Effects of different allocation approaches for modeling mineral additives in blended cements on environmental damage from five concrete mixtures in Israel

2016 ◽  
Vol 49 (10) ◽  
pp. 4401-4415 ◽  
Author(s):  
Svetlana Pushkar ◽  
Oleg Verbitsky
Keyword(s):  
Environmental Damage ◽  
Blended Cements ◽  
Concrete Mixtures ◽  
Mineral Additives

scholarly journals Sustainable Development of the Cement Industry and Blended Cements to Meet Ecological Challenges

2003 ◽  
Vol 3 ◽  
pp. 308-318 ◽  
Author(s):  
Konstantin Sobolev
Keyword(s):  
Technological Development ◽  
High Volume ◽  
Cement Industry ◽  
Cement Clinker ◽  
Blended Cements ◽  
Mineral Additive ◽  
Reduction Of Energy Consumption ◽  
Special Complex ◽  
Mineral Additives ◽  
By Products

The world production of cement has greatly increased in the past 10 years. This trend is the most significant factor affecting technological development and the updating of manufacturing facilities in the cement industry. Existing technology for the production of cement clinker is ecologically damaging; it consumes much energy and natural resources and also emits pollutants. A new approach to the production of blended or high-volume mineral additive (HVMA) cement helps to improve its ecological compatibility. HVMA cement technology is based on the intergrinding of portland cement clinker, gypsum, mineral additives, and a special complex admixture. This new method increases the compressive strength of ordinary cement, improves durability of the cement-based materials, and - at the same time - uses inexpensive natural mineral additives or industrial by-products. This improvement leads to a reduction of energy consumption per unit of the cement produced. Higher strength, better durability, reduction of pollution at the clinker production stage, and decrease of landfill area occupied by industrial by-products, all provide ecological advantages for HVMA cement.

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 POSSIBILITY OF USING VOLCANIC ROCKS IN THE CEMENT INDUSTRY

2019 ◽  
Author(s):  
В.А. Байтиев ◽  
Р.Г. Бисултанов ◽  
М.Ш. Саламанова ◽  
С-А. Ю. Муртазаев
Keyword(s):  
Strength Class ◽  
Volcanic Rocks ◽  
Cement Industry ◽  
Normal Density ◽  
High Quality ◽  
Volcanic Origin ◽  
Concrete Mixtures ◽  
Mineral Additives ◽  
Composite Cements ◽  
Active Mineral Additives

В данной статье раскрываются особенности формирования структуры цементных композиций с применением активной минеральной добавки вулканического происхождения. Полученные ре цептуры композиционных цементов позволят получать высококачественные бетоны с классом прочности от В60 до В100, снижать нормальную густоту бетонных смесей на 2530, при этом подвижность смеси остается постоянной. Кроме того, применение данной разработки позволит повышать темпы набора прочностных показателей бетона, что дает вероятность отказа от тепло вой обработки и способствует получению необходимой для распалубки прочности за промежуток времени 1824 часов. Работа выполнена в рамках исследований по реализации научного проекта 1848-200001 Высококачественные бетоны с повышенными эксплуатационными свойствами на основе местного природного и техногенного сырья , получившего поддержку Российского фонда фундаментальных исследований (РФФИ). The article reveals the features of the formation of the structure of cement compositions using active mineral additives of volcanic origin. The resulting composition of composite cements will make it possible to obtain high-quality concrete with a strength class from B60 to B100, reduce the normal density of concrete mixtures by 2530, while the mobility of the mixture remains constant. In addition, the use of this development will allow increasing the pace of a set of strength indicators of concrete, which gives the probability of refusal from heat treatment and helps to obtain the strength necessary for stripping for a period of 1824 hours.

scholarly journals PROSPECTS FOR THE DEPOSITS DEVELOPMENT IN OSSETIA

2021 ◽  
Vol 13 (1) ◽  
pp. 103-111
Author(s):  
Vladimir GOLIK ◽  
◽  
Yuri DMITRAK ◽  
Oleg GABARAEV ◽  
Igor ZASSEEV ◽  
...  
Keyword(s):  
Construction Industry ◽  
Raw Materials ◽  
Economic Modeling ◽  
Theory And Practice ◽  
Alternative Methods ◽  
Environmental Damage ◽  
Second Stage ◽  
Concrete Mixtures ◽  
The Cost ◽  
Universal Scheme

