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Stroeven, P. (author)
Paper reports on experiments performed in the low-cycle compression fatigue domain, considering two relatively high upper load levels and several lower ones. Two frequency levels were emphasized, i.e. 17.5 Hz and 0.175 Hz. An overview is given of characteristics of mechanical behaviour and of the state of damage close to fracture. Particular...
journal article 2010
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Fennis, S.A.A.M. (author)
The goal of this research project on Ecological Concrete was to reduce the CO2-emission of concrete and to reuse secondary materials form concrete production and other industries simultaneously. This also minimizes the use of natural resources and the production costs. To replace cement in concrete in a safe way, the main question answered in...
doctoral thesis 2011
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Schipper, H.R. (author)
В современных архитектурных решениях широко используется криволинейность свободных форм. Именно поэтому изогнутые элементы из сборного бетона могут быть потенциальным рын- ком для производителей. В прошлом не существовало просто- го способа для производства таких компонентов. Исследования, проводимые в докторантуре Дельфтского Технического...
journal article 2011
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Wiktor, V.A.C. (author), Jonkers, H.M. (author)
conference paper 2011
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Stroeven, P. (author), Huan, H. (author)
The paper focuses on the quality of predicting the damage characteristics of the loaded engineering structure by subjecting section images of cores supposedly drawn from the concrete of the structure to quantitative image analysis by sweeping test lines. Automation of this data acquisition stage is shown, generally leading to information that is...
conference paper 2011
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Wiktor, V. (author), Jonkers, H.M. (author)
La formation d’un réseau continu de fissures contribue à l’augmentation de la perméabilité du béton, réduisant ainsi de manière importante sa résistance à l’attaque d’agents agressifs dissous dans l’eau. Afin d’augmenter la capacité de cicatrisation autogène du béton, certains agents cicatrisants spécifiques peuvent être incorporés dans la...
journal article 2011
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Stroeven, P. (author), Le, N.L.B. (author), Stroeven, M. (author), Sluys, L.J. (author)
The paper introduces a novel approach to porosimetry in virtual concrete, denoted as random node structuring (RNS). The fresh state of this particulate material is produced by the DEM system HADES. Hydration simulation is a hybrid approach making use of wellknown discretization and vector methods. Particle interferences (overlap) in the dynamic...
conference paper 2011
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Grünewald, S. (author), Janssen, B. (author), Schipper, H.R. (author), Vollers, K.J. (author), Walraven, J.C. (author)
This paper discusses the effect of intentional deformation of a flexible formwork after casting of the concrete and the influence of the characteristics of concrete in the fresh state on the quality of a concrete element. This deformation is intended to bring the concrete element in its desired final shape; the deformation typically takes place...
conference paper 2012
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Stroeven, P. (author), He, H. (author)
This paper presents some evidence of the impact of the Brazil nut effect (BNE) on concrete’s particulate structure on meso-level (aggregate) as well as on micro-level (cement paste). BNE is associated with long-range size segregation in particle mixtures due to vibration in slurry state of concrete, both near boundaries and in bulk. Presented...
journal article 2012
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He, H. (author), Le, N.L.B. (author), Stroeven, P. (author)
Experimental approaches in concrete technology are time-consuming, laborious and thus expensive. Developments in computer facilities render possible nowadays realistically simulating the particulate structure and microstructure of cementitious materials. For that purpose, discrete element methods (DEM) are required because of more correctly...
journal article 2012
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Fennis, S.A.A.M. (author), Walraven, J.C. (author)
The annual production of Portland cement, estimated at 3.4 billion tons in 2011, is responsible for about 7% of the total worldwide CO2-emission. To reduce this environmental impact it is important to use innovative technologies for the design of concrete structures and mixtures. In this paper, it is shown how particle packing technology can be...
journal article 2012
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Huan He, H. (author), Le, N.L.B. (author), Stroeven, P. (author)
Durability of concrete in engineering structures is becoming more and more of a major problem. Research into such problems is complicated and expensive, however. Developments in computer technology make it possible nowadays realistically simulating cementitious materials and studying its pore network structure. In this paper use is made of the...
journal article 2012
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Polder, R.B. (author)
A review is given of research on the durability performance of concrete made with blast furnace slag and fly ash related to chloride induced reinforcement corrosion, carried out in the Netherlands, where slag has been used in cement for almost a century. Results are presented from field studies on concrete in marine environment and laboratory...
journal article 2012
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Stroeven, P. (author), He, H. (author), Le, L.B.N. (author)
Realistic simulation of particulate materials like concrete on meso- as well as micro-level is nowadays possible by fast developments in computer technology. This would be a more economic way than by physical experiinents, which are more time-consuming, laborious and thus expensive. This concern the production of the aggregate structure or of...
conference paper 2012
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Schlangen, H.E.J.G. (author), Sangadji, S. (author)
Infrastructures cover a very broad spectrum of different materials. This paper focuses on civil engineering structures, concrete and asphalt in particular. The public demand for such infrastructures is high level of service and performance, high durability and minimum negative ecological impact. New emerging self healing materials science...
journal article 2013
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Stroeven, P. (author), He, H. (author)
Loose random and dense random mono-size pacl<ing states were investigated by the discrete element modelling (DEM) for eight types of polyhedral grains, for ellipses with different aspect ratio, for cubes and for spheres. Focus was on density, sphericity of the grains and average value and frequency distribution of coordination number. The 3D...
conference paper 2013
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Slobbe, A.T. (author), Hendriks, M.A.N. (author), Rots, J.G. (author)
This paper presents a dedicated numerical test that enables to assess the directional mesh bias of constitutive models in a systematic way. The test makes use of periodic boundary conditions, by which strain localization can be analyzed for different mesh alignments with preservation of mesh uniformity and with exclusion of boundary disturbances...
conference paper 2013
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Weerheijm, J. (author), Sharma, A. (author), Ozbolt, J. (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), Lu, Y. (author), Xu, 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 millimetreresolution mesh and an explicit heterogeneous mesoscale model with random...
conference paper 2013
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Mors, R.M. (author), Jonkers, H.M. (author)
A functional experimental concrete system has been developed in our lab, in which a two component bacteria-based healing agent contained in a protective reservoir is included in the concrete mixture. Incorporated bacteria have the potential to produce copious amounts of calcium carbonate based crystals from supplied mineral precursor compounds....
conference paper 2013
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