scholarly journals Backfill mixtures based on industrial waste

2021 ◽  
Vol 264 ◽  
pp. 01012
Author(s):  
Shavkat Rakhimov ◽  
Uchqun Gaziev ◽  
Nilufar Babakulova ◽  
Qunduz Khudoynazarova
Keyword(s):  
Mathematical Method ◽  
Portland Cement ◽  
Statistical Methods ◽  
Optimization Model ◽  
Industrial Waste ◽  
Mechanical Characteristics ◽  
Copper Smelting ◽  
Mathematical Methods ◽  
Quantitative Characteristics ◽  
Physical And Mechanical Characteristics

The object of the study is filling mixtures based on waste from the mining, energy, and copper-smelting industries, Portland cement, and superplasticizer. In the course of the study, standardized methods for studying the properties and quality indicators of industrial waste and filling mixtures based on it and mathematical methods for optimizing the compositions of mixtures, statistical methods for analyzing the results of experiments, were used. It has been established that, in terms of their physical and mechanical characteristics, stowing mixtures based on waste are not inferior to mixtures based on natural materials. The mathematical method for planning experiments has revealed the dependences linking strength with the quantitative characteristics of the components of the filling mixture. Based on the established regularities, an optimization model has been developed that minimizes the consumption of the binder and establishes a relationship between the composition and properties of the mixture.

Development of Cement Compositions with a Finely Dispersed Additive for Consolidation of Soil by the Injection

2019 ◽  
Vol 974 ◽  
pp. 149-155
Author(s):  
Irina V. Kozlova ◽  
Alexey E. Bespalov ◽  
Alexandra V. Bespalova
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Mechanical Characteristics ◽  
Cement Stone ◽  
Soil Consolidation ◽  
Injection Solution ◽  
Concentrated Load ◽  
Reduced Viscosity ◽  
Injection Technology ◽  
Physical And Mechanical Characteristics

Cement compositions prepared by mixing cement with a stabilized finely dispersed slag suspension, which allow improving the structural, physical and mechanical characteristics of the cement stone are considered. On the first day of hardening, the strength of modified specimens increased by 54%, at the grade age - by 43%, and the porosity decreased by 13.8 and 17.3%, respectively. The possibility of obtaining an injection solution for soil consolidation on the basis of Portland cement and a stabilized slag suspension with the concentration of a finely dispersed slag of 50 g/l is considered. Studies have shown that the injection solution under study has reduced viscosity and sedimentation, increased compressive strength. After 28 days of hardening, the strength was 14.2 MPa, which is higher than the recommended values ​​for consolidation of soil under the foundations (4-6 MPa), and at a concentrated load, for the base under the foundations of the columns (9-10 MPa). The data obtained allows considering an injection solution based on Portland cement and slag suspension for the use in the injection technology of soil consolidation.

Physical Nonlinearity and Anisotropic Features of Materials in Structure Analysis

2013 ◽  
Vol 405-408 ◽  
pp. 2686-2689 ◽  
Author(s):  
Nina S. Blokhina
Keyword(s):  
Mechanical Characteristics ◽  
Construction Materials ◽  
Physical Nonlinearity ◽  
Point Of View ◽  
Mathematical Methods ◽  
Construction Design ◽  
Plastic Yield ◽  
Newton Raphson ◽  
Raphson Method ◽  
Physical And Mechanical Characteristics

A justified assessment of the work of constructions and their elements should take into account physical and mechanical characteristics of construction materials. Although taking physical nonlinearity and anisotropic features into consideration will make the design more complicated, it is strongly needed to develop tools and methods that cover all the specific features of the material more precisely. Mathematical methods of construction design that take physical nonlinearity into account are quite well investigated. They are: Newton Raphson method; modified Newton Raphson method which differs from the original version by the fact that the stiffness matrix has to be calculated only once at the first iteration and remains the same for several further iterations and steps of load; the method of growing stiffness which is quite efficient in dealing with problems of physical nonlinearity, and so on. But certain difficulties appear as we consider these problems from the point of view of physics: the majority of strength and plastic-yield criteria are not implemented in design process yet. That is caused by complicated mathematics and a need for more experiment in order to determine the constants in use.

