Classification of cements

Table 8. ISO Classification of Cemented Carbide Tools According to Use ...

Before proceeding further it is well to consider the term cement, for its definition can be the source of some confusion. Both the Oxford English Dictionary and Webster give two alternative definitions. One defines a cement as a paste, prepared by mixing a powder with water, that sets to a hard mass. In the other a cement is described as a bonding agent. These two definitions are quite different. The first leads to a classification of cements in terms of the setting process, while the second lays emphasis on a property. In this book the term cement follows the sense of the first of these definitions. 

In the European standards, above all inEN 197-1, another principle was adopted, dividing cement on kinds according to the quantity and kind of mineral additions. However, the division on class is common, independently of cement kind. These rules of division facilitate the classification of cements for concrete production, designated for constractions exploiting in different expositions. 

The following classification of cement mineral additions is commonly accepted ... 

The definitions and classifications of cement and concrete-like composite materials presented below are used in the chapters that follow. Various authors have put forward slightly different definitions and classifications, which can be found in Hannant (1978), Venuat (1984), Mindess et al. (2003), and others. This variety is not surprising, because concrete-like composites are produced in the largest mass and volume of any building materials in the world. They are applied in different structural and non-structural elements and are made with various constituents, used in different combinations. The term concrete-like composites is somewhat wider than cement-based composites. In fact, in this chapter a few materials are mentioned which do not contain any kind of cement and in which other binders are applied. 

Classification of cements can be based on various sets of criteria. Thus, the principal distinctive characteristics may be ... 

Certain treatment systems fall in the category of cement-pozzolanic processes and have been in use for some time outside the U.S. In these systems, both cement and lime-siliceous materials are used in combination to give the best and most economical containment for the specific waste being treated In general, the bulk of the comments (under both classifications above) hold for techniques using a combination of treatment materials. 

The classification of Lewis acids and bases relevant to AB cements is shown below. 

See also Iron entries hydration, 5 477-478 in Portland cement, 5 467 in Portland cement clinker, 5 473t classification of, 11 55-58 crystal chemistry of, 11 59-71 defined, 11 55 energy losses in, 11 64-66 physical properties of, 11 59-71 processing of, 11 71-75 properties of spinel and M-type,... 

Wood well treated with current commercial fire-retardant impregnation treatments will have flame-spread ratings of 25 or less. Many treated wood products have obtained a special marking or designation "FR-S" from UL (36) for having a flame-spread, fuel-contributed, and smoke-developed classification of not over 25 and no evidence of significant progressive combustion in an extended 30-minute ASTM E84 (34) test procedure. The fuel-contributed and smoke-developed classifications are also calculated relative to performance of red oak and asbestos-cement board. 

Table 4.3 Classification of silcrete according to matrix (cement) type and macromorphology (Wopfner, 1978,1983)... 

Classification of silcrete according to matrix (cement) type and macromorphology. 

With respect to corrosion, the conventional classification of climates in marine, inland, industrial, etc. types is not sufficient. It should now be specified with respect to the actual chemical components in the atmosphere, as well as humidity and other factors. Recent research in this field has led to much more precise methods for estimating corrosion rates in polluted atmospheres (38). Economically, perhaps even more important problems are caused by the increased corrosion of water supply pipelines. Not only copper is dissolved, but also cadmium from soldered joints, and larger steel and cement pipelines may also be affected. 

Late cements causing post-dissolution porosity reduction include minor kaolinite and late ferroan calcite. Late ferroan dolomite is an important cement in all porous sandstones of the 0-35 well, where it reduced porosity by 4.2% on average (ranging from trace amounts to 20%). In the diage-netic maturity classification of Schmidt MacDonald (1979a) the Catalina Sandstone is semimature. 

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