scholarly journals THE EFFECT OF COMPLEX MULTI-PURPOSE ADDITIVE ON OPERATING PROPERTIES OF HYDRATED CEMENT AND CONCRETE

2020 ◽  
Vol 22 (5) ◽  
pp. 139-152
Author(s):  
O. V. Dem'yanenko ◽  
A. A. Kulikova ◽  
N. O. Kopanitsa
Keyword(s):  
Materials Science ◽  
Physicochemical Analysis ◽  
Industrial Wastes ◽  
Cement Stone ◽  
Hydrated Cement ◽  
Fine Grain ◽  
Cement And Concrete ◽  
Required Quality ◽  
Mixing Water

The research developments in materials science in the construction field concerning the formulation and production process of fine-grain concrete are aimed at the formation of structure and properties that provide the appropriate performance characteristics. The literature review and experimental data on the concrete treatment made show that the required quality of concrete can be achieved by changing the concrete mixture composition, activation of aggregate and mixing water, introduction of multi-purpose modifying additives, different approaches, etc. The paper presents the development of the effective multi-purpose additive consisting of such industrial wastes as marble-microcalcite, nano silicon dioxide, microsilica, and peat hermally modified at 600 °C. The influence of this additive on hydrated cement and concrete properties is studied herein. It is shown that the introduction of the multi-purpose additive in an amount of 5 % with a decrease in the cement consumption, improves the compressive strength of hydrated cement stone up to 69 %. The chemical composition of new formations of modified hydrated cement is determined by the physicochemical analysis.

Fine Grain Concrete on Mixing Water Activated in Cavitation Permanent Magnet-Type Apparatus

2019 ◽  
Vol 816 ◽  
pp. 279-284 ◽  
Author(s):  
Marina A. Akulova ◽  
T.E. Slizneva ◽  
P.B. Razgovorov ◽  
Alla G. Sokolova
Keyword(s):  
Bending Strength ◽  
Magnetic Treatment ◽  
Cement Stone ◽  
Porous Space ◽  
Sodium Thiosulphate ◽  
Freeze Thaw ◽  
Fine Grain ◽  
The Impact ◽  
Mixing Water ◽  
Magnetic Activation

The authors obtained fine grain concrete based on the mortars of additives-electrolytes undergone mechanic magnetic activation and characterized by improved compression and bending strength and enhanced freeze-thaw resistance. There was investigated the impact of mechanic magnetic activation (MMA) on mixing water when adding calcium chloride and sodium thiosulphate as well as on porosity of cement stone and specific features of phase formation in cement stone. It was stated by the authors that MMA facilitates formation of nucleation centers in activated water in the presence of additives-electrolytes, optimization of porous space as well as crystallization of calcium carbonate in the form of aragonite when lowering the content of Portlandite. The mechanism of joined influence of hydrodynamic and magnetic treatment of mixing water has been determined.

Construction Control As A Strategy For Improving The Quality Of Buildings And Structures

2020 ◽  
Keyword(s):  
Quality Control ◽  
Life Cycle ◽  
Construction Control ◽  
Construction Sites ◽  
Actual Problem ◽  
Construction Market ◽  
Construction Products ◽  
Underlying Causes ◽  
Required Quality

In construction production, the safety of constructing buildings and structures is achieved by ensuring the required quality as a result of systematic construction control based on the implementation of a complex of technical, economic and organizational measures at all stages of the object's life cycle. The article deals with the actual problem of improving the quality of construction products-buildings and structures in conjunction with the activities of construction control bodies. The article presents the advanced foreign and domestic experience of ensuring the quality control at the construction sites, providing for the prevention of the underlying causes of defects and increasing the interest of the contractors directly. On the basis of the analysis of the current situation with quality control at the construction market, ways to improve its efficiency by developing a unified system of technological implementation of relevant requirements for the quality of construction products, determining the rational number and business load of construction control engineers, as well as the active activities of self-regulatory organizations in this area are offered.

Study Of Structure Formation Of Organic-Mineral Compositions With Fibrous Filler By Electron Microscopy Method

2019 ◽  
pp. 41-47
Keyword(s):  
Electron Microscopy ◽  
Structure Formation ◽  
Mineral Composition ◽  
Bending Strength ◽  
Cement Stone ◽  
Hydrated Cement ◽  
Fibrous Filler ◽  
Organic Mineral ◽  
Microscopy Method ◽  
Mineral Compositions