Goal. Substantiation of the ecological and economic efficiency of innovative technologies for the development of deposits of the Sadonsky ore cluster during the period of restoration of the lost industrial potential of the depressed region. Methods. Analysis of the theory and practice of mining, with priority given to the experience in the development of North Caucasian deposits. Laboratory experiment in the study of the properties of filling mixtures and options with different activation methods, including reagent leaching in a disintegrator. Mathematical and economic modeling of the efficiency of recycling tailings utilization at the cost of commercial products, taking into account the prevented environmental damage. Results. The information on the dynamics of mining and processing of ores from the Sadonsky deposits is presented. The results of studies of the properties of base concrete mixtures based on ore dressing tailings and local available components are systematized and generalized. The results of changes in the properties of hardening mixtures are given depending on the presence of metals in the tailings of enrichment with various activation options by alternative methods, including an innovative method of mechanochemical leaching in a disintegrator with electrochemically activated water. The equivalent of 1 kg of cement using binders from processing tailings has been determined. The advantages of mechanochemical activation of tailings in a disintegrator in comparison with the option of irrigation by irrigation using various reagents have been experimentally determined. A quantitative indicator of an increase in the strength of the compositions of hardening mixtures under equal conditions has been established. The efficiency of utilization of tailings and metallurgy has been determined as a set of effects of reducing the amount of environmental damage from storage of tailings, the cost of metals obtained during processing, raw materials for the construction industry and associated marketable products. The nomenclature of tailings processing products has been detailed. A model for determining the profit from processing tailings and metallurgy is recommended. A forecast is given at the level of engineering expertise of the prospects for tailings processing. The hardware diagram of the tailings disposal section is detailed. A universal scheme for the disposal of mining and processing waste was recommended. Conclusion. The prospects for the development of the deposits of the Sadonsky ore cluster depend on conversion to technologies with filling voids with solidifying mixtures and leaching of metals at the processing stages. The combined mining technology will reduce the output of tailings, strengthen the base of the construction industry, eliminate the need to build a second stage of tailings and improve the environment.

scholarly journals STUDY OF SORPTIVITY OF SELF‐COMPACTING CONCRETE WITH MINERAL ADDITIVES

2006 ◽  
Vol 12 (3) ◽  
pp. 215-220 ◽  
Author(s):  
Luiz Antonio Pereira de Oliveira ◽  
João Paulo de Castro Gomes ◽  
Cristiana Nadir Gonilho Pereira
Keyword(s):  
Fly Ash ◽  
The Self ◽  
Capillary Absorption ◽  
Self Compacting Concrete ◽  
Normal Concrete ◽  
Hydraulic Lime ◽  
Concrete Mixtures ◽  
Slump Flow ◽  
Different Types ◽  
Mineral Additives

This work presents the results of a comparative study of the sorptivity, accomplished in mixtures of selfcompacting concrete with different types of additives and a normal concrete compacted by vibration. The self‐compacting concrete mixtures present slump‐flow of 650 ± 50 mm and have the same cement contents. In the self‐compacting mixtures, were used as additives, fly ash, silica fume, hydraulic lime and a mixture of fly ash and hydraulic lime. A modified carboxylates superplasticiser was used to obtain a specific workability. The capillary absorption was carried out at 7, 14 and 28 days of age, through a methodology described in the work. The results permit to conclude that the used additives propitiate the self‐compacting concrete. In terms of capillary absorption, the mixtures with fly ash have a better performance.

The Relationship between Mechanical Properties and Shrinkage of the Concretes Used in Florida

2012 ◽  
Vol 204-208 ◽  
pp. 3799-3804
Author(s):  
Yan Jun Liu ◽  
Mang Tia
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Empirical Relationship ◽  
Lightweight Aggregate ◽  
Shrinkage Strain ◽  
Coarse Aggregates ◽  
Concrete Mixtures ◽  
The Relationship ◽  
Mineral Additives

This paper investigated the mechanical strength and shrinkage properties of the concrete mixtures frequently used in Florida. The concrete mixtures were proportioned with three different types of coarse aggregates, such as Miami Oolite limestone, Georgia granite and Stalite lightweight aggregate, and two mineral additives, including fly ash and slag. And fourteen concrete mixtures were evaluated on their characteristics of compressive strength, elastic modulus and shrinkage for 91 days. The empirical relationship between the mechanical properties of concretes and shrinkage strain was analyzed mathematically. The results indicate that the compressive strength and elastic modulus of concrete are exponentially related the shrinkage strain of concrete. The finding from this study is agreeable with that by Troxell et al [5]. Also, the effectiveness of ACI 209 and CEB-FIP models on predicting the shrinkage behavior of concretes used frequently in Florida was evaluated. The result indicates that CEB-FIP model gives more reliable prediction than ACI 209 model does.

scholarly journals The Effect of the Composition of a Concrete Mixture on Its Volume Changes