Cemented Mortar Matrices Densified with Organic Additions

2020 ◽  
Vol 841 ◽  
pp. 193-197
Author(s):  
Luis Colín Velázquez ◽  
Elia Mercedes Alonso Guzmán ◽  
Wilfrido Martínez Molina ◽  
Hugo Luis Chávez García ◽  
Maybelin Carolina García Chiquito ◽  
...  
Keyword(s):  
Portland Cement ◽  
Mechanical Characteristics ◽  
Corn Starch ◽  
Pulse Velocity ◽  
Cement Industry ◽  
Coarse Aggregates ◽  
Synthetic Materials ◽  
Fine Aggregates ◽  
Quality Material ◽  
Physical And Mechanical Characteristics

Nowadays, one of the biggest problems is the environmental contamination, which is attributed to a great variety of factors, among which is the construction, because one of the main synthetic materials most used is concrete, artificial material consisting of portland cement, fine aggregates, coarse aggregates and water, in the production and processing of portland cement a large amount of carbon dioxide (CO2) is generated, by 2018 approximately 8% of CO2 emissions from the world is attributed to the cement industry. As a solution to this problem, substitutions and additions to portland cement are proposed, which will generate a reduction in consumption and processing by having a more durable and better quality material in terms of physical and mechanical characteristics. Additions of 2% are made with respect to the weight of the cement of organic additions, which do not affect the behavior of the mortar. Cubic specimens were developed for tests of pulse velocity, compressive stress and accelerated attack of sodium sulfate to determine the durability of the material, where favorable results were obtained with organic addition of corn starch.

scholarly journals Mathematical and cartographic methods of atmospheric processes’ analysis

2018 ◽  
Keyword(s):  
Mathematical Method ◽  
Functional Dependence ◽  
Temporal Structure ◽  
Mathematical Statistics ◽  
Economic Damage ◽  
Agricultural Crops ◽  
Natural Phenomena ◽  
Mathematical Methods ◽  
Atmospheric Processes ◽  
Quantitative Characteristics

Formulation of the problem. The urgency of the problem posed is the need to take into account the degree of intensity and quantitative study of dangerous atmospheric processes that cover large areas and cause significant economic damage to agriculture. When solving these questions it is necessary to have an objective estimation of different factors impact including weather and climate on the level of agricultural production. This will allow to assess various indicators of agro-meteorological conditions more reasonably in the estimation of the cereal harvest. Analysis of recent research and publications. The study of atmospheric processes and their effect on agricultural crops are devoted to in the works of V.V. Dokuchaev, P.I. Brоunоv, P.І. Kоlоskоv, G.Т. Sеlyaninov А.M. Аlpаtev S.А. Sаpоzhnikоvа, I.E. Buchinsky, N.B. Bova, V.A. Volevaha, V. Romushevich, Yu.І. Chirkоv, М.І. Budykо, А.R. Коnstаntіnоv, G.P. Dubinskiy. Formation of the purpose of the article. The article considers the questions of scientific research application and cartographical and mathematical methods. The following tasks are defined: to study the initial preconditions and methodological support in the study of this problem; to analyze the data of hydrometeorological service; to determine the empirical relationships of the spatial-temporal structure in the development of arid phenomena on the territory of Kharkiv region. Presentation of the main research material. In this paper, an attempt is made to use quantitative characteristics of environmentally hazardous atmospheric phenomena development for the analysis of their formation and influence on human economic activity. To do this, we used a cartographic and mathematical method of research. It consists in the fact that natural phenomena and, in particular, environmentally dangerous ones are placed on a map in the system of conditional signs and then are analyzed by methods of mathematical statistics, quantitative characteristics of the investigated phenomenon. The apparatus of mathematical statistics helps to solve probabilistic tasks of cartographic representation of natural phenomena, as well as to study various connections between natural phenomena reflected on maps, to measure and assess them. Involvement of the mathematical apparatus in the study of the cartographic image stems from the need for in-depth knowledge of the phenomena essence depicted in the maps. The study of natural phenomena without application of the map-mathematical method is considered to be one-sided since this does not take into account one of the important aspects of any study - quantitative relations and regularities. The result of the research is an analysis of statistical indicators of agricultural crops harvest and hydrometeorological conditions in Kharkiv region. Having analyzed these indicators, we determined that quantitative dependence of the crop on the number of dry days has a complex nonlinear multi-parameter appearance. At the same time, close connection between the harvest of corn and sugar beets with weather conditions was very significant, as indicated by the large correlation coefficient between them, equal to 0.87-0.90. We worked out a hypothesis about the form of functional dependence between these components. Using the mathematical modeling method to analyze the spatio-temporal structure of natural-anthropogenic phenomenon development allows us to unify the hydrometeorological characteristics. It can be used in different fields of science, in particular, in recreational geography. The apparatus of mathematical statistics helps to reliably solve the cartographic representation tasks of natural phenomena, as well as to study the versatile links between natural and anthropogenic objects, which are reflected on the maps, measure and estimate them. Conclusions. Cartographic and mathematical research method is an important component in the study of natural phenomena and processes and helps to solve probabilistic tasks of cartographic representation of natural phenomena, as well as to study the versatile relationships between natural phenomena reflected on maps, measure and quantitatively assess them.