The article presents the study of processes of structure formation of cement stone and products of hardening of organic-mineral compositions with fibrous filler (shavings) by the electronic scanning microscopy method. It is established that the additive-free cement stone at the age of 28 days has a dense and homogeneous structure, consists of calcium hydro-silicates, Portlandite and calcite - newgrowths characteristic for cement systems. Cellulose fibers, which make up the bulk of the substance of shavings, are sufficiently active, which determines the high adhesion of the hydration products of the cement binder to their surface. It is shown that the introduction of shavings into the organo-mineral composition leads to inhibition of cement hydration processes. Organo-mineral compositions with different shavings content (two compositions) were analyzed. The first composition is characterized by a fairly dense structure, the cement stone consists of globular nanoscale nuclei of hydrosilicates, Portlandite and calcite. The second composition has a loose porous structure, cement stone consists of non-hydrated cement grains, newgrowths are represented by calcite and vaterite. The structure of the contact zone "osprey fiber-cement stone" in the organo-mineral composition of the first composition indicates a good adhesion of the filler surface with the phases of hydrated cement. The use of shavings as a fibrous filler (the first composition) increases the tensile and bending strength, as well as the wear resistance of organo-mineral compositions. The data obtained by scanning electron microscopy are confirmed by the results of studying the processes of structure formation of cement stone by quantitative x-ray phase analysis.

Conceptual imposings of quality management of system of production of composite materials for it is rocket the space equipment

2017 ◽  
Vol 14 (4) ◽  
pp. 30-38
Author(s):  
V. G. Isaev ◽  
T. N. Antipova
Keyword(s):  
Composite Materials ◽  
Quality Management ◽  
Evaluation Criteria ◽  
Criteria And Indicators ◽  
Properties Of Materials ◽  
A Priority ◽  
Required Quality

Basic provisions of the concept and methodology of production of composite materials for the missile and space equipment are offered. The system of the purposes realizing the principle of a priority of the purposes of the customer is offered. The system of evaluation criteria and indicators of quality of composite materials the realizing interrelation of requirements of the customer to quality of material and dependence of ensuring the required quality on the used technologies is developed. It is shown that for ensuring quality of composite materials for units and the RKT systems first of all it is necessary development of mathematical dependences of properties of materials on parameters of the technological modes in the conditions of obligatory implementation of requirements of the customer.

Coordination of technology of railway operation of the Republic of Tajikistan and organization of railways in international traffic

2018 ◽  
Vol 77 (4) ◽  
pp. 211-217 ◽  
Author(s):  
P. N. Pulatov
Keyword(s):  
Rolling Stock ◽  
Railway Transport ◽  
Transport Services ◽  
Railway Infrastructure ◽  
External Conditions ◽  
The Republic ◽  
Railway Operation ◽  
Required Quality

Current geopolitical and economic conditions for the functioning of railway transport in most post-Soviet states are such that it is extremely difficult to provide required quality of transport services and break-even operations at high expenses for maintaining the railway infrastructure and rolling stock. Dynamics of transportation of the Tajik Railway (TSR) is shown, which displays that most of its sections are classified as low-intensity ones. The paper proposes methodical principles, setting and qualitative analysis of the task of rationalization of operational work and organization of car flows for international transportation, taking into account the specifics of the Tajik Railway. There is a problem of complex maintenance of the efficiency of operational work in modern conditions based on the synthesis of the tasks of self-management (rational internal operational technology of the Tajik Railway) and coordination tasks (technological interaction with railway administrations of other states). Author substantiated the necessity of solving this problem. Proposed classification of technological restrictions and controlled variables in the performance of transport takes into account methods for changing external conditions for the functioning of the railway landfill and methods for increasing internal efficiency of its operation. The search for the solution of the problem involves direct search of variants along its ordered set with clipping of groups of variants that do not correspond to constraints, with the subsequent finding of compromise control over a set of effective alternatives.

scholarly journals The use of mathematical modelling to analyse the process of mixing waters from different sources in water supply system

2018 ◽  
Vol 59 ◽  
pp. 00025
Author(s):  
Agnieszka Szuster – Janiaczyk ◽  
Rafał Brodziak ◽  
Jędrzej Bylka
Keyword(s):  
Mathematical Modeling ◽  
Water Quality ◽  
Quality Criteria ◽  
Supply System ◽  
Network Control ◽  
Quality Of Water ◽  
Water Mains ◽  
Different Sources ◽  
Mixing Water

One of the processes that significantly determines the quality of water to consumers is the process of mixing water from different sources in the water mains. Put to the network two or more chemically and biologically stable waters may result in the formation of water that will be deprived of these features. This article presents the german guidelines for analysing water quality for mixing waters from different sources, in various proportions. Then performed an analysis of utility the mathematical models,including quality criteria, for use in network control. An IT tool has been developed to manage selected water quality processes using mathematical modeling. The basis for implementing the tool was a network model created in Epanet integrated with the Matlab.

scholarly journals A CDT-Based Heuristic Zone Design Approach for Economic Census Investigators

2015 ◽  
Vol 2015 ◽  
pp. 1-14 ◽  
Author(s):  
Changixu Cheng ◽  
Xiaomei Song ◽  
Jing Yang ◽  
Xiatian Hu ◽  
Shi Shen ◽  
...  
Keyword(s):  
Delaunay Triangulation ◽  
Real World ◽  
Heuristic Method ◽  
Real World Application ◽  
Economic Census ◽  
Speed Up ◽  
Growth Approach ◽  
Special Zone ◽  
Required Quality

This paper addresses a special zone design problem for economic census investigators that is motivated by a real-world application. This paper presented a heuristic multikernel growth approach via Constrained Delaunay Triangulation (CDT). This approach not only solved the barriers problem but also dealt with the polygon data in zoning procedure. In addition, it uses a new heuristic method to speed up the zoning process greatly on the premise of the required quality of zoning. At last, two special instances for economic census were performed, highlighting the performance of this approach.

