGSU) postgraduate student of Department of Technology of Binders and Concretes, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.
  • Tang Van Lam - Moscow State University of Civil Engineering (National Research University) (MGSU) postgraduate student of Department of Technology of Binders and Concretes, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.
  • Bulgakov Boris I. - Moscow State University of Civil Engineering (National Research University) (MGSU) Candidate of Technical Sciences, Associate Professor, Associate Professor of Department of Technology of Binders and Concretes, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.
  • Aleksandrova Olga V. - Moscow State University of Civil Engineering (National Research University) (MGSU) Candidate of Technical Sciences, Associate Professor, Associate Professor of Department of Technology of Binders and Concretes, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.
  • Larsen Oksana A. - Moscow State University of Civil Engineering (National Research University) (MGSU) Candidate of Technical Sciences, Associate Professor, Associate Professor of Department of Technology of Binders and Concretes, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.

Pages 1499-1508

Introduction. The possibility of determining the relative deformations of fine-grained concretes based on sulfate-resistant cement was formulated by testing samples of gypsum-cement-sand mixture in distilled water in accordance with the requirements of the Vietnamese standard TCVN 6068:2004. Objective - to determine the deformations of fine-grained concrete because of sulfate-resistant Portland cement in accordance with the requirements of the TCVN 6068:2004 standard to assess its resistance to corrosion in an aggressive sulfate medium. Materials and methods. To obtain a gypsum-cement-sand mixture, a finely disintegrating binder was used, consisting of sulfate-resistant Portland cement of the type CEM I CC 42.5 N produced by the “Tam Diep” plant with the addition of natural gypsum produced by the company “Dinh Vu”. Quartz sand was used as fine aggregate. All raw materials used were native to Vietnam. Grinding fineness, normal cement density, setting time, the uniformity of the volume change and the activity of sulfate-resistant Portland cement were determined according to GOST 30744-2001; deformations of samples from gypsum-cement-sand mixtures - according to the Vietnamese standard TCVN 6068:2004. Results. Investigated the relative increase in the volume of samples of gypsum-cement-sand mixture based on sulfate-resistant Portland cement and natural gypsum as a result of their testing in distilled water according to the standard TCVN 6068:2004. Conclusions. Found that the average value of the relative deformation of the prism samples of concrete as a result of a 14-day test in distilled water was 0.037 %, which is within the acceptable value of 0.04 % in accordance with the requirements of the Vietnamese standard TCVN 6067:2004. Therefore, sulfate-resistant Portland cement type CEM I CC 42.5 N produced by the “Tam Diep” plant is a promising material as a binder for the preparation of corrosion-resistant concrete. The increase in the mean values of the relative deformations of the gypsum-cement-sand prism specimens after the 28-day and 60-day of testing, compared to the results of the 14-day test, can be explained by a slightly increased content of tricalcium aluminate in the studied cement.

DOI: 10.22227/1997-0935.2018.12.1499-1508

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Stress-strain state of fiberglass in conditions of climatic aging

  • Martynov Gleb V. - Peter the Great St. Petersburg Polytechnic University (SPbPU) undergraduate student, Peter the Great St. Petersburg Polytechnic University (SPbPU), 29 Polytechnicheskaya st., St. Petersburg, 195251, Russian Federation.
  • Monastyreva Daria E. - Peter the Great St. Petersburg Polytechnic University (SPbPU) undergraduate student, Peter the Great St. Petersburg Polytechnic University (SPbPU), 29 Polytechnicheskaya st., St. Petersburg, 195251, Russian Federation.
  • Morina Elena A. - Peter the Great St. Petersburg Polytechnic University (SPbPU) undergraduate student, Peter the Great St. Petersburg Polytechnic University (SPbPU), 29 Polytechnicheskaya st., St. Petersburg, 195251, Russian Federation.
  • Makarov Aleksey I. - Peter the Great St. Petersburg Polytechnic University (SPbPU) undergraduate student, Peter the Great St. Petersburg Polytechnic University (SPbPU), 29 Polytechnicheskaya st., St. Petersburg, 195251, Russian Federation.

