Regulation the Properties of Materials on Magnesia Binder

2017 ◽  
Vol 265 ◽  
pp. 856-861
Author(s):  
V.V. Zimich
Keyword(s):  
Water Resistance ◽  
High Strength ◽  
Modifying Additives ◽  
Different Types ◽  
Properties Of Materials ◽  
Mineral Additives ◽  
Magnesia Material ◽  
Stone Density ◽  
By Products ◽  
Active Mineral Additives

Industrial waste pollution in the cities and the areas beyond them is a burning issue today. The only solution is recycling the by-products of primary production. Thus, the magnesia caustics are widely used in construction. However, their application is limited due to their high hygroscopicity. Many scientists were involved into the study of this problem justifying their achieved positive result by either using different types of sealers or introduction of fine composition active mineral additives into the binder. Moreover, all these studies mainly focused on the improvement of the water resistance of magnesia composites, while hygroscopic regulation was not significant. So it is important to study the process of environmental moisture accumulation in the pores of the magnesia material. When establishing the causes of the high hygroscopicity of magnesium materials, it was found that its value depends on environmental conditions (temperature, pressure and relative humidity); the specific surface area of magnesia stone; density of the sealer for magnesia binder; the chemical composition of various modifying additives and their influence on the properties of magnesia stone and materials based on it; the composition of the hydrated phases of magnesia stone with additives and without them; the presence of pores, their size and number in the structure of the stone; the surface charge of a magnesia stone. Studies have shown that high-strength water resistant chlorine magnesia stone in combination with modifying additives allows obtaining a composite material with hygroscopicity less than 2 %.

scholarly journals Abrasive Wear Resistance of Concrete in Connection with the Use of Crushed and Mined Aggregate, Active and Non-Active Mineral Additives, and the Use of Fibers in Concrete

2020 ◽  
Vol 12 (23) ◽  
pp. 9920
Author(s):  
Lenka Bodnárová ◽  
Martin Ťažký ◽  
Lucia Ťažká ◽  
Rudolf Hela ◽  
Ondřej Pikna ◽  
...  
Keyword(s):  
Abrasion Resistance ◽  
Age Groups ◽  
High Strength ◽  
Mineralogical Composition ◽  
Concrete Mixtures ◽  
Standard Procedures ◽  
Different Types ◽  
The Impact ◽  
Mineral Additives ◽  
Active Mineral Additives

Virtually every concrete structure comes into contact with abrasive effects of flowing media or solids, which have a direct impact on the durability of concrete. An abrasive effect is most pronounced in transport or water management structures, and these structures are often designed for a significantly longer service life (usually 100 years). This research evaluates the influence of the filler component in terms of the type of aggregate and its mineralogical composition on concrete abrasion resistance. As part of the impact of the binder component, several concrete mixtures were produced using the same aggregate and maintaining the same strength class with the addition of different types of active and inert mineral additives. In other parts of the research, the effect of adding fiber reinforcement on the abrasion resistance of concrete was verified. Mutual connections and correlations in different age groups (7, 28 and 90 days) were sought for all obtained results. The abrasion resistance of the composite was monitored by using standard procedures, especially using a Böhm device. It was found that for good abrasion resistance of concrete, it is not necessary to produce concretes with high strength classes using often expensive mineral additives (microsilica) and quality aggregates, but the maturation time of the composite and its microstructure plays an important role.

scholarly journals Effect of electrolytes with multicharged cations on the strength of stone made of a modified mixed air binder

2021 ◽  
Vol 2131 (4) ◽  
pp. 042091
Author(s):  
N N Shangina ◽  
T Y Safonova
Keyword(s):  
Compressive Strength ◽  
Aluminum Sulfate ◽  
High Strength ◽  
Hydrated Lime ◽  
X Ray ◽  
Calcium Hydrosilicates ◽  
Granulated Slag ◽  
Mineral Additives ◽  
Mixing Water ◽  
Active Mineral Additives

Abstract The possibility of obtaining mixed air binder of high strength and water resistance by using active mineral additives has been considered. In this work, the gypsum binder has been replaced by a combination of hydrated lime with active additives - metakaolin and granulated slag. The ratio effect of the silica component to the binder on the compressive strength of the stone was studied. According to the results of X-ray phase analysis, the presence of tobermorite-like calcium hydrosilicates and the absence of hydrate lime phase were diagnosed in the stone. The influence of electrolyte additives - salts with three-charged cations - on stone hardening kinetics is shown. Increase in the compressive strength of 28-day-old stone from the modified mixed air binder by 5% with the introduction of 1% of the binder mass aluminum sulfate in the mixing water was established. The use of FeCl3 solution for mixing the modified mixed air binder leads to a decrease in the compressive strength of the 28-day-old stone. The mixing of the modified mixed air binder with Al2(SO4)3 solution reduces the time of setting.

