Comparison of lithomarge and cement-based mortars performance in aggressive aqueous environments

Jacek Kwasny, Timothy Aiken, Marios Soutsos, David Cleland, Andrew McIntosh

Research output: Contribution to conferencePaper

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Abstract

The resistance of room temperature cured geopolymer mortar (GPM) against chemical attacks, i.e. sodium and magnesium sulfate solutions, and sulfuric and hydrochloric acid solutions, was evaluated. GPM was formulated using a lithomarge precursor (low-purity kaolin) to achieve 28-day characteristic compressive strength of 60 MPa. Its performance was compared with an equivalent Portland cement mortar (PCM) having the same paste volume and strength grade. 28-day old bar samples were stored in 0.352 mol/L sulfate solutions for 52 weeks whereas 28-day old cube samples were exposed for 8 weeks to acid solutions with concentration of 0.52 mol/L. GPM showed superior performance against sulfate attack when compared to PCM. No visual deterioration was observed in GPM, the length changes were relatively small, and no changes to the microstructure were detected – in contrast to severely deteriorated PCM. As confirmed by visual observations and lower mass loss, GPM showed better resistance to attack by both acids than PCM. GPM provided a better quality (lower permeability) of an acid-degraded layer, lowering the degree of further deterioration. The main mechanisms of the matrix deterioration of GPM in both acids was dealumination of the hardened binder, with a higher degree of changes detected for sulfuric acid.
Original languageEnglish
Number of pages10
Publication statusPublished - 2018
EventSixth International Conference on the Durability of Concrete Structures - University of Leeds , Leeds, United Kingdom
Duration: 18 Jul 201820 Jul 2018
https://engineering.leeds.ac.uk/info/201479/conferences/270/sixth_international_conference_on_durability_of_concrete_structures_icdcs2018

Conference

ConferenceSixth International Conference on the Durability of Concrete Structures
Abbreviated titleICDCS2018
CountryUnited Kingdom
CityLeeds
Period18/07/201820/07/2018
Internet address

Fingerprint

cement
acids
deterioration
sulfuric acid
sulfates
water
magnesium sulfate
sodium sulfate
kaolin
hydrochloric acid
purity
microstructure
ambient temperature
permeability
sampling

Keywords

  • Lithomarge
  • Geopolymer mortars
  • Portland cement mortars
  • Sulfate attack
  • Acid attack

Cite this

Kwasny, J., Aiken, T., Soutsos, M., Cleland, D., & McIntosh, A. (2018). Comparison of lithomarge and cement-based mortars performance in aggressive aqueous environments. Paper presented at Sixth International Conference on the Durability of Concrete Structures, Leeds, United Kingdom.
Kwasny, Jacek ; Aiken, Timothy ; Soutsos, Marios ; Cleland, David ; McIntosh, Andrew. / Comparison of lithomarge and cement-based mortars performance in aggressive aqueous environments. Paper presented at Sixth International Conference on the Durability of Concrete Structures, Leeds, United Kingdom.10 p.
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abstract = "The resistance of room temperature cured geopolymer mortar (GPM) against chemical attacks, i.e. sodium and magnesium sulfate solutions, and sulfuric and hydrochloric acid solutions, was evaluated. GPM was formulated using a lithomarge precursor (low-purity kaolin) to achieve 28-day characteristic compressive strength of 60 MPa. Its performance was compared with an equivalent Portland cement mortar (PCM) having the same paste volume and strength grade. 28-day old bar samples were stored in 0.352 mol/L sulfate solutions for 52 weeks whereas 28-day old cube samples were exposed for 8 weeks to acid solutions with concentration of 0.52 mol/L. GPM showed superior performance against sulfate attack when compared to PCM. No visual deterioration was observed in GPM, the length changes were relatively small, and no changes to the microstructure were detected – in contrast to severely deteriorated PCM. As confirmed by visual observations and lower mass loss, GPM showed better resistance to attack by both acids than PCM. GPM provided a better quality (lower permeability) of an acid-degraded layer, lowering the degree of further deterioration. The main mechanisms of the matrix deterioration of GPM in both acids was dealumination of the hardened binder, with a higher degree of changes detected for sulfuric acid.",
keywords = "Lithomarge, Geopolymer mortars, Portland cement mortars, Sulfate attack, Acid attack",
author = "Jacek Kwasny and Timothy Aiken and Marios Soutsos and David Cleland and Andrew McIntosh",
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Kwasny, J, Aiken, T, Soutsos, M, Cleland, D & McIntosh, A 2018, 'Comparison of lithomarge and cement-based mortars performance in aggressive aqueous environments', Paper presented at Sixth International Conference on the Durability of Concrete Structures, Leeds, United Kingdom, 18/07/2018 - 20/07/2018.

