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Polder, R.B. (author)
Lezing gehouden voor de VABOR ledenvergadering op 7 december 1995 door Dr. Rob B. Polder van TNO Bouw, te Rijswijk. Hij is lid van CUR commissie B 47, Kathodische bescherming van beton en rapporteur van de Aanbeveling die hierover in voorbereiding is. Omdat in mei 1993 over principes en praktische details al een lezing is gehouden (zie VABOR...
article 1996
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Polder, R.B. (author)
Beton is een goedkoop en flexibel bouw-materiaal dat bovendien duurzaam is. Gebruiksduren van 50 tot 100 jaar en meer zijn normaal. Er is maar een klein aantal bedreigingen voor de duurzaamheid. Corrosie van de wapening is verreweg de belangrijkste. Hierover is enige tijd geleden een uitgave verschenen van het NCC [17. In dit artikel belicht Rob...
article 1996
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de Vries, J. (author), Polder, R.B. (author), Borsje, H. (author), TNO Bouw (author)
De Bouwdienst Rijkswaterstaat heeft onlangs het eindrapport gepresenteerd van een onderzoek naar het hydrofoberen van beton. Nagegaan is welk effect hydrofoberen heeft op chioride-indringing, corrosie van de wapening en vorstbestendig held. Het door TNO-Bouw verrichte onderzoek heeft tevens geleid tot het opstellen van prestatie-eisen en een...
article 1996
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Polder, R.B. (author)
Reeds eerder is in Cement over kathodische bescherming gepubliceerd [1. 2]. Sinds de eerste toepassing in 1987 is in de praktijk ruime ervaring opgedaan en is laboratoriumon-derzoek uitgevoerd [3]. Die ervaring is door CUR-commissie B47 bijeengebracht en vast-gelegd in CUR-Aanbeveling 45. die bij dit nummer van Cement is gevoegd. In dit artikel...
article 1996
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Polder, Rob B. (author), Larbi, Joe A. (author), TNO Bouw (author)
TNO Building and Construction Research investigated reinforced concrete prisms submerged in the North Sea for 16 years. The aim was to examine the effects of this potentially aggressive environment on the mechanical properties and the durability of reinforced concrete. It was found that (deep) sea does not constitute a severe environment for...
article 1996
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Polder, R.B. (author), Stoop, B.T.J. (author), TNO Bouw (author)
Kathodische bescherming (afgekort KB) is een moderne techniek om corrosie van wapening in betonconstructies te bestrijden. KB is al op ongeveer 20 gebouwen in Nederland met succes toegepast; het eerste projekt op een brug van Rijkswaterstaat is in 1996 uitgevoerd en een tweede in 1997. In september 1996 is CUR-Aanbeveling 45 "Kathodische...
conference paper 1998
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Polder, R.B. (author), TNO Bouw (author)
Kathodische bescherming (afgekort KB) is een moderne techniek om corrosie van wapening in betonconstructies te bestrijden. KB is in Nederland op meer dan 20 gebouwen en op zeven kunstwerken toegepast. Sinds 1996 bestaat CUR Aanbeveling 45 "Kathodische bescherming van beton", die is opgesteld op grond van ervaringen van betrokken bedrijven en...
conference paper 1999
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Polder, R.B. (author), de Vries, J. (author)
report 2000
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Polder, R.B. (author), Gulikers, J.J. (author), TNO Bouw (author)
article 2001
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Polder, R.B. (author), Borsje, H. (author), de Vries, H. (author), TNO Bouw (author)
Corrosion of reinforcement in concrete bridge decks may occur due to penetration of de-icing salts, even in the presence of an asphalt overlay. This paper reports a laboratory study into additional protection of concrete by hydrophobic treatment. It was found that hydrophobic treatment strongly reduces chloride ingress, both during semi...
article 2001
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Polder, R.B. (author), Nijland, T.G. (author), Peelen, W.H.A. (author), Bertolini, L. (author), TNO Bouw (author)
Cathodic protection has proven to be a reliable and economic method to stop corrosion in reinforced concrete structures. Many systems with activated titanium mesh anode embedded in cementitious mortar have functioned for more than 10 years. The service life depends on the anode/overlay system, which may be determined mainly by acid production...
conference paper 2002
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Polder, R.B. (author), Peelen, W.H.A. (author), TNO Bouw (author)
Concrete prisms were made with four cement types including cements with fly ash and/or blast furnace slag and three waterto- cement (w/c) ratios. Chloride penetration and corrosion of rebars were stimulated by subjecting prisms to cyclic loading with salt solution and drying. Concrete resistivity, steel potentials and corrosion rates were...
article 2002
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Polder, R.B. (author), van den Hondel, A.W.M. (author), TNO Bouw (author)
Chloride extraction of concrete is a short-term electrochemical treatment against corrosion of reinforcing steel. The aim is to remove chloride ions from the concrete cover in order to reinstate passive behaviour. Physically sound concrete is left in place. To make this method more predictable and reliable, a laboratory study was carried out....
article 2002
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Gaal, G.C.M. (author), Polder, R.B. (author), Walraven, J.C. (author), van der Veen, C. (author), TNO Bouw (author)
Deterioration of concrete structures has become an important issue over the last decade. The most fre-quently observed form of deterioration is chloride-initiated corrosion of the reinforcement. Corrosion is initiated when the chloride content at the reinforcement exceeds the critical or threshold chloride content. However the threshold values...
conference paper 2003
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de Rooij, M.R. (author), Polder, R.B. (author)
For effective design for durability and maintenance, knowledge of the penetration process of chloride into concrete is of paramount importance. Such knowledge is important for accurate modelling of the time to initiation of reinforcement corrosion. In this paper the acquisition of model parameters for chloride penetration based on chloride...
conference paper 2003
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Polder, R.B. (author), Peelen, W.H.A. (author), Schuten, G. (author), TNO Bouw (author)
Samples were studied of conductive coatings that had served as anode material in concrete cathodic protection (CP) systems in Norway and The Netherlands for up to about 9 years. Techniques used were light microscopy and scanning electron microscopy (SEM), carried out on thin section samples of about 25 μm thickness. Observation of the coating...
article 2003
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Polder, R.B. (author), TNO Bouw en Ondergrond (author)
article 2005
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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
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Polder, R.B. (author), Larbi, J.A. (author), TNO Bouw en Ondergrond (author)
Explosive spalling of pieces of concrete from the heated surface is considered to be the most dangerous effect of damage of concrete subjected to intense fire attack, especially when it occurs in restricted areas such as underground tunnels. Recent investigations have revealed that the amount of explosive spalling and the extent of cracking can...
article 2007
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Martínez, I. (author), Andrade, C. (author), Vennesland, O. (author), Evensen, U. (author), Polder, R.B. (author), Leggedor, J. (author), TNO Bouw en Ondergrond (author)
It is well known that cathodic protection is the most useful method for stopping corrosion when the deterioration process has started, but the most important issue that is still missing in the cathodic protection studies is how to check its efficiency in a reliable way. This paper presents results of the protection efficiency obtained in...
article 2007
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