scholarly journals ANALYSIS OF THE SURFACE PROPERTIES OF ZIZIPHUS JOAZEIRO MART. AND ITS PHYSICAL AND MECHANICAL EFFECTS UNDER PORTLAND CEMENT MORTAR

2021 ◽  
Keyword(s):  
Portland Cement ◽  
Mechanical Characteristics ◽  
Cement Mortar ◽  
Physical And Mechanical Properties ◽  
Mechanical Resistance ◽  
Surfactant Properties ◽  
Mechanical Effects ◽  
Natural Surfactant ◽  
Natural Surfactants ◽  
Physical And Mechanical Characteristics

Surfactants are products widely used in many segments of the industry and because they exhibit many properties they can intensify or improve some properties of the products in which they are used. Natural surfactants are obtained by isolating material of animal or vegetable origin without undergoing chemical changes in its structure. An example of a natural surfactant is that obtained from the Juá husk. Considering the relevance of Juá for obtaining natural surfactants, this work will analyze the effects on physical and mechanical properties that the incorporation, in different proportions, of the powder additive produced from the husk of the trunk of Ziyphus Joazeiro Mart. can offer Portland cement mortar CP-II - Z. The study was carried out at the IFPB - Campus Cajazeiras facilities. Tests were carried out that seek to evaluate the surfactant properties provided by Ziziphus Joazeiro Mart. and its physical and mechanical effects in the mortar. The production of Portland cement mortar combined with the “husk” additive of Ziyphus Joazeiro may be able to result in structures with optimized physical and mechanical characteristics, especially with regard to the consumption of water in the mixture of water, aggregate and binder, in workability and mechanical resistance, consequences resulting from the surfactant properties inherent in the studied composite

scholarly journals STUDY OF THE PHYSICAL AND MECHANICAL CHARACTERISTICS OF HIGHLY FILLED SLAG-CONTAINING CEMENTS MODIFIED WITH ORGANIC-MINERAL ADDITIVES PRODUCED BY BAUCHEMI

2020 ◽  
pp. 129-138
Author(s):  
A.A. Moskalenko ◽  
Keyword(s):  
Portland Cement ◽  
Mechanical Characteristics ◽  
Physical And Mechanical Properties ◽  
Simultaneous Increase ◽  
Mineral Complex ◽  
Organic Mineral ◽  
Artificial Stone ◽  
Mineral Additives ◽  
Physical And Mechanical Characteristics ◽  
Slag Content

