Blar i NTNU Open på forfatter "Lindgård, Jan"
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Alkali Aggregate Reactions (AAR) in concrete. The Norwegian endeavour during more than 3 decades of research
Wigum, Børge Johannes; Lindgård, Jan; De Weerdt, Klaartje; Pedersen, Bård Magne; Rønning, Terje F. (Chapter, 2022)It is now more than 80 years since Alkali Aggregate Reactions (AAR) first were reported as a deleterious deterioration mechanism in concrete. In Norway, AAR was recognised in the late nineteeneighties. Norwegian experience ... -
Alkali metal distribution in composite cement pastes and its relation to accelerated ASR tests
Hemstad, Petter; Zuschlag, Pamela; Kjellemyr, Petter; Lindgård, Jan; Kjellsen, Knut O.; Rønning, Terje; Justnes, Harald; Maciej, Zajac; Haha, Mohsen Ben; Weerdt, Klaartje de (Peer reviewed; Journal article, 2023)Accelerated testing of alkali silica reaction (ASR) in concrete at elevated temperatures of 38 and 60 °C has an unknown impact on the alkali metal distribution in the cement paste. This paper investigates how the alkali ... -
Alkali-silica reaction (ASR)-performance testing: Influence of specimen pre-treatment, exposure conditions and prism size on alkali leaching and prism expansion
Lindgård, Jan; Thomas, Michael D.A.; Sellevold, Erik Johan; Pedersen, Bård; Andiç-Çakır, Özge; Justnes, Harald; Rønning, Terje F. (Journal article; Peer reviewed, 2013)Whether or not concrete prism tests developed for assessment of alkali–silica reactivity of aggregates might be suitable for general ASR performance testing of concrete has been evaluated. This paper discusses how variations ... -
Alkalireaksjon i betongdammar ved Tyinosen - Metode, resultat og tiltak
Rockland Aarethun, Kristen Johannes (Master thesis, 2019)Masteroppgåva tek føre seg ulike metodar for vurdering av alkalireaksjon i Tyin Dam 1, 2 og 3, med omsyn til levetid og tiltak. På nedstraumsside er dammane prega av rutemønstra oppsprekking, kalkutfellingar og lekkasjar. ... -
Alkali‐silica reaction (ASR) – Performancetesting
Lindgård, Jan (Doktoravhandlinger ved NTNU, 1503-8181; 2013:269, Doctoral thesis, 2013)Whether or not concrete prism tests developed for assessment of alkali‐silica reactivity of aggregates is suitable for general ASR performance testing of concrete has been evaluated. The work has been part of the Norwegian ... -
Alkali–silica reaction (ASR)—performance testing: Influence of specimen pre-treatment, exposure conditions and prism size on concrete porosity, moisture state and transport properties
Lindgård, Jan; Sellevold, Erik Johan; Thomas, Michael D.A.; Pedersen, Bård; Justnes, Harald; Rønning, Terje F. (Journal article; Peer reviewed, 2013)Whether or not concrete prism tests (CPTs) developed for assessment of alkali–silica reactivity of aggregates might be suitable for general ASR performance testing of concrete has been evaluated. This paper presents the ... -
Changes in cement paste during accelerated mortar bar testing for pyrrhotite containing aggregate
Weerdt, Klaartje de; Bagheri, Mahsa; Lindgård, Jan; Lindstad, Hallvard; Rodrigues, A.; Duchesne, J.; Fecteau, P.-L.; Haugen, Marit Kristin; Danner, Tobias; Wigum, Børge Johannes; Oberhardt, Nikolas; Aasly, Kari Aslaksen; Lothenbach, Barbara (Journal article; Peer reviewed, 2024)The accelerated mortar bar test (AMBT) for pyrrhotite (Fe1-xS) containing aggregates accelerates expansion using two regimes: Phase I, during which Fe1-xS oxidation to iron hydroxide is accelerated by bleach and storage ... -
Determination of the pH and the free alkali metal content in the pore solution of concrete: Review and experimental comparison
Plusquellec, Gilles; Geiker, Mette Rica; Lindgård, Jan; Duchesne, Josée; Fournier, Benoit; De Weerdt, Klaartje (Journal article; Peer reviewed, 2017)The durability of concrete is affected by the pH of its pore solution, which is linked to the free alkali metal content. This paper starts with a literature review of methods for determining the pH and/or the free alkali ... -
Determining alkali content in ASR performance-tested concrete
Kermit, Peter Holiman (Master thesis, 2017)Alkali silica reation (ASR) is a common deterioration mechanism of concrete. During ASR, reactive aggregate containing silicon oxide (SiO2) can react with the alkaline fluid in the concrete pores. To test whether a concrete ... -
