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Zhao, Shengying (author), Guan, Xinchun (author), Qiao, Guofu (author)Superabsorbent polymer (SAP) can modify the microstructure and influence the mechanical properties of cement paste in at least two ways: while cavities left by SAP increase the total porosity, water released by SAP affects the hydration degree of the surrounding paste. As a starting point for investigation into the overall effect, this study...conference paper 2021
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Zhang, H. (author), Schlangen, E. (author), Ge, Z. (author), Šavija, B. (author)Properties of concrete are, to a large extent, dependent on the properties of its binding constituent, hydrated cement paste. Therefore, knowledge of properties of hydrated cement paste is crucial for predicting concrete behaviour. This paper presents an experimentally informed approach for modelling elastic and transport properties of cement...conference paper 2021
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Ji, Yanliang (author), Sun, Zhenping (author), Pel, Leo (author), Pang, Min (author)Bleeding can be described as water coming out from fresh cement paste, which not only affects the homogeneity at fresh stage but also decides the hardened state structure. Previous studies have focused on the determination or simulation of the bleeding extent of fresh cement paste and give objective conclusions. However, there are rare...conference paper 2021
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Tsitova, Aliaksandra (author), Bernachy-Barbe, Fabien (author), Bary, Benoît (author), Hild, François (author)The safety of double wall Concrete Containment Buildings (CCBs) in the French nuclear fleet primarily depends on the level of prestress applied to concrete. The delayed strains in concrete induced by creep and shrinkage cause a loss of prestress in the inner wall that may increase the risk of potential leaks in accidental conditions. The creep...conference paper 2021
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Bai, Shuai (author), Guan, Xinchun (author), Li, Hui (author), Ou, Jinping (author)The purpose of this study is to explore the potential of nano-SiO2 (NS) to prevent early frost damage, and the effect of nano-SiO2 (NS) on cement pastes subjected to early-age freezing was investigated regarding the macro properties (strength and durability) and micro properties (hydration and microstructure). The specimens were prepared with NS...conference paper 2021
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Gu, Chunping (author), Ji, Yongjie (author), Yang, Yang (author), Liu, Jintao (author), Ni, Tongyuan (author)Sewage sludge ash (SSA) is the combustion residue of the sewage sludge obtained from wastewater treatment plants. In China, SSA normally contains high content of SO3, which may cause detrimental effect on the volume stability of cement-based materials. This study investigated the effect of sulfate-rich SSA (SR-SSA) on the volume deformation and...conference paper 2021
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Krishnya, S. (author), Yoda, Y. (author), Elakneswaran, Y. (author)Mechanical properties of cement paste are indispensable and frequent requirement in structural analysis of concrete and other cement-based materials, and therefore the theoretical predictions have obtained considerable attention in the field of material engineering. Despite of being an active research area, available models for accurately...conference paper 2021
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Zhang, H. (author), Schlangen, E. (author), Ge, Zhi (author), Šavija, B. (author)Properties of concrete are, to a large extent, dependent on the properties of its binding constituent, hydrated cement paste. Therefore, knowledge of properties of hydrated cement paste is crucial for predicting concrete behaviour. This paper presents an experimentally informed approach for modelling elastic and transport properties of cement...conference paper 2021
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Mercuri, L. (author), Romero Rodriguez, C. (author), Xu, Y. (author), Chaves Figueiredo, S. (author), Mors, R.M. (author), Rossi, E. (author), Anglani, G. (author), Antonaci, P. (author), Šavija, B. (author), Schlangen, E. (author)Soft inclusions, such as capsules and other particulate admixtures are increasingly being used in cementitious materials for functional purposes (i.e. self-healing and self-sensing of concrete). Yet, their influence on the fracture behaviour of the material is sometimes overlooked and requires in-depth study for the optimization of mechanical...conference paper 2019
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Gan, Y. (author), Zhang, H. (author), Šavija, B. (author), Schlangen, E. (author), van Breugel, K. (author)Nanoindentation is usually used to investigate local elastic properties and hardness of materials. In this paper, the nanoindenter served as a loading tool to perform micro scale bending tests and measure the global response of micro-scale specimens. For testing, cement paste cantilever beams with a square cross-section of 300 μm × 300 μm were...conference paper 2019
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Gastaldi, D. (author), Canonico, F. (author)Current concrete recycling consists of crushing waste concrete and use it again as aggregate for new concrete, according to specifications which are based on local regulations in different countries. Construction and demolition waste recycling is generally limited to the use of the coarser fraction as aggregate for new concrete. The quality of...conference paper 2017
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Li, K. (author), Stroeven, P. (author), Stroeven, M. (author), Sluys, L.J. (author)Permeability of virtual cement seems to exceed experimental data by several orders of magnitude. The differences may actually not be that dramatic, since experimental samples are in practice not always fully saturated as generally assumed. This paper demonstrates that this has enormous effects on permeability. A numerical study is conducted on...conference paper 2015
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Huang, H. (author), Ye, G. (author), Damidot, D. (author)In this paper, the proposed coupled transport-reaction model adapted to simulate autogenous self-healing in Portland cement paste is validated with the experimental results. The parameters are studied for modelling the dissolution of cement, the diffusion of ions between the solution in the crack and in the bulk paste and the precipitation of...conference paper 2014
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Lu, T. (author), Koenders, E.A.B. (author)In this paper, a conceptual model for analyzing the plastic part of autogenous deformation of cement paste based on the Arrhenius rate theory will be presented. The autogenous deformation will be calculated from the elastic deformations with inclusion of creep. Different kinds of cement paste with a water cement ratio 0.3 are tested and studied,...conference paper 2014
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Hoornahad, H. (author), Koenders, E.A.B. (author)In this paper, the effect of the mix composition on rheological behavior of a mixture is studied by considering a two-phase model for a mixture. A mixture is decomposed into a granular and a paste phase. Paste itself is divided into the void paste and the excess paste. The slump test is used for evaluation of rheological behavior of a mixture....conference paper 2013
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Jankovic, D. (author)Scattered and discontinues microcracking as a subsequent side-effect of deformations due to early age drying, occurs in thin (approximately 1 mm thick) cement paste samples, when stepwise dried in ESEM. Microcracking of cement paste and restrains appear to be practically unavoidable. They are related to a phenomenon of interfaces (‘matrix’ and ...conference paper 2009
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Jankovic, D. (author)Novel modifications of an environmental scanning electron microscope (ESEM) were made in order to measure the local deformations in drying cement paste. These nondestructively determined moisture-induced plane strains, obtained in 1 mm thick cement paste samples, are orthotropic. They vary with variations of relative humidity between 70%-80% and...conference paper 2008
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Jankovic, D. (author)Defining the 'real' shrinkage values of concrete is still a subject of much debate. In shrinkage experiments size effects are inherently present. Through an attempt to determine the real shrinkage of cement-based materials, these size effects have to be eliminated or at least reduced as much a possible. In this contribution drying shrinkage...conference paper 2007
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Jankovic, D. (author), Van Mier, J.G.M. (author)In order to perform drying shrinkage observations in ESEM (Environmental Scanning Electron Microscope), a preparation procedure for cement paste samples is developed. Instead of casting standard prisms (40 x 40 x 160 mm3), cement paste samples were cast in specially designed moulds of 30 x 30 x 2 mm3 and 10 x 10 x 2 mm3 in size. A special...conference paper 2002