TY - JOUR A1 - Roussel, N. A1 - Gram, A. A1 - Cremonesi, M. A1 - Ferrara, L. A1 - Krenzer, K. A1 - Mechtcherine, V. A1 - Shyshko, S. A1 - Skocec, J. A1 - Spangenberg, J. A1 - Svec, O. A1 - Thrane, L. N. A1 - Vasilic, Ksenija T1 - Numerical simulations of concrete flow: A benchmark comparison N2 - First, we define in this paper two benchmark flows readily usable by anyone calibrating a numerical tool for concrete flow prediction. Such benchmark flows shall allow anyone to check the validity of their computational tools no matter the numerical methods and parameters they choose. Second, we compare numerical predictions of the concrete sample final shape for these two benchmark flows obtained by various research teams around the world using various numerical techniques. Our results show that all numerical techniques compared here give very similar results suggesting that numerical simulations of concrete filling ability when neglecting any potential components segregation have reached a technology readiness level bringing them closer to industrial practice. KW - Casting KW - Fresh Concrete KW - Rheology KW - Workability KW - Modeling PY - 2016 UR - http://www.sciencedirect.com/science/article/pii/S0008884615002604 U6 - https://doi.org/10.1016/j.cemconres.2015.09.022 SN - 0008-8846 VL - 2016/79 SP - 265 EP - 271 PB - Elsevier Ltd. AN - OPUS4-37440 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vasilic, Ksenija T1 - A numerical model for simulations of concrete casting N2 - In the last decades, numerical simulations of fresh concrete flow have gained importance in concrete industry. They showed a potential to become a tool for prediction of concrete casting and to help engineers to avoid expensive mistakes on site. A promising field for application of numerical modelling is casting of Self-Compacting Concrete (SCC), since the main area of application of SCC are complex and highly-reinforced building elements. Simulations of fresh concrete flow involve complex mathematical models and time-consuming computations. In case of casting simulations, the simulation time is additionally significantly increased because each reinforcement bar occurring in succession has to be considered one by one. This is particularly problematic in case of SCC casting, since this type of concrete is typically used for heavily-reinforced structural members. With the aim to decrease simulation time and to come closer to a practical simulation tool, we proposed an innovative modelling approach that models a zone with arrays of the reinforcement bars as a porous medium (PM). By defining characteristic parameters of the PM, its influence on the flow can be defined. This approach simplifies the geometry to be modelled and significantly decreases the computational time. The present contribution provides a brief description the proposed numerical model and of the conducted validation studies. The applicability of the model on fresh concrete is verified through the comparison between experimental measurements and numerical simulations. T2 - WMRIF 5th International Workshop for Young Scientists CY - Tsukuba, Japan DA - 07.11.2016 KW - Fresh concrete KW - CFD simulation KW - Rheology KW - Casting KW - Reinforcement PY - 2016 AN - OPUS4-38514 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Vasilic, Ksenija A1 - Geiker, M. A1 - Hattel, J. A1 - Martinie, L. A1 - Martys, N. A1 - Roussel, N. A1 - Spangenberg, J. ED - Roussel, N. ED - Gram, A. T1 - Advanced methods and future perspectives N2 - The one-phase methods described in Chapter 2 were shown to be able to predict casting to some extent, but could not depict segregation, sedimentation and blockage occurring during flow. On the other hand, the distinct element methods described in Chapter 3 did not take into account the presence of two phases in the system and describes concrete as distinct elements interacting through more or less complex laws. A reliable numerical model of a multiphase material behaviour shall take into account both phases (solid and liquid). From the numerical point of view, concrete flow shall be seen therefore as the free surface flow of a highly-concentrated suspension of rigid grains. KW - SCC KW - Numerical simulation PY - 2014 SN - 978-94-017-8883-0 U6 - https://doi.org/10.1007/978-94-017-8884-7_5 VL - 15 SP - 125 EP - 146 PB - Springer Netherlands AN - OPUS4-37443 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vasilic, Ksenija A1 - Kühne, Hans-Carsten A1 - Meng, Birgit A1 - Roussel, N. ED - Rogge, A. ED - Meng, B. T1 - Modelling of fresh SCC flow through reinforced sections T2 - 52. DAfStb-Forschungskolloquium CY - Berlin, Deutschland DA - 2011-11-07 PY - 2011 SN - 978-3-9814281-0-0 SP - 50 EP - 57 PB - BAM Bundesanstalt für Materialforschung und -prüfung CY - Berlin AN - OPUS4-25193 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vasilic, Ksenija A1 - Kühne, Hans-Carsten A1 - Schmidt, Wolfram A1 - Roussel, N. T1 - Numerical simulations of scc casting: parameter determination N2 - The paper addresses numerical modelling of fresh self-compacting concrete. In the previous studies, a numerical tool for casting prediction is built based on the assumption that fresh concrete behaves as a yield-stress fluid and treating zones with rebars as porous media. The present contribution discusses the determination of material parameters, which are required as an input for numerical simulations of casting processes. T2 - International RILEM Conference