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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
document
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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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), 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
document
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), 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.A.C. (author), Jonkers, H.M. (author)
conference paper 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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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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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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Schipper, H.R. (author)
Due to the complexity of the freeform shapes it is often not possible to distinguish any repetitive elements in freeform buildings at all. Most freeform building designs consist of many single or double curved surfaces which require complex shapes for the mould and element edges. Since the costs of the moulds (formwork) for precast concrete make...
conference paper 2010
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Schipper, H.R. (author), Vambersky, J.N.J.A. (author)
The manufacturing of double curved precast concrete elements is still expensive, due to the high costs and limited possibilities for repetitive use of the molds or formwork. The goal of a PhD project recently initiated at TU Delft is to develop a production method that overcomes these difficulties by enabling the mold to be used many times and...
journal article 2010
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Rots, J.G. (author), Invernizzi, S. (author), Belleti, B. (author), Hendriks, M.A.N. (author)
conference paper 2009
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Nguyen, V.P. (author), Stroeven, M. (author), Sluys, L.J. (author)
In this contribution, we present the mechanical behaviour of the hardening cement paste explicitly taking into account its complex microstructure. The microstructure of the cement paste is obtained via numerical cement hydration simulation. A simple nonlocal isotropic damage model is adopted for different constituents of the cement paste. The...
conference paper 2009
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This booklet comprises the extended abstracts to be presented at the Ma(gni)FiCo workshop held in Delft, The Netherlands, on 17-18 June 2009. The spirit of this workshop is to have a small gathering with ample time for lively conversation and interaction among the student and faculty researchers. As a partial acronym, Ma(gni)FiCo stands for a...
book 2009
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Van Kasteren, J. (author)
Even concrete is not as hard as it looks. Sea water, salt on icy roads, and indirectly even carbon dioxide from the air can corrode the steel of the reinforcing bars and so threaten the strength and integrity of a bridge pier, jetty, or viaduct. Dessi Koleva, a chemical engineer from Bulgaria, spent her doctoral research at the Faculty of Civil...
journal article 2006
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Stroeven, P. (author), Guo, Z. (author)
This paper concentrates on discrete element computer-simulation of concrete. It is argued on the basis of stochastic heterogeneity theory that modern concurrent-algorithm-based systems should be employed for the assessment of pore characteristics underlying durability performance of cementitious materials. The SPACE system was developed at Delft...
journal article 2006
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