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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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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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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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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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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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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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Polder, R.B. (author)
This paper describes methods to assess concrete resistivity on site for various purposes related to corrosion and protection of reinforcement. It is based on a first draft of a RILEM Technical Recommendation. The electrical resistivity of concrete can be related to the two processes involved in corrosion of reinforcement: initiation (chloride...
conference paper 2000
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Polder, R.B. (author), de Vries, H. (author), TNO Bouw (author)
Penetration of de-icing salts into concrete bridge decks may cause corrosion of reinforcement. Hydrophobic treatment of concrete was studied as additional protection. It was shown that hydrophobic treatment strongly reduces chloride ingress, during semi-permanent contact and in wetting/drying situations. The protection remains effective for at...
conference paper 1999
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de Vries, J. (author), Polder, R.B. (author), Borsje, H. (author), TNO Bouw (author)
The subject of this study was the performance of hydrophobic treatment to protect concrete against chloride penetration from de-icing salts. Hydrophobic treatment makes a concrete surface absorb less water and less chloride. Several types of tests were carried out to study the performance of hydrophobised concrete. Salt ponding/drying tests...
conference paper 1998
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Polder, R.B. (author), Bakker, J.D. (author), Postema, F.J. (author), TNO Bouw (author)
As a case study, the cost of applying cathodic protection (CP) to the columns and beams supporting two bridges was compared to the cost of replacement (due to reinforcement corrosion). All costs during the service life of the CP system were considered: initial cost, annual checks, maintenance of anode systems and specialist supervision. It was...
conference paper 1998
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Polder, R.B. (author), Nerland, O.C. (author), TNO Bouw (author)
An experimental study of cathodic protection (CP) was carried out with a conductive primer anode applied to specimens from a concrete bridge. The bridge was demolished after 30 years of service due to severe delaminations and reinforcement corrosion. Four specimens of approximately 1 m2 each were made and characterised by steel potential,...
conference paper 1998
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de Vries, J. (author), Polder, R.B. (author), Borsje, H. (author)
Hydrophobic treatment makes a concrete surface absorb less water and less chloride. Hydrophobic treatment was studied as a protection agninst chloride penetration from deicing salts. Test methods were designed. Nine hydrophobic products were tested, of which three complied to the requirements on finished concrete surfaces. The water absorption...
conference paper 1996
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