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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 English-speaking countries as portland blast-furnace (slag) cement.

These prisms contained between 0 and 70% slag cement in combination with portland cements, and had concrete alkali contents between 4.5 and 11 kg/m3 (0.3 and 0.7 lb/ft3). The alkali content of the Portland cements ranged from 0.54 to 1.15% and that of the slag cements from 0.58 to 0.83%.

Jul 27, 2017· Prof. J. Davidovits explains the main differences between AAC (Alkali-Activated Cement or Concrete), AAS (Alkali-Activated Slag), AAF (Alkali-Activated Fly Ash) and Slag-based Geopolymer cement, in terms of chemistry, molecular structure, long-term durability. In a second part, on hand of the industrialization of Slag/fly ash-based geopolymer ...

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 alkali-activated slag concrete and up to 25% for Portland cement concrete.

As a new construction material to mitigate the disadvantages of concrete, fiber-reinforced alkali-activated slag or geopolymer composite is environmentally friendly because it can be produced using industrial byproducts [5,6,7,8,9,10,11]. It also has high ductility, of over 3%, under a tensile load.

Terminology and Specifications - SCIC #12 An excellent primer for those new to the slag cement industry, SCIC #12, Terminology and Specifications, offers definitions of 12 basic slag cement-related terms, including slag cement, granulated blast furnace slag, blended cement, hydraulic cement .

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 alkali-silica reactivity and sulfate ...

The paper discusses approaches to compositional build-up 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 blast-furnace slags, admixtures and additives, compatible with alkali activated cements, water glass and mode of ...

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 provisions for personal protective equipment which are specified in the Materials Safety Data Sheets for many commercially-available alkali-activated 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 ...

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 (1-6).

Jul 07, 2015· Recent interest in creating green construction materials has sparked the development of portland cement–free binders. Alkali-activated slag (AAS) concrete has a low embodied energy and comparable or superior strengths to ordinary portland cement (OPC) concrete.

This study deals with the development of a new binder using alkali-activated ground granulated blast furnace slag (GGBFS) and the fine fraction of non-calcined dredged sediments. The effects of...

This paper presents a characterization analysis of alkali-activated steel slag. The effect ratio of steel slag and ferronickel slag which are the precursor materials on the compressive strength of the alkali-activated materials was investigated. The combination of sodium hydroxide solution of 15 moles concentration and sodium silicate was used as an alkaline activator.

Alkali-activated ground granulated blast-slag (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.

Ground-granulated blast-furnace slag (GGBS or GGBFS) is obtained by quenching molten iron slag (a by-product of iron and steel-making) from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder.

Indeed, geopolymer cement is sometimes mistaken for alkali-activated cement and concrete, developed more than 50 years ago by V.D. Glukhovsky in Ukraine, the former Soviet Union. They were originally known under the names "soil silicate concretes" and "soil cements".

Slag powder processing equipment and technological process. Phrase one: raw material crushing Slag blocks will be crushed to 15mm-50mm fineness by crusher. Phrase two: grinding Crushed slag material will be sent to the storage hopper by the elevator, and then the .

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 (calcium-silicate hydrate or CSH).

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.

Alkali activated slag (AAS) has gained huge attention in recent years due to its ability to replace ordinary Portland cement (OPC) as a binder in concrete. A need to replace OPC is imminent due to the high carbon dioxide emitted into the environment during its production. However, the use of this type of binder did not eliminate the huge strain placed on the deposit of natural resources.

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 slag-blended cement paste through the technologies of X-ray diffraction (XRD), scanning electron microscopy (SEM), and nuclear magnetic resonance spectroscopy (NMR).

Alkali-silica reaction (ASR) is of more concern because aggregates containing reactive silica materials are more common. In ASR, aggregates containing certain forms of silica will react with alkali hydroxide in concrete to form a gel that swells as it adsorbs water from the surrounding cement .

Thus, at 60 C the slag with 640 mý/kg of fineness and a water-cement ratio of 0.33 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.
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