Pages 1509-1523

Introduction. Were investigated samples of fiberglass with the aim of its effective use in construction in the long term. Fiberglass is considered one of the most versatile and durable materials among polymer composite materials, however, and it is subject to destruction. It is known that one of the main reasons for reducing the specified characteristics and material properties is operational. At the design stage, it is necessary to determine the most reliable and economical materials used and, accordingly, be sufficiently aware of their strength and durability. Thus, in order to avoid the destruction of the material, as well as significantly enhance and prolong its service life, it is necessary to be aware of how exactly the properties of the material change over time. Regarding reinforced concrete, wood, brick and steel fiberglass is used in construction recently. This means that while the service life of the list of the most common materials in construction is known to a sufficient extent, manufacturers do not dare to use fiberglass as a material for critical structures. This occurs because changes in its characteristics, depending on operational factors, are not sufficiently studied for intervals exceeding 4-5 years of operation. Materials and methods. During the work, samples of fiberglass SPPS with a longitudinal and transverse arrangement of fiberglass were tested for climatic aging in a climatic chamber for 5 cycles simulating 5 years of material operation. All samples were subjected to tensile testing on a tensile testing machine R-5. Results. Destructive stresses were determined, calculations were carried out and elastic and strength characteristics of the samples were analyzed. On the basis of the obtained results, an analysis was carried out, conclusions were formulated about the use of fiberglass in the construction in the long term, as well as the influence of such operational factors as moisture, positive and negative temperatures, and ultraviolet radiation on the properties of fiberglass with a different arrangement of fiberglass. Conclusions. Found that the destructive stresses of fiberglass are significantly reduced during the first two years of operation, which must be considered when choosing fiberglass with the stated characteristics. Ultraviolet does not have a significant effect on the elastic-strength properties of the material, while during operat

DOI: 10.22227/1997-0935.2018.12.1509-1523

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Construction System Safety. Environmental Challenges in Construction. Environmental Geology

Fire hazard of phosphorus-containing hard casting polyurethane foams

  • Ushkov Valentin A. - 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.
  • Sokoreva Evgeniya V. - 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.
  • Goryunova Anna V. - 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.
  • Demjanenko Stanislav A. - 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 1524-1532

Introduction. Fire-safe rigid filling polyurethane foams (PUF), meant for low-temperature thermal insulation of pipelines and technological equipment were developed. The effect of concentration of oxyethylated tetraalkylphosphonate pentaerythritol (phostetrol-1) on technological, physico-mechanical and thermal properties, contents of pyrolysis products and main fire hazard indicators of PUFs was explored. The effect of chemical nature and metal compounds concentration of variable valence on fume-generation ability of phosphorous-containing PUFs was examined. Main technological and physico-mechanical properties and fire hazard indicators of developed styrofoams are provided. Materials and methods. Rigid filling PUFs were obtained on the basis of simple oxyethylated polyols and polyisocyanate. Phostetrol-1 was used as a reactive phosphorous-containing compound. As a foaming and hardening catalyst of developed PUF’s a nitrogen-containing polyol (mark Lapromol 294) and dimethylethanolamine was used, and as a foaming agent - mixture of freon - 11 and water. Different metal compounds of variable valence were used to reduce fume-generation ability and toxicity of pyrolysis products of rigid phosphorous-containing PUFs. Thermal properties of examined PUFs were studied with the help of thermoanalytical complex Du PONT 9000. Main technological and physico-mechanical properties and fire hazard indicators of styrofoams were determined under existing GOSTs. Results. The effect of phostetrol-1 concentration in polyester compound on main technological and physico-mechanical properties, contents of pyrolysis products and main fire hazard indicators of rigid filling PUFs was established. It is shown that to obtain moderately flammable PUFs the phosphorous concentration in styrofoam must exceed 2.5 mass. %. The correlation between low-scale evaluation methods of flammability of rigid PUFs was found. The effect of phosphorous concentration on fume-generation ability and contents of pyrolysis products of rigid PUFs was found. The effect of chemical nature and metal compounds concentration of variable valence on fume-generation ability of phosphorous-containing PUFs was examined. It is shown that effective decrease of fume-generation ability and toxicity of pyrolysis products of moderately flammable PUFs occurs when Cu2O or chrome spinels are introduced to the polyester compound. Conclusions. As a result of conducted research it was established that the combined use of phostetrol-1, Cu2O and chrome spinels makes it possible to obtain rigid fire-safe PUFs with high physico-mechanical properties. Fire-safe rigid filling PUFs, developed with the use of raw native materials, are recommended to be used for low-temperature thermal insulation of pipelines and technological equipment.

DOI: 10.22227/1997-0935.2018.12.1524-1532

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HYDRAULICS. ENGINEERING HYDROLOGY. HYDRAULIC ENGINEERING

Role of transverse joints in regulation of the reinforced concrete face stress-strain state

  • Podvysotckii Aleksei A. - Mosoblgidroproekt Candidate of Technical Sciences, Head of Hydrotechnical Department, Mosoblgidroproekt, 1 Energetikov st., Dedovsk, 143532, Russian Federation.
  • Sainov Mikhail P. - Moscow State University of Civil Engineering (National Research University) (MGSU) Candidate of Technical Sciences, Associate Professor, Associate Professor of Department of Hydraulics and Hydraulic Engineering, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.
  • Soroka Vladislav B. - SpetsNovostroy engineer, SpetsNovostroy, 20 Communal quarter, Krasnogorsk, 143405, Russian Federation.
  • Lukichev Roman V. - Moscow State University of Civil Engineering (National Research University) (MGSU) bachelor Hydraulics and Hydraulic Engineering Department, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.

