Blar i NTNU Open på forfatter "Justnes, Harald"
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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 ... -
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 ... -
Calcareous smectite clay as a pozzolanic alternative to kaolin
Danner, Tobias; Norden, Geir; Justnes, Harald (Journal article; Peer reviewed, 2019)The hydration of cement pastes with addition of a kaolinite rich clay (Clay A) and a calcareous smectite rich clay (Clay B) was investigated with isothermal calorimetry, in-situ XRD, PXRD, TGA and EPMA. Portland cement was ... -
Cements for tunnel grouting – Rheology and flow properties tested at different temperatures
Bohloli, Bahman; Skjølsvold, Ola; Justnes, Harald; Olsson, Roger; Grøv, Eivind; Aarset, Arnstein (Journal article; Peer reviewed, 2019)This paper presents work being carried out in Work Package 3 of TIGHT (True Improvement in Grouting High pressure Technology for tunnelling) project. The objective is to investigate flow and mechanical properties of three ... -
Characterisation of calcined raw clays suitable as supplementary cementitious materials
Danner, Tobias; Norden, Geir; Justnes, Harald (Journal article; Peer reviewed, 2018)The potential use of two raw clays (Clay A: kaolin; Clay B: calcareous montmorillonite) as supplementary cementitious material (SCM) in blended cements was investigated. Cement replacement in mortars by 20% calcined Clay ... -
Characterization of cement types used for rock injection
Skjølsvold, Ola; Justnes, Harald (Lecture, 2016)This paper is a part of the research project “True Improvement in Grouting High pressure Technology for tunneling (TIGHT)" financed by the Research Council of Norway (project no. 236676/O30), in cooperation with Statens ... -
Fibre reinforced lightweight aggregates
Bernhardt, Markus; Tellesbø, Hilde; Justnes, Harald; Wiik, Kjell (Journal article; Peer reviewed, 2014)Carbon steel fibre reinforced lightweight aggregates (LWA) were produced in a pilot scale rotary kiln. Narrow size fractions as well as not-sieved (asreceived) material were investigated according to European standards ... -
Mechanical properties of lightweight aggregates
Bernhardt, Markus; Tellesbø, Hilde; Justnes, Harald; Wiik, Kjell (Journal article; Peer reviewed, 2013)Lightweight aggregates (LWAs) were successfully produced both in a pilot-scale rotary kiln and in a laboratory chamber furnace. The mechanical properties of LWA were investigated in detail applying the European standard ... -
On the effect of calcium lignosulfonate on the rheology and setting time of cement paste
Colombo, Alessia; Geiker, Mette Rica; Justnes, Harald; Lauten, Rolf Andreas; De Weerdt, Klaartje (Journal article; Peer reviewed, 2017)The effect of softwood calcium lignosulfonate, LSs, on the rheology and setting time of cement paste has been investigated. Two Portland cements with different surface area and C3A content were used. The lignosulfonate was ... -
On the mechanisms of consumption of calcium lignosulfonate by cement paste
Colombo, Alessia; Geiker, Mette Rica; Justnes, Harald; Lauten, Rolf Andreas; De Weerdt, Klaartje (Journal article; Peer reviewed, 2017)The aim of this paper is to assess the mechanisms of consumption of softwood calcium lignosulfonate (LSs) by cement paste. The LSs consumption by two different cements (CX and ANL) and two reference materials (CaCO3 and ... -
The effect of additives on the properties of lightweight aggregates produced from clay
Bernhardt, Markus; Justnes, Harald; Tellesbø, Hilde; Wiik, Kjell (Journal article; Peer reviewed, 2014)In an attempt to improve the properties, lightweight aggregates were produced from clay with the addition of Na2CO3, SiO2, Fe2O3, and Fe in quantities between 2 and 10 wt% and examined with respect to strength, density and ... -
The effect of calcium lignosulfonate on ettringite formation in cement paste
Colombo, Alessia; Geiker, Mette Rica; Justnes, Harald; Lauten, Rolf A; De Weerdt, Klaartje (Journal article; Peer reviewed, 2018)The effect of a softwood calcium lignosulfonate, LSs, on the ettringite formed in cement paste was investigated. Two Portland cements, mainly differing in surface area and C3A content, were used. The effect of LSs addition ... -
The effect of heat treatment and cooling rate on the properties of lightweight aggregates
Bernhardt, Markus; Tellesbø, Hilde; Justnes, Harald; Wiik, Kjell (Journal article; Peer reviewed, 2014)Lightweight aggregates (LWA) were produced from clay in the laboratory. After firing different heat treatments and cooling rates were applied andthe resulting material was investigated with respect to strength and ... -
The interaction between calcium lignosulfonate and cement
Colombo, Alessia (Doctoral theses at NTNU;2017:20, Doctoral thesis, 2017)Modern concrete applications intensify the need for highly-flowable concretes, which are at the same time durable and possess good mechanical properties. The addition of plasticizers to the concrete mix allows obtaining ...