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This paper presents a characterization analysis of alkaliactivated steel slag. The effect ratio of steel slag and ferronickel slag which are the precursor materials on the compressive strength of the alkaliactivated materials was investigated. The combination of sodium hydroxide solution of 15 moles concentration and sodium silicate was used as an alkaline activator.
Blast furnace slag cement is the mixture of ordinary Portland cement and fine granulated blast furnace slag obtained as a by product in the manufacture of steel with percent under 70% to that of cement. Ground granulated blast furnace slag cement (GGBFS) is a fine glassy granules which contain cementatious properties.
The NewCem® Slag Cement Advantage. To produce quality slag, a producer needs to have slag with an ideal chemistry from a consistent source and needs to have equipment close to the slag source to provide rapid quenching of the slag. Lafarge engineers and scientists have led North America in the research and development of specifications for slag.
This test method provides a means for evaluating the ability of pozzolans and ground granulated blastfurnace slag to control deleterious internal expansion due to alkalisilica reaction when used with an aggregate intended for use in concrete.
Cement Cement Slag cements: The granulated slag made by the rapid chilling of suitable molten slags from blast furnaces forms the basis of another group of constructional cements. A mixture of portland cement and granulated slag, containing up to 65 percent slag, is known in the Englishspeaking countries as portland blastfurnace (slag) cement.
Alkali Content of Concrete Mix Water and Aggregates Introduction Alkali silica reaction (ASR) is a chemical reaction between some types of aggregate and the highly alkaline pore water present in all Portland cement concretes. When the concrete contains sufficient moisture, alkalis and reactive aggregate the reaction produces
Jul 07, 2015· Recent interest in creating green construction materials has sparked the development of portland cement–free binders. Alkaliactivated slag (AAS) concrete has a low embodied energy and comparable or superior strengths to ordinary portland cement (OPC) concrete.
SCIC #23, Slag Cement and Life Cycle Prediction Models, examines how slag cement can positively affect some of the properties that increase the useful life of a concrete structure and decrease life cycle cost, including low permeability, increased corrosion resistance, high strength, improved resistance to alkalisilica reactivity and sulfate ...
Blastfurnace slag cement with different slag content (48%, 63% and 78%) and two different strength classes (32,5 and 42,5) were used. Table 1 shows the chemical composition and Table 2 the most important physical properties. Silica fume was used in form of a slurry with a water content of 50%.
Alkaliactivation kinetics of phosphorus slag cement using compressive strength data Ceramics – Silikáty 59 (3) 250260 (2015) 251 3) an accurate measurement of the amount of products and nonreacted materials in specified time intervals is difficult, can be addressed. Owing to these constraints, researchers consider the
Thus, at 60 C the slag with 640 mý/kg of fineness and a watercement ratio of reached a compressive strength of approximately 40 MPa after a curing period of 4 hr. After a curing period of 72 hr, the heat of hydration of the slag cements was only about 60 percent of that of the modified portland cement.
The paper discusses approaches to compositional buildup of high strength alkali activated cements made using water glass as alkaline activator represented by commercial products in a form of powder and liquid. The purpose was to study the influence of fineness of ground granulated blastfurnace slags, admixtures and additives, compatible with alkali activated cements, water glass and mode of ...
An alternative approach is alkaline activation of slag by group I metal alkalis. Compared with ordinary Portland cement (OPC) and interground slag blended cement, alkali activated slag (AAS) cement has some advantageous properties, including rapid and high strength development, good durability and high resistance to chemical attack (16).
The provisions for personal protective equipment which are specified in the Materials Safety Data Sheets for many commerciallyavailable alkaliactivated binder systems and concretes are actually very similar to those specified for the handling of fresh Portland cement paste and concrete; the importance of correctly following the required ...
Alkaliactivated ground granulated blastslag (AAS) is the most obvious alternative material for ordinary Portland cement (OPC). However, to use it as a structural material requires the assessment and verification of its durability. The most important factor for a durability evaluation is the degree of carbonation resistance, and AAS is known to show lower performance than OPC.
Groundgranulated blastfurnace slag (GGBS or GGBFS) is obtained by quenching molten iron slag (a byproduct of iron and steelmaking) from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder.
This study deals with the development of a new binder using alkaliactivated ground granulated blast furnace slag (GGBFS) and the fine fraction of noncalcined dredged sediments. The effects of...
Sep 09, 2017· Successive addition of sodium hydroxide deteriorates the mechanical strength of the slag cement. The reaction kinetics are also studied by examining the hydration products of slagblended cement paste through the technologies of Xray diffraction (XRD), scanning electron microscopy (SEM), and nuclear magnetic resonance spectroscopy (NMR).
These prisms contained between 0 and 70% slag cement in combination with portland cements, and had concrete alkali contents between and 11 kg/m3 ( and lb/ft3). The alkali content of the Portland cements ranged from to % and that of the slag cements from to %.
This paper examines on the setting time and mechanical strength behaviour of slag cement pastes activated with different alkaline activators. For this purpose three alkaline solutions were used: waterglass solution (27% SiO2, 18 % Na2O and 55% H2O), NaOH and Na2CO3, maintaining always a constant concentration of Na2O (4% by mass of slag).
In this standard practice, the minimum level of slag is determined by consideration of aggregate reactivity, alkali availability, the exposure conditions, and the size and type of the concrete structure. Slag cement contains a small amount of, the amount of alkali is similar to that of low tomoderatealkali portland cement ...
Slag powder processing equipment and technological process. Phrase one: raw material crushing Slag blocks will be crushed to 15mm50mm fineness by crusher. Phrase two: grinding Crushed slag material will be sent to the storage hopper by the elevator, and then the .
The granulated slag is then dried and ground in a ball mill or similar equipment to fineness similar to normal Portland cement or greater ... After 12 months of exposure to the Na 2 SO 4 solution, the strength decrease was up to 17% for alkaliactivated slag concrete and up to 25% for Portland cement concrete.
Slag cement improves many of the strength and durability properties of hardened concrete. Slag cement is a hydraulic binder that, like portland cement, reacts with water to form cementitious material (calciumsilicate hydrate or CSH).
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