Comparison of lithomarge and cement-based mortars performance in aggressive aqueous environments. / Kwasny, Jacek; Aiken, Timothy; Soutsos, Marios; Cleland, David; McIntosh, Andrew.

2018. Paper presented at Sixth International Conference on the Durability of Concrete Structures, Leeds, United Kingdom.

Research output: Contribution to conferencePaper

TY - CONF

T1 - Comparison of lithomarge and cement-based mortars performance in aggressive aqueous environments

AU - Kwasny, Jacek

AU - Aiken, Timothy

AU - Soutsos, Marios

AU - Cleland, David

AU - McIntosh, Andrew

PY - 2018

Y1 - 2018

N2 - The resistance of room temperature cured geopolymer mortar (GPM) against chemical attacks, i.e. sodium and magnesium sulfate solutions, and sulfuric and hydrochloric acid solutions, was evaluated. GPM was formulated using a lithomarge precursor (low-purity kaolin) to achieve 28-day characteristic compressive strength of 60 MPa. Its performance was compared with an equivalent Portland cement mortar (PCM) having the same paste volume and strength grade. 28-day old bar samples were stored in 0.352 mol/L sulfate solutions for 52 weeks whereas 28-day old cube samples were exposed for 8 weeks to acid solutions with concentration of 0.52 mol/L. GPM showed superior performance against sulfate attack when compared to PCM. No visual deterioration was observed in GPM, the length changes were relatively small, and no changes to the microstructure were detected – in contrast to severely deteriorated PCM. As confirmed by visual observations and lower mass loss, GPM showed better resistance to attack by both acids than PCM. GPM provided a better quality (lower permeability) of an acid-degraded layer, lowering the degree of further deterioration. The main mechanisms of the matrix deterioration of GPM in both acids was dealumination of the hardened binder, with a higher degree of changes detected for sulfuric acid.

AB - The resistance of room temperature cured geopolymer mortar (GPM) against chemical attacks, i.e. sodium and magnesium sulfate solutions, and sulfuric and hydrochloric acid solutions, was evaluated. GPM was formulated using a lithomarge precursor (low-purity kaolin) to achieve 28-day characteristic compressive strength of 60 MPa. Its performance was compared with an equivalent Portland cement mortar (PCM) having the same paste volume and strength grade. 28-day old bar samples were stored in 0.352 mol/L sulfate solutions for 52 weeks whereas 28-day old cube samples were exposed for 8 weeks to acid solutions with concentration of 0.52 mol/L. GPM showed superior performance against sulfate attack when compared to PCM. No visual deterioration was observed in GPM, the length changes were relatively small, and no changes to the microstructure were detected – in contrast to severely deteriorated PCM. As confirmed by visual observations and lower mass loss, GPM showed better resistance to attack by both acids than PCM. GPM provided a better quality (lower permeability) of an acid-degraded layer, lowering the degree of further deterioration. The main mechanisms of the matrix deterioration of GPM in both acids was dealumination of the hardened binder, with a higher degree of changes detected for sulfuric acid.

KW - Lithomarge

KW - Geopolymer mortars

KW - Portland cement mortars

KW - Sulfate attack

KW - Acid attack

M3 - Paper

ER -

Kwasny J, Aiken T, Soutsos M, Cleland D, McIntosh A. Comparison of lithomarge and cement-based mortars performance in aggressive aqueous environments. 2018. Paper presented at Sixth International Conference on the Durability of Concrete Structures, Leeds, United Kingdom.