Browsing NTNU Open by Author "Machner, Alisa"
Now showing items 1-15 of 15
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Carbonation resistance of concrete and mortar containing novel low clinker cement
Bjørndal, Marie Helene (Student paper, others, 2019)Corrosion of reinforcement steel is a major deterioration mechanism for reinforced concrete structures. Corrosion can be caused by the carbonation of concrete. In this report we test the carbonation resistance of a novel ... -
Chloride binding in Portland composite cements containing metakaolin and silica fume
Babaahmadi, Arezou; Machner, Alisa; Kunther, Wolfgang; Figueira, João; Hemstad, Petter; De Weerdt, Klaartje (Peer reviewed; Journal article, 2022)This paper investigates how the composition of Portland composite cements affects their chloride-binding properties. Hydrated cement pastes prepared with a reference Portland cement and composite Portland cements containing ... -
Chloride-binding capacity of hydrotalcite in cement pastes containing dolomite and metakaolin
Machner, Alisa; Zajac, Maciej; Ben Haha, Mohsen; Kjellsen, Knut Ose; Geiker, Mette Rica; De Weerdt, Klaartje (Journal article; Peer reviewed, 2018)In this study, we investigated well-hydrated cement pastes containing dolomite and metakaolin cured at 38 °C or 60 °C, which were exposed to NaCl or CaCl2 solutions of various concentrations. We determined the chloride-binding ... -
Critical investigation of TGA sample preparation for composite cements
Machner, Alisa; Bussetti, Lucie; Geiker, Mette Rica; De Weerdt, Klaartje (Chapter, 2015)Thermogravimetric analysis (TGA) is a frequently used technique to investigate the phase assemblages of hydrated cements. However the obtained results are sensitive to the sample preparation. A commonly used technique for ... -
Effect of leaching on the composition of hydration phases during chloride exposure of mortar
Machner, Alisa; Bjørndal, Marie Helene; Justnes, Harald; Hanžič, Lucija; Šajna, Aljoša; Gu, Yushan; Benoît, Bary; Ben Haha, Mohsen; Geiker, Mette Rica; De Weerdt, Klaartje (Peer reviewed; Journal article, 2022)Mortar specimens were exposed to either a 3% NaCl solution or a 3% NaCl+KOH solution for up to 180 days. Exposure to the NaCl solution provoked much more leaching than the NaCl+KOH exposure. Leaching strongly impacted the ... -
Experimental carbonation study for a durability assessment of novel cementitious materials
Hanžič, Lucija; Robič, Sebastijan; Machner, Alisa; Bjørndal, Marie Helene; De Weerdt, Klaartje; Gu, Yushan; Bary, Benoît; Carreras, Rosa Maria Lample; Šajna, Aljoša (Peer reviewed; Journal article, 2021)Durability predictions of concrete structures are derived from experience-based requirements and descriptive exposure classes. To support durability predictions, a numerical model related to the carbonation resistance of ... -
Impact of leaching on chloride ingress profiles in concrete
Bjørndal, Marie Helene (Master thesis, 2019)Kloridinitiert armeringskorrosjon er en av hovednedbrytningsmekanismene for armerte betongkonstruksjoner. Klorider trenger igjennom betongoverdekningen over tid og forårsaker korrosjon når de når et kritisk kloridinnhold ... -
Investigation of the products of the dolomite reaction in Portland cement pastes
Machner, Alisa; Zajac, Maciej; Ben Haha, Mohsen; Kjellsen, Knut Ose; Geiker, Mette Rica; De Weerdt, Klaartje (Chapter; Peer reviewed, 2017)The formation of potentially deleterious reaction products from the reaction of dolomite fines in Portland cement pastes was investigated. It was shown that the reaction of dolomite fines did not follow the commonly accepted ... -
Limitations of the hydrotalcite formation in Portland composite cement pastes containing dolomite and metakaolin
Machner, Alisa; Zajac, Maciej; Ben Haha, Mohsen; Kjellsen, Knut Ose; Geiker, Mette Rica; De Weerdt, Klaartje (Journal article; Peer reviewed, 2018)This study focuses on the reaction of dolomite powder in combination with metakaolin in Portland composite cement pastes. We studied paste samples cured at 20 °C, 38 °C, and 60 °C for up to 1 year. In these systems, the ... -
Multi-scale strategy to estimate the mechanical and diffusive properties of cementitious materials prepared with CEM II/C-M
Gu, Yushan; Bary, Benoît; Machner, Alisa; De Weerdt, Klaartje; Bolte, Gerd; Ben Haha, Mohsen (Peer reviewed; Journal article, 2022)A procedure to estimate the mechanical and diffusive properties of cement pastes, mortars and concretes made with a novel CEM II/C-M (S-LL) binder that has been developed within the European EnDurCrete project, is presented ... -
pH-dependence of chloride binding in ordinary Portland cement
Hemstad, Petter (Master thesis, 2018)A new method for artificially leaching hydrated cement paste and studying how lowered pH in the pore solution affects chloride binding has been developed. Hydrated cement paste was exposed to a NaCl-solution before being ... -
Portland metakaolin cement containing dolomite or limestone – Similarities and differences in phase assemblage and compressive strength
Machner, Alisa; Zajac, Maciej; Ben Haha, Mohsen; Kjellsen, Knut O.; Geiker, Mette Rica; De Weerdt, Klaartje (Journal article; Peer reviewed, 2017)The scarceness of high-quality limestone obliges the cement industry to consider alternative supplementary cementitious materials (SCMs) for the production of blended cements. This study investigated the potential usage ... -
Stability of the hydrate phase assemblage in Portland composite cements containing dolomite and metakaolin after leaching, carbonation, and chloride exposure
Machner, Alisa; Zajac, Maciej; Ben Haha, Mohsen; Kjellsen, Knut Ose; Geiker, Mette Rica; De Weerdt, Klaartje (Journal article; Peer reviewed, 2018)To reduce CO2 emissions during the production of cement and to cope with increasing demands for concrete, and thereby cement, the cement industry needs to identify new supplementary cementitious materials. These new composite ... -
The effect of artificial leaching with HCl on chloride binding in ordinary Portland cement paste
Hemstad, Petter; Machner, Alisa; De Weerdt, Klaartje (Journal article; Peer reviewed, 2020)This study investigates how the pH in the pore solution influences the chloride binding in Portland cement pastes. Cement paste samples were exposed to NaCl, CaCl2 and HCl solutions. The mechanisms of changes in chloride ... -
Towards the Understanding of the pH Dependency of the Chloride Binding of Portland Cement Pastes
Machner, Alisa; Hemstad, Petter; De Weerdt, Klaartje (Journal article; Peer reviewed, 2018)Hydrated Portland cement paste exposed to a NaCl solution was acidified by adding HCl in small steps, gradually lowering the pH. The chloride binding of the cement paste changed as a function of the pH. For the range of ...