Pages 1533-1545

Introduction. Deals with the results of studying effectiveness of arranging transverse joints in the face as the means of regulation of its stress-strain state. At present reinforced concrete faces are constructed without being cut height-wise and transverse joints may be arranged only at the end of the dam construction stages. This is validated by the fact that experience in construction of flexible (discontinuous) faces has not demonstrated the required level of safety of this structural design. However, in the dams of the up-to-date structural designs, maintaining the face integrity is not guaranteed: cracks appeared in reinforced concrete faces at a number of high dams. Formation of cracks in faces should be attributed to presence of tensile stresses, whose values exceed concrete tensile strength. To prevent seal failure of the seepage-control element it is feasible to provide arrangement of the transverse joint in the face section where tensile stresses may be expected. Materials and methods. The studies were conducted on the example of a 100 m high dam with the aid of numerical modeling. Rockfill was considered as a lineally deformed material, but computations were conducted for a wide range of the soil linear deformation modulus: from 60 to 480 МPа. Steel reinforcement was considered in the face. Transverse joints were modelled with the aid of contact finite elements. Results. By the results of numerical modeling the tensile stresses appear in the uncut face due to bending deformations and deformations of longitudinal extension. The most hazardous is the face lower section. At this section the longitudinal tensile force and considerable moment are acting. Transverse joints are feasible to be arranged in this particular section of the face. Conclusion. It was revealed that the main positive effect of the transverse joint arrangement is in decreasing the value of longitudinal tensile force perceived by the face. Impact of the transverse joint on bending moments has a local effect and covers the section of the limited length. Moreover, at arranging joints the values of bending moments may increase. We may recommend arrangement of a transverse joint in the face which is parallel to the perimeter joints only in the face lower part which is subject to longitudinal deformation.

DOI: 10.22227/1997-0935.2018.12.1533-1545

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The throughput of filtering outlet works (filter spillways) on rockfill dams with screen

  • Malakhanov Vyacheslav V. - Moscow State University of Civil Engineering (National Research University) (MGSU) Candidate of Technical Sciences, Associate Professor at the Department of Hydrauliсs and Hydrauliс Engineering, Moscow State University of Civil Engineering (National Research University) (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation.

Pages 1546-1555

Introduction. The most economical type of spillway for rockfill dams with reinforced concrete screens are filtering outlet works (filter spillways). Deals with the main issue of designing filtering outlet works - assessment of their throughput on the basis of analytical solutions of turbulent filtration through the water intake of the filtering outlet works in rockfill dams with reinforced concrete screen. The objectives of the work are: • analysis of water flow in the filtering outlet work on the rockfill dam with reinforced concrete screen; • derivation of formulas for determining the throughput of the filtering outlet works on rockfill dams with reinforced concrete screen; • comparison of the results of determining the throughput of the filtering outlet works in the application of the proposed formulas; recommendations on the use of the proposed formulas. Materials and methods. The analysis of the water flow in the filtering outlet works and the derivation of the formulas is based on the adoption of three assumptions on the trajectory of the elementary streams of water in the filtering outlet works: on a circular trajectory, with a vertical fall, along the free fall trajectory with a gradient equal to one. Calculations of the throughput of the filtering outlet works were performed for the design of the filtering outlet works, patented by the author. Results. The results of calculations according to the proposed formulas showed a significant difference depending on the accepted hypothesis about the nature of the movement of the filtration flow in the body of the rockfill dam. It is revealed that the most acceptable calculations are based on the formula derived under the assumption of the flow motion along the free fall trajectory with a gradient equal to one. Conclusions. The results of the study made it possible to formulate the following recommendations: 1. The capacity of the filtering outlet works is recommended to be determined by the formula derived in the assumption of the flow motion along the free fall trajectory with a gradient equal to one, as more appropriate to the hydraulics of the filter spillways on the rockfill dams with the screen. 2. Further study of the hydraulics of the filter outlets works of various designs and analysis of their impact on the design of rockfill dams would allow for a more substantiated to determine their ability to pass the flood and recommend them for implementation.

DOI: 10.22227/1997-0935.2018.12.1546-1555

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