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Rossi, E. (author), Nijland, T.G. (author), Copuroglu, O. (author), Polder, R.B. (author), Savija, B. (author)
Although corrosion of reinforcement is a well-known issue for the construction industry, there are still open questions about some fundamentals of corrosion in reinforced concrete. These points include, among others, which are the most sensitive locations of the steel/concrete interface for pitting corrosion to initiate and to propagate. In this...
conference paper 2019
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Pereira, L.F. (author), Weerheijm, J. (author), Sluys, L.J. (author)
Although many aspects of the fracturing process of concrete are now well understood and successfully simulated with various models, it is still very difficult to properly simulate the different failure mechanisms observed in a concrete structure induced by ballistic impact. In this paper, an enhanced version of the effective-rate-dependent...
article 2018
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Souza, L.M.S. (author), Polder, R.B. (author), Çopuroğlu, O. (author)
Alkali–silica reaction (ASR) affects numerous concrete structures worldwide. However, the intervention options for ASR in existing structures are limited. Lithium is proposed to suppress expansion. In this paper, an investigation on two-chamber lithium migration as treatment against ASR is presented. First, the influence of different levels of...
article 2017
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Yang, Z. (author), Polder, R. (author), Mol, J.M.C. (author)
Owing to the unique molecular structure and high ion exchange capacity, hydrotalcites are believed to have a potential to be modified and tailor-made as an active corrosion protective component of reinforced concrete. In this paper, two types of modified hydrotalcites (MHT-pAB and MHT-NO2) were tested both in alkaline solution and mortar for...
article 2017
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Pacheco, J. (author), Polder, R.B. (author)
Chloride induced reinforcement corrosion is the predominant degradation mechanism
article 2016
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Pereira, L.F. (author), Weerheijm, J. (author), Sluys, L.J. (author)
The development of realistic numerical tools to efficiently model the response of concrete structures subjected to close-in detonations and high velocity impact has been one of the major quests in defense research. Under these loading conditions, quasi-brittle materials undergo a multitude of failure (damage) mechanisms. Dynamic tensile failure ...
article 2016
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Vegt, I. (author)
Concrete is commonly used in protective and civil structures, like tunnels and storage buildings. For the design and reliable safety assessment of such structures it is very important to know the behaviour of concrete under static loading conditions as well as under impulsive loading. To understand the behaviour of concrete under impulsive...
doctoral thesis 2016
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Vegt, I. (author), Weerheijm, J. (author)
The mechanical response of concrete is represented in the load-deformation curve which shows the response up to maximum strength as well as the post-peak response up to complete failure. Dynamic tests exhibit an extensive rate effect on the tensile strength beyond loading rates of about 50 GPa/s (strain rates > 1/s). Whether the apparent...
conference paper 2015
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Pereira, L. (author), Weerheijm, J. (author), Sluys, L.J. (author)
The development of realistic numerical tools to efficiently model the response of concrete structures subjected to close-in detonations and high velocity impacts has been one of the major quests in defense research. Under these loading conditions, quasi-brittle materials undergo a multitude of failure (damage) mechanisms. Dynamic tensile failure...
conference paper 2015
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Pacheco, J. (author), Šavija, B. (author), Schlangen, E. (author), Polder, R.B. (author)
The durability of cracked reinforced concrete is a serious concern in the construction industry. Cracks represent fast routes for chloride penetration, which can result in reinforcement corrosion. Bending or tapered cracks have the characteristic of being wider at the surface and becoming narrower towards the reinforcement. In reinforced...
article 2014
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Lu, Y. (author), Xu, J. (author), Weerheijm, J. (author)
This paper presents a numerical modelling study on the simulation of the cracking process and fracture energy in concrete under high strain rate. To capture the stress wave effect and the damage evolution at the meso-length scale, both a homogeneous model with a millimetre-resolution mesh and an explicit heterogeneous mesoscale model with random...
conference paper 2013
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Caspeele, R. (author), Sykora, M. (author), Allaix, D.L. (author), Steenbergen, R.D.J.M. (author)
In contrast to the design of new structures, the assessment of existing structures often relies on the subjective judgement of the investigating engineer. An objective verification format for existing structures based on alternative partial factors is however feasible, enabling a rather simple and straightforward, but objective and coherent...
article 2013
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Ožbolt, J. (author), Weerheijm, J. (author), Sharma, A. (author)
The behavior of concrete structures is strongly influenced by the loading rate. Compared to quasi-static loading, on meso and macro-scale concrete loaded by impact loading acts in a different way. First, there is a strain-rate influence on strength, stiffness, ductility, and, second, there are inertia forces activated which influence the...
conference paper 2013
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Agar-Ozbek, A.S. (author), Weerheijm, J. (author), Schlangen, E. (author), van Breugel, K. (author)
In this study, an experimental configuration that reveals the dynamic response of porous concretes in a drop weight impact test was introduced. Through the measurement of particle velocity at the interface, between the impactor and the concrete target, the dynamic response was obtained in an easily applicable way. Laser Doppler velocimetry (LDV)...
article 2012
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Weerheijm, J. (author), Vegt, I. (author)
Data on the dynamic fracture energy of concrete are scarce and also not consistent due to different test methods, data analyses and definitions. In [1] the authors summarized and evaluated the test methods. Suggestions for the standardization of dynamic tensile testing were given. In the current paper the discussion is continued. First,...
conference paper 2011
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Varas, J.M. (author), Soetens, F. (author)
The effect of a blast explosion on a typical steel frame building is investigated by means of computer simulations. The simulations help to identify possible hot spots that may lead to local or global failure. The blast energy is transferred to the structure by means of the façade. In particular attention is paid to the modelling of the façade...
conference paper 2010
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Nijland, T.G. (author), Larbi, J.A. (author), TNO Bouw en Ondergrond (author)
Concrete petrography is the integrated microscopic and mesoscale (hand specimen size) investigation of hardened concrete, that can provide information on the composition of concrete, the original relationships between the concrete's various constituents, and any changes therein, whether as a result of ageing or damage processes. Concrete...
bookPart 2010
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Peelen, W.H.A. (author), Vervuurt, A.H.J.M. (author), TNO Bouw en Ondergrond (author)
Fire safety of buildings and structures is an important issue, and has a great impact on human life and economy. One of the processes negatively affecting the strength of a concrete building or structure during fire is spalling. Many examples exists in which spalling of concrete during fire has caused severe damage to structures, such as in the...
article 2008
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Polder, R.B. (author), de Rooij, M.R. (author), TNO Bouw en Ondergrond (author)
This article presents a series of investigations on six concrete structures along the North Sea coast in The Netherlands. They had ages between 18 and 41 years and most of them were made using Blast Furnace Slag cement. Visual inspections showed corrosion damage in only one structure, related to relatively low cover depths. All structures showed...
article 2005
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Siemes, A.J.M. (author), TNO Bouw (author)
After the introduction of reinforced concrete it was believed that the material was extremely durable. Soon it was found that reinforced concrete could have serious durability problems and that special care should be taken to avoid them. Durability became a design issue.
conference paper 2002
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