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Polder, R.B. (author), Nijland, T.G. (author), de Rooij, M.R. (author), Larsen, C.K. (author), Pedersen, B. (author)
road environment in The Netherlands for nearly a century. The experience is good and structures with long service lives can be obtained, as has been shown by several field studies. This is caused by a high resistance against chloride penetration and a high electrical resistivity, demonstrated both in the field and in the laboratory. Due to the...
conference paper 2014
document
de Rooij, M.R. (author), Godart, B. (author)
Alkali-aggregate reaction in concrete is the name given to a group of reactions leading to expansion caused by a chemical reaction between the alkalis contained in the cement paste and certain reactive forms of (usually silica containing) minerals in the aggregates, see Figure 4.The alkalis in the pore solution are derived from the hydration of...
bookPart 2013
document
de Rooij, M.R. (author)
bookPart 2013
document
de Rooij, M.R. (author), Godart, B. (author)
For any existing structure, a routine inspection is ordinarily a starting point of a cyclic process to maintain the safety and reliability of the structure (Figure 9). It is part of an inspection process where detailed inspection and in depth investigation are important actions. This chapter covers review of existing records, field equipment and...
bookPart 2013
document
de Rooij, M.R. (author), Godart, B. (author)
bookPart 2013
document
de Rooij, M.R. (author), Godart, B. (author)
From the confirmation inspection and its subsequent test results the presence of AAR has either been confirmed or eliminated. Assuming the first outcome, the next step is to investigate the severity of the situation, see Figure 23. One should keep in mind that it is possible that some evidence of AAR may be found in concrete where siliceous...
bookPart 2013
document
de Rooij, M.R. (author)
When routine inspection results, like examples given in the previous chapter, show indications which could point in the direction of AAR, it is a wise decision to bring in the specialists. As these specialists are normally brought in when something odd has been observed, the first step to be taken is to establish what the cause of the “strange”...
bookPart 2013
document
de Rooij, M.R. (author), Godart, B. (author)
Diagnosis of damage to concrete in structures caused by Alkali-Aggregate Reaction (AAR) often involves complex processes because of the resemblance of the external characteristics of the damage with those caused by other actions, such as e.g. frost attack or shrinkage. The wide variety of aggregate types used in concrete worldwide, the different...
bookPart 2013
document
de Rooij, M.R. (author), Polder, R.B. (author), TNO Bouw (author)
Nowadays important concrete infrastructure is increasingly being designed for long service life by modelling of degradation and probabilistic assessment of uncertainties, e.g. using the DuraCrete method. Although on paper a reliable and durable structure will result, it is the execution phase that can make or break the service life approach....
conference paper 2007
document
Nijland, T.G. (author), Larbi, J.A. (author), van Hees, R.P.J. (author), Lubelli, B.A. (author), de Rooij, M.R. (author), TNO Bouw (author)
A microscopic survey of over 1000 of samples of concrete and masonry mortars from structures in the Netherlands shows that, in practice, self healing occurs in historic lime and lime – puzzolana mortars, in contrast to modern cement bound concretes and mortars. Self healing may be effected by the formation of either new Ca-carbonate, CaCO3, or...
conference paper 2007
document
de Rooij, M.R. (author), TNO Bouw en Ondergrond (author)
Many walls of ancient buildings are covered with plaster layers. Amongst the most recurrent causes of damage of plasters and substrates are moisture and salt decay processes. To combat these salt problems, special salt resistant plasters have been developed for application on salt loaded substrates. However, experience in the field has shown...
article 2006
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