Abstract. The physical and mechanical characteristics of highly filled slag cements modified by the organic-mineral complex of LLC “MC Bauhemi” have been investigated. As a result of optimization, the area of permissible concentrations of organic-mineral additives was established according to the maximum criteria for the timing of the beginning and end of setting and strength in compression at the age of 7 and 28 days. It is shown that the expansion of the beginning of setting and its end is positively influenced by the presence of the plasticizer MC-PowerFlow 2695 from 0.43 to 0.8% and the organic-mineral complex Centrilit NC and Centrilit Fume SX in an amount from 3 / 5.25 to 5.2 / 7%, that with a simultaneous increase in the slag content from 50 to 70% in the composition of Portland cement, the start-end time of setting increases from 225/250 to 320/330 minutes, which is 1.3 / 1.5 times higher than similar indicators of no additive Portland cement. It was noted that at the age of 7 and 28 days, the introduction of an organic-mineral complex of the composition MC-PowerFlow 2695 from 0.28 to 0.64%, Centrilit NC from 4.23 to 7% and Centrilit Fume SX from 3 to 7% and at the content of GDSH in the amount of 50 and 70% contributes to the production of an artificial stone of the M500 brand with compressive strength in the range of 47 / 52.8 and 46/48 MPa. Using the method of superposition of response functions, the optimal area of permissible concentrations of the components of the Bauhemi organic-mineral complex, affecting the stated criteria, was determined when the slag content in Portland cement was 50 and 70%, namely: 0.6% MC-PowerFlow 2695, 5% Centrilit NC and 5 % Centrilit Fume SX. Further research will be aimed at studying the effect of this complex on the physical and mechanical properties with a slag content of 50 and 70% in the composition of Portland cement.

Mathematical Formalism and Political-Economic Content

2012 ◽  
pp. 82-95 ◽  
Author(s):  
D. Foley
Keyword(s):  
Political Economy ◽  
Statistical Methods ◽  
Complex Adaptive System ◽  
Economic Modeling ◽  
Qualitative Properties ◽  
Mathematical Methods ◽  
Econometric Methods ◽  
Statistical Fluctuations ◽  
Complex Adaptive ◽  
New Thinking

Mathematical methods are only one moment in a layered process of theory generation in political economy, which starts from Schumpeterian vision, progresses to the identification of relevant abstractions, the development of mathematical and quantitative models, and the confrontation of theories with empirical data through statistical methods. But today the relevant abstract problems of political economy are modified to fit available mathematical tools. The role of empirical research in disciplining theoretical speculation, on which the scientific traditions integrity rests, was undermined by specific limitations of nascent econometric methods, and usurped by ex cathedra methodological fiats of theorists. These developmentssystematically favored certain ideological predispositions of economicsas a discipline. There is abundant room for New Thinking in political economy starting from the vision of the capitalist economy as a complex, adaptive system far from equilibrium, including the development of the theory of statistical fluctuations for economic interactions, redirection of macroeconomics and financial economics from path prediction toward an understanding of the qualitative properties of the system, introduction of constructive and computable methods into economic modeling, and the critical reconstruction of econometric statistical methods.

Mathematical Method to Unfolding Couplings

2019 ◽  
Vol 17 (17) ◽  
pp. 63-64
Author(s):  
Carmen Popa ◽  
Ivona Petre ◽  
Ruxandra-Elena Bratu
Keyword(s):  
Mathematical Method ◽  
Mathematical Methods ◽  
Intersection Curves ◽  
Four Cylinders

AbstractThe purpose of this paper is to establish the intersection curves between cylinders, using Mathematica program. The equations curves which are inferred by mathematical methods are introduced in this program. This paper takes into discussion the case of four cylinders.

Evaluating Micro-Structure, Hydration and Thermal Expansions of Cement Containing Nano-Silica

GIS Business ◽  
2020 ◽  
Vol 15 (1) ◽  
pp. 158-165 ◽  
Author(s):  
Dr. Sarvesh PS Rajput
Keyword(s):  
Portland Cement ◽  
Mechanical Characteristics ◽  
Microstructural Properties ◽  
Nano Silica ◽  
Micro Structure ◽  
Microstructural Characteristics ◽  
Mechanical And Microstructural Properties

This study reported that the addition of nano-silica enhances the mechanical characteristics of concrete as its compressive, flexural and tensile split strengths are increased. As a comparison mixture to equate it along with nano-modified concrete, ordinary samples of Portland cement (OPC) have been utilized. Herein, upto 6.0 percent of OPC has been substituted by nanosilica. In fact, the introduction of nanosilica improves mechanical and microstructural characteristics of concrete by significantly (28 to 35%). The finding therefore, indicated that partly replacing OPC with up to 5 percent nanosilica increases the mechanical and microstructural properties cured up to ninety days as opposed to the standard OPC mix.

Sign in / Sign up

Export Citation Format

Share Document