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Van Der Putten, J. (author), Snoeck, D. (author), De Schutter, G (author), Van Tittelboom, K. (author)
Nowadays, 3D printing of cementitious materials is a hot research topic in the construction industry. This construction method is capable of producing complex geometries and largescale components without the use of expensive formwork. However, due to the lack of molding, more shrinkage will be induced and the amount of cracks will increase. As...
conference paper 2021
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Rossi, Emanuele (author), Zhang, Hongzhi (author), Çopuroğlu, Oğuzhan (author), Polder, Rob B. (author), Šavija, Branko (author), Nijland, Timo G. (author)
An important input parameter for numerical models that simulate cracking of the concrete cover due to reinforcement corrosion is the Elastic modulus of corrosion product (Ecp). Despite its relevance, Ecp is subject of significant variations according to the values reported in the literature, which vary from less than 100 MPa up to 360 GPa....
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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Wang, Tiao (author), Luan, Yao (author)
Reinforcement corrosion induced by chloride ingress is one of the major threats of reinforced concrete (RC) structures exposed to chloride attack. The cracks of concrete cover provide additional paths of chloride ingress and facilitate the reinforcement corrosion. Current information regarding the influence of crack development on corrosion...
conference paper 2021
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Gonthier, Julien Nicolas (author), Wilson, William (author), Georget, Fabien (author), Scrivener, Karen (author)
The incorporation of supplementary cementitious materials (SCMs) in cement pastes enables both decreasing CO2 emissions and increasing the concrete durability, notably with a better resistance against chloride ingress and thus retarding the chlorideinduced corrosion of steel rebars. Nevertheless, a better understanding of the chloride fixation...
conference paper 2021
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Romero Rodriguez, Claudia (author), Ye, Rui (author), Varveri, Aikaterini (author), Rossi, Emanuele (author), Anglani, Giovanni (author), Antonaci, Paola (author), Schlangen, Erik (author), Šavija, Branko (author)
Coupling of carbonation and chlorides ingress mechanisms is very common in concrete under certain exposure conditions such as coastal environments. The aggravation/ mitigation of corrosion by the existence of carbonation lies on the fact that microstructural changes due to carbonation result in changes on the transport properties of the material...
conference paper 2021
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Oesch, Tyler (author), Weise, Frank (author), Marx, Heidi (author), Kositz, Mario (author), Huenger, Klaus-Juergen (author)
Intensified Alkali-Silica Reaction (ASR) damage has occurred on German roadways in recent years, leading to requirements for compulsory pre-construction investigation of aggregate alkali sensitivity using concrete tests with external alkali supply. However, since these tests are time-consuming and cost-intensive, there is interest in replacing...
conference paper 2021
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de Azambuja, Carolina M. (author), Silva, Eugênia F. (author), Capuzzo, Valdirene M.S. (author)
The High Strength Concretes (HSC) provided significant advances in civil construction, due its superior strength, efficiency and durability. Due to the high content of cement, low water/cement ratio and mineral additions, it is essential to avoid the emergence of tensile stresses generated autogenous shrinkage and consequently the cracking of...
conference paper 2021
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De Maeijer, Patricia Kara (author), Craeye, Bart (author), Kazemi-Kamyab, Hadi (author), Snellings, Ruben (author), Loots, Michel (author)
In the present study, a proprietary 0.2 tonne/h Dusty Cloud Separation (DCS) technology prototype by Value Ash Technologies NV (Belgium) was used to obtain ultra-fine fly ash as a novel by-product. Two types of Class F fly ash were used: separated fly ash (FA1) with particle size < 9.3 μm and ultra-fine fly ash (FA2) < 4.6 μm as sub-fraction of...
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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Takahashi, Yuya (author), Gong, Fuyuan (author), Maekawa, Koichi (author)
Using numerical simulations, this study investigated the concrete expansion damage caused by the coupled action of freeze-thaw cycles (FTC) and alkali silica reactions (ASR). In the authors’ previous experiments, it was shown that a preceding ASR definitely accelerated the succeeding expansion by FTC. Further, even if the specimens have...
conference paper 2021
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Boutz, M.M.R. (author), Van Der Wegen, G.J.L. (author), Sarabèr, A.J. (author)
The time dependency of the chloride diffusion coefficient, the so-called ageing coefficient, of fly ash concrete has been investigated. The effect of origin of the fly ash as well as the origin and strength level of the cement combined with the fly ash, has been determined. Results obtained using the RCM-method on samples aged up to 5 years...
conference paper 2021
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Krstic, Marija (author), Davalos, Julio F. (author), Rossi, Emanuele (author), Figueiredo, Stefan C. (author), Copuroglu, Oguzhan (author)
Over the last few years, the United States has experienced a shortage of fly ash and slag that consequently created a need for an alternative material that is locally available, sustainable, and provides desirable concrete properties. Recent studies have shown that Ground Glass Pozzolan (GGP) offers favorable attributes as a supplementary...
conference paper 2021
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Handa, Kohsuke (author), Ye, Guang (author)
In this study, we targeted a calcium hydroxide and ettringite composite-type expansive additive (EA) and obtained the basic characteristics of the EA mixed cement paste in order to create a method for calculating volume expansion based on the hydration reaction of the PCEA system. Expansion strain, setting time, and compressive strength were...
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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GevaudanE, Juan Pablo (author), Bernal, Susan A. (author)
The aim of this study is to understand the corrosion mechanism of steel embedded in alkali-activated slag/metakaolin blended concretes via electrochemical testing after 407 days of exposure to a 3.5 wt.% NaCl solution, with an emphasis on characterising the material prior to the onset of corrosion. In order to accurately depict the material’s...
conference paper 2021
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Pang, Min (author), Sun, Zhenping (author), Ji, Yanliang (author), Yang, Jingbin (author), Wang, Peiming (author), Xu, Yaling (author), Li, Huanhuan (author), Liu, Jiaying (author), Li, Fei (author)
Characteristics of fly ash(FA) blended mortars (50%, 70% and 90%) at different curing ages (28 days and 180 days) under ammonium chloride solution(ACS) leaching were investigated. Mass loss under leaching, initial CaO content, Ca(OH)2 content(CH), content of chemical bonded water, and hydration degree of blended pastes were tested by XRF and DSC...
conference paper 2021
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Zhang, Jingxiao (author), Ma, Yuwei (author), Zheng, Jiazheng (author)
The widespread application of alkali-activated fly ash/slag (AAFS) concrete requires satisfaction of a series of performance criteria both from its early age properties (e.g. workability, strength) and long-term stability. In this study, long-term (till 180 days) natural chloride diffusion tests were conducted to evaluate the chloride diffusion...
conference paper 2021
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Nedeljković, Marija (author), Arbi, Kamel (author), Ye, Guang (author)
The reduction of pH from ~12.5 to ~9 by carbonation of the pore solution of reinforced cementbased concrete structures results in the reinforcement corrosion. The rate of carbonation is an important input for design of the concrete cover depth and the service life prediction of reinforced concrete structures because the initiation of...
conference paper 2021
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Sui, Shiyu (author), Georget, Fabien (author), Jiang, Jinyang (author), Scrivener, Karen (author)
Chloride binding is an important factor for chloride transport in cementitious materials, which can fix the chloride on the solid phase and decrease the free chloride content. As an alumina-rich supplementary cementitious material, calcined clay can be applied to improve the binding capacity of the system. While the contribution of calcined clay...
conference paper 2021
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