Determining alkali leaching during accelerated ASR performance testing and in field exposed cubes using cold water extraction (CWE) and μXRF
Lindgård, Jan; Østnor, Tone Anita; Fournier, Benoit; Lindgård, Øyvind; Danner, Tobias; Plusquellec, Gilles; De Weerdt, Klaartje (Journal article; Peer reviewed, 2018)Considerable leaching of alkali metals was documented, both in concrete samples exposed to accelerated laboratory testing and field samples. CWE allowed to quantitatively determine the free alkali metal profiles as a ... -
Determining the free alkali metal content in concrete – Case study of an ASR-affected dam
Plusquellec, Gilles; Geiker, Mette Rica; Lindgård, Jan; De Weerdt, Klaartje (Journal article; Peer reviewed, 2018)In concrete affected by alkali–silica reaction (ASR), aggregates react in the high pH environment and cause deleterious expansion and cracking of the concrete. Leaching of alkali metals from the concrete might therefore ... -
Frost dilation measurements on concrete cores from a dam with ASR
Jacobsen, Stefan; Lindgård, Jan; Fritz, Leonie (Chapter, 2008)In order to evaluate length change measurements to determine damage in concrete due to both ASR and internal frost attack, concrete cores drilled from a 25 year old dam with slight ASR and some surface frost damage were ... -
Fundamental study on ASR kinetics - effect of temperature on aggregate reactivity and pore-water composition
De Weerdt, Klaartje; Hemstad, Petter; Justnes, Harald; Østnor, Tone Anita; Rønning, Terje F.; Lindgård, Jan (The International Conference on Alkali-Aggregate Reaction (ICAAR);Theme 4, Chapter, 2021) -
Investigations on the feasibility of the CWE method to verify potential alkali release from aggregates in Norwegian field concrete
Danner, Tobias; De Weerdt, Klaartje; Pedersen, Bård Magne; Lindgård, Jan (Chapter, 2021)Concrete elements exposed for 26 years to seawater spray and deicing salts along a road close to Sandnessjøen in Norway were investigated. Concrete cores from 4 elements with different binder compositions (A: 100 % Portland ... -
Laboratory and field investigations of alkali-silica reaction prevention by supplementary cementitious materials: Influence of the free alkali loading
Ranger, Maxime; Hasholt, Marianne Tange; Lindgård, Jan; Barbosa, Ricardo Antonio (Journal article; Peer reviewed, 2024)Performance tests are often used to evaluate the effect of supplementary cementitious materials (SCMs) on alkali-silica reaction (ASR). However, these tests may be quite demanding, thus other approaches may be more efficient ... -
NDT methods and sensors for existing concrete structures. Literature review
Popescu, Cosmin; Danner, Tobias; Myrdal, Roar; Lindgård, Jan; Revert, Andres Belda; Täljsten, Björn (SINTEF AS (ISBN starter med 978-82-14-), Research report, 2023) -
Outdoor exposure site testing for preventing Alkali-Aggregate Reactivity in concrete – a review
Fournier, Benoit; Lindgård, Jan; Wigum, Børge Johannes; Borchers, Ingmar (Journal article; Peer reviewed, 2018)Alkali-silica reaction (ASR) is a deleterious chemical reaction affecting the durability and service life of concrete structures worldwide. Specifications and recommendations were produced in many countries to ensure that ... -
Pyrrhotite in concrete aggregate. Introduction to mechanism, damage potential and ongoing research
Lindstad, Hallvard; Lindgård, Jan; Pedersen, Bård Magne; Wigum, Børge Johannes; Aasly, Kurt; Ullnæss, Inger Lise; Oberhardt, Nikolas; De Weerdt, Klaartje (Chapter, 2022)Pyrrhotite is an iron sulfide which when present in concrete aggregate may lead to expansive reactions, cracks and finally disintegration of the concrete. This potential risk when using aggregates containing sulfides in ... -
Relative humidity measurements in concrete
Hepsøe, Per Martin (Master thesis, 2017)A commonly used way to monitor the concrete s moisture condition is to measure Relative humidity (RH). Measuring relative RH in concrete, and understanding the underlying mechanisms are complex tasks. Field measurements ... -
Rilem activities on alkali-silica reactions: from 1988-2019
Wigum, Børge Johannes; Lindgård, Jan; Sims, Ian; Nixon, Philip J (Journal article; Peer reviewed, 2016)Since 1988, the International Union of Laboratories and Experts in Construction Materials, Systems and Structures (Rilem) technical committees (TCs) have been seeking to establish universally applicable test methods for ...