Effects of elevated temperatures on the thermal behavior and mechanical performance of fly ash geopolymer paste, mortar and lightweight concrete

Abdulkareem, Omar A.; Bakri, A.M. Mustafa Al; Kamarudin, H.; Nizar, Ismail Khairul; Saif, Ala’eddin A.

doi:10.1016/j.conbuildmat.2013.09.047

Cited by 297 publications

(93 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It was revealed in some studies [20,22,23] that while coarse aggregates progressively expanded at elevated temperatures, geopolymer binders experienced notable shrinkage. Furthermore, dehydration and dehydroxylation could be somewhat responsible for the reduction of strength [37]. However, on a larger scale, GB-6 had a similar capacity to GB-A.…”

Section: Load Capacity and Failurementioning

confidence: 99%

“…GB-4 obtained a remarkable improvement in yielding and ultimate capacity that was mainly attributable to the strengthening behaviour of GC. The enhancement of GC after temperature exposure was commonly reported in [18,33,36,37] that the alkali activation of the remnant precursors induced by ambient curing was catalysed by the high temperature when free water was not liberated. The augmentation of GC predominated over the damage brought about by vapor pressure and thermal incompatibility.…”

Section: Load Capacity and Failurementioning

confidence: 99%

See 1 more Smart Citation

Flexural Behaviour of Combined FA/GGBFS Geopolymer Concrete Beams after Exposure to Elevated Temperatures

Junru

Chen

Sun

et al. 2017

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

As a promising alternative to OPC concrete, geopolymer concrete has been investigated and has demonstrated superior mechanical performance. Studying the thermal behaviour on the scale of a structural element is significant for introducing a new material to engineering applications. Four geopolymer concrete beams and four OPC concrete counterparts with the same reinforcement structure and similar concrete strength were subjected to three different heating cases at the rate of ISO834. The experimental results showed that the geopolymer concrete beams underwent a colour change, severe cracking, and no spalling after the exposure. While under load, the geopolymer concrete specimens exhibited a lower crack resistance and flexural stiffness. The residual load capacities were 110%, 107%, and 90% of the ambient specimen for the geopolymer concrete samples and 103%, 97%, and 80% for the OPC concrete samples. To some extent, the geopolymer concrete beams achieved superior fire endurance compared to their OPC concrete counterparts.

show abstract

Section: Load Capacity and Failurementioning

confidence: 99%

Section: Load Capacity and Failurementioning

confidence: 99%

Flexural Behaviour of Combined FA/GGBFS Geopolymer Concrete Beams after Exposure to Elevated Temperatures

Junru

Chen

Sun

et al. 2017

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

show abstract

“…Geopolymer concrete at 800°C temperatures tends to have a lower compressive strength compared to the compressive strength at the other temperatures. The higher temperatures result in the decreasing of the compressive strength of geopolymer concrete [7], but at specific temperature, the strength of geopolymer increased. It was shown that the strength of the geopolymer concrete was influenced by dehydration and dehydroxylation [8,9].…”

Section: Compressive Strength Of the Specimensmentioning

confidence: 99%

“…The increase in temperatures led to the decrease of the compressive strength of geopolymer. The decreasing of the strength was caused by dehydration and dehydroxylation processes at the temperature 400°C to 600°C [7,8]. While heating from room temperature to 800°C, the OPC concrete greatly experienced cracking and spalling [5].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Mechanical Properties of Geopolymer Concrete Exposed to Combustion

Rahmadina

Ekaputri

2017

MATEC Web Conf.

View full text Add to dashboard Cite

Abstract. This paper presents the change of material properties, such as decreasing of the compressive strength, splitting tensile strength, and porosity. The main objective of this paper is to analyze the mechanical properties of fly ash-based geopolymer concrete after being exposed to high temperature. The 28 th -day test specimens were burned for one hour at specified temperature variation of 200°C, 400°C, 600°C, and 800°C. Ordinary Portland Cement (OPC) concrete was used as a comparison. After burning at 400°C, the compressive strength of geopolymer concrete was surprisingly increased up to 27% of its normal strength. On the other hand, the compressive strength of OPC concrete decreased 67% from its normal strength. The splitting tensile strength of geopolymer concrete also decreased at the range of 50-70%. The porosity of concrete has a sufficient effect to compressive strength and splitting strength. X-Ray Diffraction (XRD) test of geopolymer concrete at temperature 400°C until 600°C showed some minerals change. Geopolymer concrete is proved to have better fire resistance compares to Portland Cement Concrete.

show abstract

Einfluss der Kristallinität auf die Festigkeit und die Mikrostruktur alkalisch aktivierter Metakaoline

Lohmann,

Schmidt‐Döhl

2023

ce papers

View full text Add to dashboard Cite

KurzfassungBei der Reaktion von Metakaolin mit alkalischen Anregern entstehen eine röntgenamorphe, alumosilikatische Gelmatrix sowie kristalline Natrium‐ bzw. Calcium‐Aluminat‐Silikat‐Hydratphasen zu unterschiedlichen Anteilen. In dieser Arbeit wurden grundlegende Zusammenhänge zwischen dem Kristallinitätsgrad der alkalisch aktivierten Metakaoline sowie deren mechanischen Eigenschaften untersucht. Dabei wurde insbesondere auf die Porosität, die Druckfestigkeit und thermoanalytische Eigenschaften eingegangen. Die Kristallinität wurde mittels Röntgendiffraktometrie bestimmt. Voraussetzungen für die Ausbildung eines amorphen Gefüges ist die Lösung der reaktiven Ausgangsmaterialien. Nicht vollständige Lösung führt zu inhomogenem Gefüge, in dem sowohl amorphe Matrix als auch kristalline Bereiche vorliegen. Kristalline Reste im Metakaolin dienen als Kristallisationskeim und begünstigen die Bildung weniger stabiler kristalliner Hydratphasen. Es zeigte sich, dass ein höherer Kristallinitätsgrad mit größeren Poren und einem höheren Porenvolumen einherging, das die Druckfestigkeit der erhärteten Bindemittel herabsenkte. Zusätzlich zeigten die thermogravimetrischen Untersuchungen, dass ein dichteres Gefüge gleichzeitig durch den vermehrten Einbau von Kristallwasser gekennzeichnet war.

show abstract

Effects of elevated temperatures on the thermal behavior and mechanical performance of fly ash geopolymer paste, mortar and lightweight concrete

Cited by 297 publications

References 25 publications

Flexural Behaviour of Combined FA/GGBFS Geopolymer Concrete Beams after Exposure to Elevated Temperatures

Flexural Behaviour of Combined FA/GGBFS Geopolymer Concrete Beams after Exposure to Elevated Temperatures

Mechanical Properties of Geopolymer Concrete Exposed to Combustion

Einfluss der Kristallinität auf die Festigkeit und die Mikrostruktur alkalisch aktivierter Metakaoline

Contact Info

Product

Resources

About