Development of Mixture "Clay – Electro-Smelting Slag" for Ceramic Brick

2014 ◽  
Vol 682 ◽  
pp. 480-484 ◽  
Author(s):  
V.F. Torosyan ◽  
E.S. Torosyan
Keyword(s):  
Building Materials ◽  
Raw Materials ◽  
Ceramic Brick ◽  
Ceramic Samples ◽  
Manufactured Products ◽  
Smelting Slag ◽  
Compression Resistance ◽  
Mixing Water ◽  
Melting Slag

Industrial transition to a totally new level of resources and energy saving necessitates improving the technical level of building materials manufacturing, growing their raw materials base, the assortment, enhancing the quality of manufactured products, cutting their cost price. It requires, first of all, carrying out more detailed research in properties of clay and clay loams, and selecting optimal additives for pottery works. Such disadvantages of clays as burning sensitivity, low compression resistance and flexural strength in a burnt state, low frost resistance cause the impossibility of their application without corrective additives. It is quite difficult to find an additive which can solve all the technological problems mentioned above. This paper provides the development of mixture "clay – electro-melting slag" for ceramic brick, moreover, addition of a steel-smelting slag in the fusion mixture results in the change in mixing water content of ceramic masses, strength and coloration of ceramic samples.

Materials Science and Engineering Education

MRS Bulletin ◽  
1992 ◽  
Vol 17 (9) ◽  
pp. 18-21 ◽  
Author(s):  
R. Abbaschian
Keyword(s):  
Quality Of Life ◽  
Iron Age ◽  
Materials Science ◽  
Critical Role ◽  
Economic Security ◽  
Intraocular Lenses ◽  
Science And Engineering ◽  
Materials Science And Engineering ◽  
Do So

Materials science and engineering (MSE), as a field as well as a discipline, has expanded greatly in recent years and will continue to do so, most likely at an even faster pace. It is now well-accepted that materials are crucial to the national defense, to the quality of life, and to the economic security and competitiveness of the nation. Mankind has recognized the importance of manmade materials to the quality of life for many centuries. In many cases, the security and defense of tribes and nations have substantially depended on the availability of materials. It is not surprising that historical periods have been named after materials—the Bronze Age, the Iron Age, etc. The major requirements from materials in those days were their properties and performance. Today, in this age of advanced materials, the importance of materials to defense and quality of life has not changed. However, the critical role of materials has taken an additional dimension: it has become essential to enhancing industrial competitiveness.The knowledge base within MSE has also expanded vastly throughout these years and continues to do so at an increasing rate. We are constantly gaining a deeper understanding of the fundamental nature of materials, developing new ways to produce and shape them for applications extending from automobiles to supersonic airplanes, optoelectronic devices to supercomputers, hip implants to intraocular lenses, or from household appliances to gigantic structures. We are also learning that, in many of these applications, we need to depend on the combinations or composites of different classes of materials (metals, ceramic, polymers, and electronic materials) to enhance their properties.

Studying demulsifier reactants for crude oil processing facilities

2021 ◽  
pp. 90-104
Author(s):  
L. V. Taranova ◽  
A. G. Mozyrev ◽  
V. G. Gabdrakipova ◽  
A. M. Glazunov
Keyword(s):  
Crude Oil ◽  
Bottom Water ◽  
Oil Content ◽  
Optimal Consumption ◽  
Residual Oil ◽  
Well Production ◽  
Oil Processing ◽  
Water Cut ◽  
Required Quality

The article deals with the issues of improving the quality of highly watered well production fluid processing using chemical demulsifier reactants at crude oil processing facilities; the analysis of the use of the reactants at the Samotlor field has been made. The article presents the results of the study of the effectiveness of the "Hercules 2202 grade A" and "SNPH-4460-2" demulsifiers in comparison with the indicators of oil and bottom water processing achieved in the presence of the reactants used at existing facilities; their optimal consumption has been determined. The study has shown that the selected demulsifiers provide the required quality of the oil and water under processing at the considered oil processing facilities and can be used along with the basic reactants for these facilities. On the basis of total indicators, the best results have been achieved using "Hercules 2202 grade A" with the improved indicators of water cut and residual oil content in water by 33.9 % and 2.8 % while reducing the reactant consumption by 9.7 % compared to the basic demulsifier.

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