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 828
Author(s):  
Martin Ťažký ◽  
Lenka Bodnárová ◽  
Lucia Ťažká ◽  
Rudolf Hela ◽  
Milan Meruňka ◽  
...  
Keyword(s):  
High Temperature ◽  
Fly Ash ◽  
Specific Effect ◽  
Mineralogical Composition ◽  
Point Of View ◽  
Volume Changes ◽  
Granulated Blast Furnace Slag ◽  
Concrete Mixtures ◽  
The Individual ◽  
Mineral Additives

The presented research aims to clarify the specific effect of the individual components of concrete with Portland cement CEM I 42.5 R on the volume changes of concrete. The effect of the filler component was evaluated from the point of view of the composition and type of aggregate (crushed versus mined) and from the point of view of the mineralogical composition of the aggregate. Concrete formulas with a maximum aggregate grain size of 16 and 22 mm were assessed. The effect of the binder component on the shrinkage of the concrete was monitored on the concrete mixtures produced using the same aggregate and maintaining the same strength class of concrete, C 45/55. The effect of the addition of finely ground limestone, finely ground granulated blast furnace slag and coal high-temperature fly ash was monitored. It was found that the maximum aggregate grain and the type of grading curve do not have a significant effect on the volume changes of concrete. Concretes with mined aggregates showed lower shrinkage than concretes with crushed aggregates. The most significant is the effect of the type of aggregate on the volume changes in the first 24 h. Mineral additives have a positive effect on the elimination of the volume changes of concrete, while the addition of high-temperature fly ash proved to be the most suitable.

scholarly journals Estimation of Hydration Degree of Blended Cements with the Help of k-Values

Materials ◽  
2019 ◽  
Vol 12 (15) ◽  
pp. 2420 ◽  
Author(s):  
Reiterman ◽  
Holčapek ◽  
Davidová ◽  
Jaskulski ◽  
Keppert
Keyword(s):  
Portland Cement ◽  
Ceramic Powder ◽  
Numerical Estimation ◽  
Time Intervals ◽  
Blended Cements ◽  
Degree Of Hydration ◽  
Mineral Additives ◽  
Furnace Slag ◽  
Active Mineral Additives

The growing utilization of various mineral additives in the building industry has caused concern worldwide to reduce the emissions of carbon dioxide from Portland cement (OPC) production. The present paper is focused on the determination of the degree of hydration of blended binding systems based on Portland cement. Blast furnace slag, fly ash, and ceramic powder are used in the study; they are applied by 12.5 wt.% up to 50% of OPC replacement. The evolution of the hydration process is monitored using thermogravimetry in selected time intervals to determine the degree of hydration; its ultimate value is obtained from numerical estimation using the Michaelis-Menten equation. However, due to the application of active mineral additives, the correction in terms of equivalent binder is conducted. Corrected values of the degree of hydration exhibit good fit with compressive strength.

Assessing the corrosion performance for concrete mixtures made of blended cements

2018 ◽  
Vol 168 ◽  
pp. 21-30 ◽  
Author(s):  
Mohamed Atef Ibrahim ◽  
Alaa El-Din M. Sharkawi ◽  
Mohamed M. El-Attar ◽  
Osama A. Hodhod
Keyword(s):  
Corrosion Performance ◽  
Blended Cements ◽  
Concrete Mixtures

Scanning Electron Microscopy and x-ray analysis of microparticles and early hydration effects

1995 ◽  
Vol 53 ◽  
pp. 692-693
Author(s):  
Yun Lu ◽  
David C. Joy
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Resolution ◽  
Morphological Development ◽  
Early Hydration ◽  
X Ray ◽  
Blended Cements ◽  
Powder Particles ◽  
Chemical Wastes ◽  
Scanning Electron

High resolution scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDXA) were performed to investigate microparticles in blended cements and their hydration products containing sodium-rich chemical wastes. The physical appearance of powder particles and the morphological development at different hydration stages were characterized by using high resolution SEM Hitachi S-900 and by SEM S-800 with a EDX spectrometer. Microparticles were dispersed on the sample holder and glued by 1% palomino solution. Hydrated bulk samples were dehydrated by acetone and mounted on the holder by silver paste. Both fracture surfaces and flat cutting sections of hydrating samples were prepared and examined. Some specimens were coated with an 3 nm thick Au-Pd or Cr layer to provide good conducting surfaces. For high resolution SEM S-900 observations the accelerating voltage of electrons was 1-2 KeV to protect the electron charging. Microchemical analyses were carried out by S800/EDS equipped with a LINK detector of take-off angle =40°.

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