Publication detail

Resistance of Lime-Natural Pozzolan Mortars in Salt-Laden Environments

VYŠVAŘIL, M. BAYER, P. DVOŘÁK, K.

Original Title

Resistance of Lime-Natural Pozzolan Mortars in Salt-Laden Environments

Type

conference paper

Language

English

Original Abstract

Salt crystallization belongs to the main decay processes in historic masonry mortars in which lime-pozzolan binders were often used. In this paper, the resistance to salts crystallization, their accumulation, and the microstructural changes of lime mortars with five different natural pozzolans are thoroughly investigated. Natural, fine ground, thermally untreated pozzolans (chalcedonite, pumice, zeolite, spongilite, and lava) were used as a partial replacement for lime in the amount of 10%, 20%, and 40%. The salt crystallization resistance of mortars were determined using Na2SO4, NaCl, and NH4NO3 solutions. The microstructure of the mortars after the testing was monitored with a scanning electron microscope, the accumulation of anions in the mortars was determined by chemical analyses and mass increases, and the formation of new minerals was confirmed using X-ray diffraction analysis. Nitrates were most accumulated in mortars with lava, sulfates in spongilite mortars, and chlorides in mortars with chalcedonite. Both crystalline and amorphous neoplasms were observed in the microstructures of mortars, the most common being nitrocalcite, cesanite, gypsum, ettringite, and hydrocalumite. The results showed that different natural pozzolans are a bit more suited to different saline environments and it should be considered when using them.

Keywords

Lime Mortar; Natural Pozzolan; Salt Crystallization; Salt accumulation; Microstructural Changes

Authors

VYŠVAŘIL, M.; BAYER, P.; DVOŘÁK, K.

Released

10. 6. 2023

Publisher

Springer Cham

ISBN

978-3-031-33211-1

Book

International RILEM Conference on Synergising Expertise towards Sustainability and Robustness of Cement-based Materials and Concrete Structures, SynerCrete’23

ISBN

2211-0844

Periodical

RILEM Bookseries

Year of study

1

Number

43

State

Federal Republic of Germany

Pages from

697

Pages to

706

Pages count

10

BibTex

@inproceedings{BUT184552,
  author="Martin {Vyšvařil} and Patrik {Bayer} and Karel {Dvořák}",
  title="Resistance of Lime-Natural Pozzolan Mortars in Salt-Laden Environments",
  booktitle="International RILEM Conference on Synergising Expertise towards Sustainability and Robustness of Cement-based Materials and Concrete Structures, SynerCrete’23",
  year="2023",
  journal="RILEM Bookseries",
  volume="1",
  number="43",
  pages="697--706",
  publisher="Springer Cham",
  doi="10.1007/978-3-031-33211-1\{_}63",
  isbn="978-3-031-33211-1",
  issn="2211-0844"
}