Concrete and aggregate specifications
Specification of freeze-thaw resistant concrete is exemplified by European practice outlined in the primary specification documents for concrete and aggregates […]
The purpose of this book is to bring together a series of reviews on topics of current relevance to the durability of concrete and cement-based composites. One might reasonably ask why such a book is now believed to be needed as concrete and related materials have been used with outstanding success in major construction projects for well over two thousand years. Indeed numerous ancient concrete structures, such as the Pantheon in Rome, and masonry structures with mortar joints, such as the Pont du Gard Aqueduct near NõÃmes in southern France (see Fig. 1.1), have survived to the present day in excellent states of preserva- tion. These and other examples of Roman construction works incorporating hydraulic cements made from lime and volcanic earth (or similar vitrified alumino-silicates, known collectively as pozzolanas, after Pozzuoli near Naples where a natural source of such material exists) have shown remarkable dur- ability even where they have been exposed to damp, aggressive environments. An impressive illustration was provided by Davey (1974) whose photograph of part of a Roman breakwater that had been exposed to the sea near Naples for two millennia (reproduced in Fig. 1.2), demonstrates that the mortar joints had endured far more successfully than the now heavily eroded stone blocks which they had been connecting.
Specification of freeze-thaw resistant concrete is exemplified by European practice outlined in the primary specification documents for concrete and aggregates […]
The prescriptive approach to durability in EN 206-1 maintains the durability grade principle of Deacon and Dewar (1982) that underpins
Concrete and aggregate Specification issues in Standard EN 206-1 Read Post »
Chemical attack on concrete is a rather complicated subject since the chemistry of concrete itself is complex and the material
It follows from the above considerations that there is no unique threshold proportion of chloride contamination that applies generally and,
As far as new reinforced concrete structures are concerned, most modern codes of practice have adopted strict limits on maximum
A wide range of products and systems are available and may be classified as pore liners, pore blockers and coatings
Characteristics of paints and polymeric surface treatments for concrete Read Post »
A number of subject specific terms are useful in order to discuss concisely frc structure and behaviour. The term frc
Since passivity represents the principal mechanism by which steel is protected from corrosion in concrete, it is necessary to consider the
As noted previously, the reactions between atmospheric CO2 and alkaline components of concrete produce a carbonated surface layer in which