Publication detail

Study of synergistic effect of fly ash and superabsorbent polymers on properties of cement pastes

MELICHAR, J. ČERNÝ, V. MÉSZÁROSOVÁ, L. DROCHYTKA, R. DUFKA, A. FIGALA, P. BARÁNEK, Š.

Original Title

Study of synergistic effect of fly ash and superabsorbent polymers on properties of cement pastes

Type

journal article in Web of Science

Language

English

Original Abstract

The main goal of this study is to observe changes in microstructural properties and the mutual interaction of cement pastes containing superabsorbent polymers (SAPs) and fly ash. SAP is a type of hydrogel additive, able to absorb large amounts of liquid in its structure. In cement-based materials, it is often used in the early stages of matrix hydration to absorb excess mixing water and to release it in the later stages, which is even more desirable when the material is exposed to higher temperatures. Another research goal is a partial substitution of binder (Portland cement) by the energy by-product of high-temperature ash, produced by the combustion of brown coal. A further goal is the observation of the interactions of these binders with the SAPs on the microstructural scale. For this purpose, computed tomography (CT), X-ray diffraction (XRD), differential thermal analysis (DTA), and scanning electron microscopy (SEM) were performed. Basic physical and mechanical properties such as compressive strength, flexural strength, and bulk density were also determined. In the early stages of hydration, viscosity and chemical shrinkage were determined. From the results obtained, it is obvious that the presence of SAPs has a significant impact on the properties of cement pastes. From the two tested SAPs, SAP HM has a positive effect on volume stability and the flexural strength of the composite. The results of the mineralogical composition showed that the effect of SAP incorporation influences the crystallization of portlandite, alite, belite, and calcite. SEM analysis confirmed the results of XRD analysis and proved that hydration products can grow into SAP cavities. It is clear from the evaluation of the pore structure that SAPs increase the porosity of cement composites. The admixture of high-temperature fly ash has a positive effect on reducing the volumetric changes of mixtures. The mechanical parameters of the composite with fly ash were similar to that of the reference test specimens.

Keywords

Superabsorbent polymers; Cement pastes; Fly ash; Study of microstructure

Authors

MELICHAR, J.; ČERNÝ, V.; MÉSZÁROSOVÁ, L.; DROCHYTKA, R.; DUFKA, A.; FIGALA, P.; BARÁNEK, Š.

Released

17. 10. 2023

Publisher

Elsevier

Location

AMSTERDAM, NETHERLANDS

ISBN

2352-7102

Periodical

Journal of Building Engineering

Year of study

79

Number

107897

State

Kingdom of the Netherlands

Pages from

1

Pages to

20

Pages count

20

URL

https://authors.elsevier.com/c/1hxKs8MyS96aBe

BibTex

@article{BUT184930,
  author="Jindřich {Melichar} and Vít {Černý} and Lenka {Mészárosová} and Rostislav {Drochytka} and Amos {Dufka} and Petr {Figala} and Šimon {Baránek}",
  title="Study of synergistic effect of fly ash and superabsorbent polymers on properties of cement pastes",
  journal="Journal of Building Engineering",
  year="2023",
  volume="79",
  number="107897",
  pages="20",
  doi="10.1016/j.jobe.2023.107897",
  issn="2352-7102",
  url="https://authors.elsevier.com/c/1hxKs8MyS96aBe"
}