on Materials, Systems and Structures in Civil Engineering 2016, Segment on Fresh Concrete CY - Lyngby, Denmark DA - 22.08.2016 KW - Fresh concrete KW - Simulation KW - CFD KW - Rheology PY - 2016 SN - 978-2-35158-184-1 SP - 163 EP - 172 PB - RILEM Publications S.A.R.L. CY - Paris, France AN - OPUS4-37446 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vasilic, Ksenija A1 - Meng, Birgit A1 - Kühne, Hans-Carsten A1 - Roussel, Nicolas T1 - Computational modelling of scc flow: reinforcement network modelled as a porous medium T2 - Rheo-Iceland 2009 3rd RILEM International Symposium on Rheology of Cement Suspensions Like Fresh Concrete CY - Reykjavik, Iceland DA - 2009-08-19 PY - 2009 AN - OPUS4-19403 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vasilic, Ksenija A1 - Meng, Birgit A1 - Kühne, Hans-Carsten A1 - Roussel, N. T1 - Flow of fresh concrete through steel bars: a porous medium analogy N2 - Although being a very promising area of concrete technology, computational modeling of fresh concrete flow is a comprehensive and time consuming task. The complexity and required computation time are additionally increased when simulating casting of heavily reinforced sections, where each single reinforcement bar has to be modeled. In order to improve the computation speed and to get closer to a practical tool for simulation of casting processes, an innovative approach to model reinforced sections is proposed here. The basic idea of this approach is to treat the reinforcement zone as a porous medium in which a concrete is propagating. In the present paper, the numerical implementation of this concept is described. A methodology allowing for the computation of the equivalent permeability of the steel bars network is suggested. Finally, this numerical technique efficiency is evaluated by a comparison with experimental results of model fluids casting in model formworks. KW - Fresh concrete (A) KW - Rheology (A) KW - Modeling (E) KW - Permeability (C) KW - Yield stress KW - Simulation KW - Flow of mortar KW - Flow of concrete PY - 2011 U6 - https://doi.org/10.1016/j.cemconres.2011.01.013 SN - 0008-8846 SN - 1873-3948 VL - 41 IS - 5 SP - 496 EP - 503 PB - Pergamon Press CY - New York, NY AN - OPUS4-25532 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Vasilic, Ksenija A1 - Roussel, N. A1 - Meng, Birgit A1 - Kühne, Hans-Carsten ED - Olafur H. Wallevik, ED - Stefan Kubens, ED - Sonja Oesterheld, T1 - Computational modelling of SCC flow: Reinforcement network modelled as porous medium T2 - 3rd International RILEM symposium on rheology of cement suspensions such as fresh concrete CY - Reykjavik, Iceland DA - 2009-08-19 KW - SCC KW - Modelling KW - CFD PY - 2009 SN - 978-2-35158-091-2 IS - PRO 68 SP - 148 EP - 154 PB - RILEM Publications AN - OPUS4-20238 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Vasilic, Ksenija A1 - Roussel, N. A1 - Meng, Birgit A1 - Kühne, Hans-Carsten ED - Khayat, K.H. ED - Feys, D. T1 - Computational modeling of SCC flow through reinforced sections N2 - Computational modeling of fresh SCC flow is a comprehensive and time consuming task. The computational time is additionally increased when simulating casting of reinforced sections, where each single reinforcement bar has to be modeled. In order to deal with this issue and to decrease the computational time, an innovative approach of treating a reinforcement network as a porous medium is applied. This contribution presents the model for concrete flow through reinforced sections, based on Computational Fluid Dynamics (CFD), coupling a single-phase flow model for SCC and a continuum macroscopic model for porous medium. In the last part of this paper, numerical simulations are compared with experimental results obtained on model fluids. T2 - SCC2010 - Design, production and placement of self-consolidating concrete CY - Montreal, Canada DA - 2010-09-26 PY - 2010 SN - 978-90-481-9663-0 U6 - https://doi.org/10.1007/978-90-481-9664-7_16 N1 - Serientitel: RILEM bookseries – Series title: RILEM bookseries VL - 1 IS - 5 SP - 187 EP - 195 PB - Springer AN - OPUS4-22277 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vasilic, Ksenija A1 - Schmidt, Wolfram A1 - Kühne, Hans-Carsten A1 - Haamkens, Frank A1 - Mechtcherine, V. A1 - Roussel, N. T1 - Flow of fresh concrete through reinforced elements: Experimental validation of the porous analogy numerical method N2 - Numerical simulations of concrete castings are complex and time consuming. In order to decrease simulation time and to simplify simulation procedure, an innovative modelling approach, which treats reinforced sections in a formwork as porous media, was proposed. In the previous studies, this numerical model was proved suitable to simulate casting of model yield-stress fluids through reinforced elements. This article focuses on the experimental validation of the proposed model at the concrete scale. For this purpose, a large-scale laboratory casting of a highly reinforced beam is performed. The casting process is numerically simulated and the numerical results are compared to the experimental measurements. KW - Porous medium KW - Self-compacting concrete KW - Casting KW - CFD simulation KW - Reinforcement PY - 2016 UR - http://www.sciencedirect.com/science/article/pii/S0008884616301880 U6 - https://doi.org/10.1016/j.cemconres.2016.06.003 SN - 0008-8846 VL - 2016/88 SP - 1 EP - 6 PB - Elsevier Ltd. AN - OPUS4-37441 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -