Searched for: faculty%3A%22Civil%255C%252BEngineering%255C%252Band%255C%252BGeosciences%22
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Susanto, A. (author), Koleva, D.A. (author), Van Breugel, K. (author)
This work reports on the influence of stray current flow on temperature rise in hardening cement-based materials and consequently altered cement hydration. To simulate stray current, different levels of electrical current were applied to cement paste and mortar specimens immediately after casting. Isothermal calorimetry tests were carried out to...
conference paper 2015
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Patel, R.A. (author), Perko, J. (author), Jacques, D. (author), De Schutter, G. (author), Van Breugel, K. (author), Ye, G. (author)
Calcium leaching is one of the important degradation mechanisms causing dissolution of the crystalline phases such as, AFm, portlandite increasing capillary porosity. Further it leads to decalcification of an amorphous C-S-H phase causing increase in the gel porosity and in turn degrading the long term performance of concrete structures. In this...
conference paper 2014
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Van Breugel, K. (author), Van Tuan, N. (author)
conference paper 2014
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Susanto, A. (author), Koleva, D.A. (author), Van Breugel, K. (author)
This paper reports on the influence of stray current flow on microstructural prop-erties, i.e. pore connectivity and permeability of mortar specimens, and link these to the observed alterations in mechanical properties and cement hydration. Mortar specimens were partly submerged in water and calcium hydroxide (Ca(OH)2) as an external environment...
conference paper 2014
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Susanto, A. (author), Koleva, D.A. (author), Van Breugel, K. (author)
This paper investigates DC current-induced “curing” and ageing phenomena in cement-based materials. Two current densities were used in a DC current regime i.e. mortar cubes were subjected to DC current flow of 1 A/m2 and 100 mA/m2; tap water and calcium hydroxide were external environment. Conditioning (“curing”) was performed for 112 days,...
conference paper 2014
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Pargar, F. (author), Koleva, D.A. (author), Koenders, E.A.B. (author), Van Breugel, K. (author)
One of the reported problems associated with the performance of Ag/AgCl electrodes in alkaline environment, as concrete pore water, has been their poor stability. Open circuit potentials are typically observed to be stable for a time period of a few minutes to some days depending on the thickness and microstructure of the sparingly soluble AgCl...
conference paper 2014
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Yu, Z. (author), Ye, G. (author), Van Breugel, K. (author), Chen, W. (author)
Deterioration of microstructure in cement concrete will cause changes in the transport properties of the concrete. Transport properties at different ages of the concrete provide information about the microstructural changes of the material. A way to measure the transport properties, i.e. the chloride diffusion coefficient, in the laboratory is...
conference paper 2014
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Susanto, A. (author), Koleva, D.A. (author), Van Breugel, K. (author), Koenders, E.A.B. (author)
Stray current is essentially an electrical current “leakage” from metal conductors and electrical installations. When it flows through cement-based systems, electrical energy is converted to thermal energy that causes increasing temperature due to Joule heating phenomena. The aim of this paper is to shed light on the influence of electrical...
conference paper 2014
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Van Breugel, K. (author), Van Tuan, N. (author)
Ultra High Strength Concrete (UHPC) is generally made with low w/c mixtures and by adding silica fume. Low w/c mixtures, however, exhibit high autogenous shrinkage, while a high amount of silica fume increases the price of these mixtures. For designing ultra high strength mixtures with low autogenous shrinkage and lower costs the possibility of...
conference paper 2014
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Van Breugel, K. (author)
The increasing demand for quality, durability and sustainability requires a critical evaluation of currently used building codes. Although there is no doubt that we need codes, standards, certificates etc., the existence of these documents are no guarantee that the prescribed quality is realized on the building site. In this paper the essential...
conference paper 2014
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Hu, J. (author), Koleva, D.A. (author), Ma, Y. (author), Schlangen, E. (author), Van Breugel, K. (author)
journal article 2013
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Susanto, A. (author), Koleva, D.A. (author), Van Beek, C. (author), Van Breugel, K. (author)
Well known is that stray electrical current i.e. current with a spatial distribution in any conductive environment, can affect civil structures, e.g. initiate or enhance steel corrosion or affect microstructural and mechanical properties of the cement-based bulk matrix. While the former is related to polarization effects in conditions of current...
conference paper 2013
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Patel, R.A. (author), Perko, J. (author), Jaques, D. (author), De Schutter, G. (author), Ye, G. (author), Van Breugel, K. (author)
A Lattice Boltzmann (LB) based reactive transport model intended to capture reactions and solid phase changes occurring at the pore scale is presented. The proposed approach uses LB method to compute multi component mass transport. The LB multi-component transport model is then coupled with the well-established geochemical reaction code PHREEQC...
conference paper 2013
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Leon Fuenmayor, E.J. (author), Koleva, D.A. (author), Jonkers, H.M. (author), Mol, J.M.C. (author), Terryn, H. (author), Van Breugel, K. (author)
Impressed current cathodic protection (CP) based on pulse technology has been proven to be a more efficient and effective alternative of traditional CP for reinforced concrete applications. Essentially, the superiority of pulse CP is in achieving the required steel polarization with otherwise reduced side effects (e.g. influence on bond strength...
conference paper 2013
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Varini, M. (author), Koleva, D.A. (author), Denkova, A.G. (author), Mol, J.M.C. (author), Terryn, H. (author), Van Breugel, K. (author)
Polymeric nano-materials utilization in reinforced concrete, aiming to deal with steel corrosion was developed in previous works. Promising results were obtained with PEO–b–PS nano-formations, both in terms of enhanced bulk matrix properties and improved steel corrosion resistance. Recent research has been focusing on a cheaper and commercially...
conference paper 2013
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Ukrainczyk, N. (author), Koenders, E.A.B. (author), Van Breugel, K. (author)
conference paper 2013
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Susanto, A. (author), Koleva, D.A. (author), Copuroglu, O. (author), Van Beek, C. (author), Van Breugel, K. (author)
This investigation presents a comparative study on mechanical properties, electrical resistivity and microstructure of mortar under DC current, compared to mortar in rest (no current) conditions. Monitoring was performed from 24h after casting until 84 days of cement hydration. A current density level of 10 mA/m2 was chosen as a simulation...
journal article 2013
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Agar Ozbek, A.S. (author), Weerheijm, J. (author), Schlangen, H.E.J.G. (author), Van Breugel, K. (author)
Porous concrete is used in many applications that require permeability, noise absorption or thermal insulation. However, its response under dynamic loading is generally not considered. Porous concrete has a characteristic of forming multiple cracks and subsequently fracturing into small fragments when exposed to impact loading. Therefore, with...
conference paper 2013
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Koleva, D.A. (author), Van Breugel, K. (author)
This work reports on the corrosion resistance of steel in alkaline model solutions and in cement-based materials (mortar). The model solutions and the mortar specimens were Ordinary Portland Cement (OPC) based. Further, hereby discussed is the implementation of an eco-friendly approach of waste utilization for corrosion control and/or achieving...
conference paper 2012
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Susanto, A. (author), Koleva, D.A. (author), Copuroglu, O. (author), Van Beek, C. (author), Van Breugel, K. (author)
Corrosion in reinforced concrete structures is not only induced by the penetration of aggressive substances (e.g. chlorides and/or CO2) but also influenced by stray currents. Further, the degradation mechanisms in reinforced cement-based systems due to the combined effect of stray current and chloride penetration have been a serious problem in...
conference paper 2012
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