Soy meal adhesive with high strength and water resistance via carboxymethylated wood fiber-induced crosslinking

Cellulose ◽  
2021 ◽  
Author(s):  
Huiwen Pang ◽  
Yuyang Wang ◽  
Zhiwei Chang ◽  
Changlei Xia ◽  
Chunrui Han ◽  
...  
Keyword(s):  
Water Resistance ◽  
Wood Fiber ◽  
High Strength ◽  
Soy Meal

scholarly journals Enhanced Water Resistance of Recycled Newspaper/High Density Polyethylene Composite Laminates via Hydrophobic Modification of Newspaper Laminas

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 421
Author(s):  
Binwei Zheng ◽  
Weiwei Zhang ◽  
Litao Guan ◽  
Jin Gu ◽  
Dengyun Tu ◽  
...  
Keyword(s):  
Stearic Acid ◽  
Photoelectron Spectroscopy ◽  
Composite Laminates ◽  
High Density Polyethylene ◽  
Water Resistance ◽  
Laminated Composite ◽  
High Strength ◽  
High Water ◽  
High Density ◽  
X Ray

A high strength recycled newspaper (NP)/high density polyethylene (HDPE) laminated composite was developed using NP laminas as reinforcement and HDPE film as matrix. Herein, NP fiber was modified with stearic acid (SA) to enhance the water resistance of the NP laminas and NP/HDPE composite. The effects of heat treatment and SA concentration on the water resistance and tensile property of NP and composite samples were investigated. The chemical structure of the NP was characterized with X-ray diffractometer, X-ray photoelectron spectroscopy and attenuated total reflectance Fourier transform infrared spectra techniques. The surface and microstructure of the NP sheets were observed by scanning electron microscopy. An expected high-water resistance of NP sheets was achieved due to a chemical bonding that low surface energy SA were grafted onto the modified NP fibers. Results showed that the hydrophobicity of NP increased with increasing the stearic acid concentration. The water resistance of the composite laminates was depended on the hydrophobicity of the NP sheets. The lowest value of 2 h water absorption rate (3.3% ± 0.3%) and thickness swelling rate (2.2% ± 0.4%) of composite were obtained when the SA concentration was 0.15 M. In addition, the introduction of SA can not only enhance the water resistance of the composite laminates, but also reduce the loss of tensile strength in wet conditions, which shows potential in outdoor applications.

scholarly journals Forecasting the properties of linear block-copoliurethanes based on oligoesters of regular structure

2021 ◽  
pp. 4-10
Author(s):  
V.N. Anisimov ◽  
◽  
V.V. Anisimov
Keyword(s):  
Molecular Structure ◽  
Regular Structure ◽  
High Strength ◽  
Operating Conditions ◽  
Properties Of Materials ◽  
Reasonable Choice ◽  
The Relationship ◽  
Tribotechnical Characteristics ◽  
Quality Indexes ◽  
Linear Block

We showed that the development of recommendations for a reasonable choice of linear block copolyurethanes that would be optimal for given operating conditions is still intuitive and does not consider the features of the molecular structure and the nature of initial components. We suggested a new scientifically grounded approach to the creation of linear block-copolyurethanes with increased wear resistance in relation to strength, deformation, thermophysical and tribotechnical characteristics. To simplify analysis of the properties of the studied materials, a mathematical model was developed, which describes the relationship between all considered properties of materials and their structure. We proposed to assess the relationship between structure and properties of the investigated materials by using quality indexes. Maximum values of quality indexes, depending on the operating conditions, correspond to different contents of hard blocks (Pc), and, consequently, to different molecular structure of the studied polyurethanes. Thus, it is reasonable to use block-copolyurethanes based on OBGA500 with a maximum content of hard blocks (Рс>60%) for operating conditions where it is necessary to provide high strength characteristics. Polyurethanes synthesized with the formation of clusters of hard blocks in the range of 45–55% are recommended for the use as wear-resistant materials.

Experimental study on seismic behaviors of beam with concrete-encased steel truss

2018 ◽  
Vol 21 (13) ◽  
pp. 2018-2029
Author(s):  
Xide Zhang ◽  
Zhiheng Deng ◽  
Xiaofang Deng ◽  
Jingwei Ying ◽  
Tao Yang ◽  
...  
Keyword(s):  
High Strength ◽  
Force Model ◽  
Restoring Force ◽  
Restoring Force Model ◽  
Steel Truss ◽  
Different Types ◽  
Energy Dissipation Capacity ◽  
Load Displacement ◽  
Strength And Stiffness ◽  
Seismic Behaviors

To evaluate the ductility and energy dissipation capacity of the beam with concrete-encased steel truss, eight specimens with different types of steel truss, reinforcement ratios, and shear span ratios were tested by low-cyclic loading regime. The results indicated that beams with concrete-encased steel truss performed plumped load–displacement hysteretic loops as well as high strength and stiffness. Moreover, cross-web members improved their seismic behavior more effectively than non-cross-web members. Finally, the restoring force model of concrete-encased steel truss beam is proposed in accordance with the experimental results, which can be used to predict the load–displacement behavior of concrete-encased steel truss beam. The results could also provide a reference for the design and application of concrete-encased steel truss beam in practice.

scholarly journals Effect of Mineral Admixtures on the Sulfate Resistance of High-Strength Piles Mortar

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3500
Author(s):  
Yanyan Hu ◽  
Linlin Ma ◽  
Tingshu He
Keyword(s):  
Blast Furnace ◽  
Fly Ash ◽  
Blast Furnace Slag ◽  
High Strength ◽  
Mineral Admixtures ◽  
Quartz Powder ◽  
Sulfate Resistance ◽  
Powder Samples ◽  
Mineral Additives ◽  
Furnace Slag

Pre-stressed high-strength concrete piles (PHCP) are widely used in the building industry in China. The main aim of our research was to investigate the utilization of quartz powder, fly ash, and blast furnace slag as mineral additives to prepare PHCP mortar. The samples were prepared using steam and autoclaving steaming. The influence of minerals on the sulfate resistance of mortar was analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP) tests. The results showed that when compared to single doped quartz powder samples, samples prepared using fly ash or blast furnace slag improved the sulfate resistance of the PHCP mortar. Furthermore, the resistance to sulfate attack of samples with dual doped quartz powder, fly ash, and blast furnace slag also improved. MIP tests showed that mineral additives can change the pore size distribution after autoclave curing. However, the number of aching holes increased after mixing with 20% quartz powder and caused a decrease in the sulfate resistance.

EcoLexicon and by-products

Terminology ◽  
2019 ◽  
Vol 25 (2) ◽  
pp. 222-258 ◽  
Author(s):  
Pilar León-Araúz ◽  
Arianne Reimerink ◽  
Pamela Faber
Keyword(s):  
Semantic Web ◽  
Knowledge Representation ◽  
Knowledge Base ◽  
Visual Information ◽  
Environmental Science ◽  
Image Annotation ◽  
Open Data ◽  
Annotation Tool ◽  
Different Types ◽  
By Products

Abstract Reutilization and interoperability are major issues in the fields of knowledge representation and extraction, as reflected in initiatives such as the Semantic Web and the Linked Open Data Cloud. This paper shows how terminological resources can be integrated and reused within different types of application. EcoLexicon is a multilingual terminological knowledge base (TKB) on environmental science that integrates conceptual, linguistic and visual information. It has led to the following by-products: (i) the EcoLexicon English Corpus; (ii) EcoLexiCAT, a terminology-enhanced translation tool; and (iii) Manzanilla, an image annotation tool. This paper explains EcoLexicon and its by-products, and shows how the latter exploit and enhance the data in the TKB.

Properties of Composite Gypsum Binders Depending on Multicomponent Mineral Additives

2019 ◽  
Vol 945 ◽  
pp. 238-243 ◽  
Author(s):  
Valery S. Lesovik ◽  
N.V. Chernysheva ◽  
M.Yu. Drebezgova
Keyword(s):  
Portland Cement ◽  
Magnetic Separation ◽  
Water Resistance ◽  
Cement Hydration ◽  
Raw Materials ◽  
Crystal Formation ◽  
Calcium Hydrosilicates ◽  
Nanodispersed Silica ◽  
Mineral Additives ◽  
Ferruginous Quartzites

This article considers the possibility of increasing the effectiveness of composite gypsum binders (CGB) by controlling the processes of structure formation as a result of using new types of multicomponent mineral additives that are significantly different from the traditionally used quartz raw materials:- waste of wet magnetic separation of ferrous quartzites (WMS waste,) of polymineral composition with quartzy of varying degrees of crystallinity, nanodispersed silica and chalk powder. We have studied the cause-effect relationship between the change in the ratio of binding and mineral additives of various compositions, which determines the conditions for the formation of technological and strength characteristics of the projected composite materials with specified performance properties. We have established the presence of regularities in the changes in the properties of CGB, the composition of the hardening products and the microstructure depending on the type and content of gypsum binders of β-and α-modifications, portland cement, multicomponent finely-dispersed mineral additives, the regularity consists in the binding of portlandite, which is released upon portland cement hydration, by the amorphous phase of earth siliconas a part ofnanodispersed powder and chalcedony variety of quartz waste of wet magnetic separation of ferruginous quartzites. This provides a reduction in the basicity of the solidifying system, the intensification of crystal formation, and the formation of newgrowths with a high content of tobormorite-low-basic calcium hydrosilicates that compact the microstructure of the hardening matrix and, as a result, increase the water resistance and stability. It is noted that this mechanism of hydration of CGB minimizes inner stresses and volume deformations, therefore the number of microcracks decreases, which leads to an increase in its efficiency in comparison with the traditionally used gypsum binder and that differs from the traditional portland cement by a fast strength generation.

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